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  • 1.
    Andersson, Sofia
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Biobaserade material.
    Bengtsson, Andreas
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi. KTH Royal institute of technology, Sweden.
    Åkerström, Mårten
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Sedin, Maria
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Sjöholm, Elisabeth
    RISE - Research Institutes of Sweden, Bioekonomi, Biobaserade material.
    The impact of inorganic elements on lignin‐based carbon fibre quality2018Ingår i: 15th European workshop on lignocelllulosics and pulp: Proceedings for poster presentations, 2018, s. 119-122Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    The influence of inorganic elements on lignin ‐based carbon fibre (CF) quality was studied using sulphates of Na +, K+, Mg2+, Fe2+, Al3+. The metal sulphates were added to wet spun prefibres made from softwood kraft lignin (SKL):cellulose (70:30) and melt spun prefibres made from low molecular mass SKL. An increase in concentration from 0.1 w% to about 0.4 w% did neither affect the mechanical properties nor the morphology as observed by SEM. In contrast, metal sulphates added to the initial 0.45 w% to a total range 1.5 to 5.0 w%, was found detrimental to the melt spinning and to the final CF quality. Thus, the recommendation of <0.1 w% ash in kraft lignin may be exceeded, but more research is needed to establish the upper concentration limit.

  • 2.
    Ankerfors, Caroline
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Gimåker, Magnus
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Östlund, Ida
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Polyelectrolyte Multilayers and Other Dosage Strategies: Effects on Properties of Paper Sheets Produced in Pilot Scale Using MillProcess Waters2018Ingår i: Paper Conference and Trade Show, PaperCon 2018: Shaping the future through innovation, TAPPI , 2018, Vol. 2, s. 658-669, artikel-id PA3.3Konferensbidrag (Övrigt vetenskapligt)
  • 3.
    Baison, John
    et al.
    SLU Swedish University of Agricultural Science, Sweden.
    Vidalis, Amaryllis
    Technische Universität München, Germany.
    Zhou, Linghua
    SLU Swedish University of Agricultural Science, Sweden.
    Chen, Zhi-Qiang
    SLU Swedish University of Agricultural Science, Sweden.
    Li, Zitong
    University of Helsinki, Finland.
    Sillanpää, Mikko J
    University of Oulu, Finland.
    Bernhardsson, Carolina
    SLU Swedish University of Agricultural Science, Sweden.
    Scofield, Douglas
    Uppsala University, Sweden.
    Forsberg, Nils
    SLU Swedish University of Agricultural Science, Sweden.
    Grahn, Thomas
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Olsson, Lars
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Karlsson, Bo
    Skogforsk, Sweden.
    Wu, Harry
    SLU Swedish University of Agricultural Science, Sweden.
    Ingvarsson, Pär K
    Umeå University, Sweden.
    Lundqvist, Sven-Olof
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar. IIC, Sweden.
    Niittylä, Totte
    SLU Swedish University of Agricultural Science, Sweden.
    Garcia-Gil, M Rosario
    SLU Swedish University of Agricultural Science, Sweden.
    Genome-Wide Association Study (GWAS) identified novel candidate loci affecting wood formation in Norway spruce2019Ingår i: The Plant Journal, ISSN 0960-7412, E-ISSN 1365-313X, Vol. 100, nr 1, s. 83-100Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Norway spruce is a boreal forest tree species of significant ecological and economic importance. Hence there is a strong imperative to dissect the genetics underlying important wood quality traits in the species. We performed a functional Genome-Wide Association Study (GWAS) of 17 wood traits in Norway spruce using 178101 single-nucleotide polymorphisms (SNPs) generated from exome genotyping of 517 mother trees. The wood traits were defined using functional modelling of wood properties across annual growth rings.We applied a LASSO based association mapping method using a functional multi-locus mapping approach that utilizes latent traits, with a stability selection probability method as the hypothesis testing approach to determine significant Quantitative Trait Loci (QTLs). The analysis provided 52 significant SNPs from 39 candidate genes, including genes previously implicated in wood formation and tree growth in spruce and other species. Our study represents a multi-locus GWAS for complex wood traits in Norway spruce. The results advance our understanding of the genetics influencing wood traits and identifies candidate genes for future functional studies.

  • 4.
    Baker, Darren
    et al.
    Baker Consulting, USA.
    Hosseinaei, Omid
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Sedin, Maria
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Echardt, Linda
    Södra skogsägarna ekonomisk förening, Sweden.
    Capanema, Ewellyn
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Lignin-based carbon fiber: effect of softwood kraft lignin separation method on multifilament melt-spinning performance and conversion2019Ingår i: 20th International symposium on wood, fiber, and pulping chemistry, 2019Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    A reference lignin separated from an industrial softwood kraft black liquor via an improved LignoBoost process was compared to four other lignins derived from the same liquor. The four lignins were produced by using a) pH-fractionation within the LignoBoost process, b) ultrafiltration of black liquor prior to the LignoBoost process, and c) solvent leaching of the reference lignin using methanol and d) ethanol.Lignin compositional characteristics and thermal properties were compared, and monofilament extrusion used to assess their potential for successful melt spinning at the 24 filament scale. The lignin prepared by ethanol leaching of the reference lignin was found to be most appropriate for potential pilot scale fibre production. This was owing to a high purity, lower comparative glass transition temperature (Tg), and good spinning performance.Thermal pretreatments of the ethanol leached lignin gave a selection of enhanced lignins which were characterized for comparison, and melt spun on pilot multifilament equipment. The enhanced lignins could be continuously melt spun giving filaments with diameters as low as 10 μm and with minimal defects. Conversion of selected filaments provided carbon fibres with a tensile strength of 1259 ± 159 MPa, tensile modulus of 67 ± 3 GPa and diameter of 7.3 ± 0.5 μm.

  • 5.
    Barbero-López, Aitor
    et al.
    University of Eastern Finland, Finland.
    Chibily, Soumay
    University of Eastern Finland, Finland.
    Scheepers, Gerhard
    RISE - Research Institutes of Sweden, Bioekonomi, Biobaserade material.
    Grahn, Thomas
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Venäläinen, Martti
    Natural Resources Institute Finland, Finland.
    Haapala, Antti
    University of Eastern Finland, Finland.
    Analysis of Green Wood Preservation Chemicals2018Ingår i: World Academy of Science, Engineering and Technology: An International Journal of Science, Engineering and Technology, ISSN 2010-376X, E-ISSN 2070-3740, Vol. 12, nr 3, s. 175-181Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Wood decay is addressed continuously within thewood industry through use and development of wood preservatives.The increasing awareness on the negative effects of many chemicalstowards the environment is causing political restrictions in their useand creating more urgent need for research on green alternatives.This paper discusses some of the possible natural extracts for woodpreserving applications and compares the analytical methodsavailable for testing their behavior and efficiency against decayfungi. The results indicate that natural extracts have interestingchemical constituents that delay fungal growth but vary in efficiencydepending on the chemical concentration and substrate used. Resultsalso suggest that presence and redistribution of preservatives in woodduring exposure trials can be assessed by spectral imaging methodsalthough standardized methods are not available. This studyconcludes that, in addition to the many standard methods available,there is a need to develop new faster methods for screening potentialpreservative formulation while maintaining the comparability andrelevance of results.

  • 6.
    Bengtsson, Andreas
    et al.
    KTH Royal Institute of Technology, Sweden.
    Bengtsson, Jenny
    RISE - Research Institutes of Sweden, Material och produktion, IVF.
    Olsson, Carina
    RISE - Research Institutes of Sweden, Material och produktion, IVF.
    Sedin, Maria
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Jedvert, Kerstin
    RISE - Research Institutes of Sweden, Material och produktion, IVF.
    Theliander, Hans
    Chalmers University of Technology, Sweden.
    Sjöholm, Elisabeth
    RISE - Research Institutes of Sweden, Bioekonomi, Biobaserade material.
    Improved yield of carbon fibres from cellulose and kraft lignin2018Ingår i: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 72, nr 12, s. 1007-1016Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    To meet the demand for carbon-fibre-reinforced composites in lightweight applications, cost-efficient processing and new raw materials are sought for. Cellulose and kraft lignin are each interesting renewables for this purpose due to their high availability. The molecular order of cellulose is an excellent property, as is the high carbon content of lignin. By co-processing cellulose and lignin, the advantages of these macromolecules are synergistic for producing carbon fibre (CF) of commercial grade in high yields. CFs were prepared from precursor fibres (PFs) made from 70:30 blends of softwood kraft lignin (SW-KL) and cellulose by dry-jet wet spinning with the ionic liquid (IL) 1-ethyl-3-methylimidazolium acetate ([EMIm][OAc]) as a solvent. In focus was the impact of the molecular mass of lignin and the type of cellulose source on the CF yield and properties, while membrane-filtrated kraft lignin and cellulose from dissolving kraft pulp and fully bleached paper-grade SW-KP (kraft pulp) served as sources. Under the investigated conditions, the yield increased from around 22% for CF from neat cellulose to about 40% in the presence of lignin, irrespective of the type of SW-KL. The yield increment was also higher relative to the theoretical one for CF made from blends (69%) compared to those made from neat celluloses (48-51%). No difference in the mechanical properties of the produced CF was observed.

  • 7.
    Bengtsson, Andreas
    et al.
    KTH Royal Institute of Technology, Sweden.
    Bengtsson, Jenny
    RISE - Research Institutes of Sweden, Material och produktion, IVF.
    Sedin, Maria
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Sjöholm, Elisabeth
    RISE - Research Institutes of Sweden, Bioekonomi, Biobaserade material.
    Carbon Fibers from Lignin-Cellulose Precursors: Effect of Stabilization Conditions2019Ingår i: ACS Sustainable Chemistry and Engineering, ISSN 2168-0485, Vol. 7, nr 9, s. 8440-8448Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    There is an increasing demand for lightweight composites reinforced with carbon fibers (CFs). Due to its high availability and carbon content, kraft lignin has gained attention as a potential low-cost CF precursor. CFs with promising properties can be made from flexible dry-jet wet spun precursor fibers (PFs) from blends (70:30) of softwood kraft lignin and fully bleached softwood kraft pulp. This study focused on reducing the stabilization time, which is critical in CF manufacturing. The impact of stabilization conditions on chemical structure, yield, and mechanical properties was investigated. It was possible to reduce the oxidative stabilization time of the PFs from about 16 h to less than 2 h, or even omitting the stabilization step, without fusion of fibers. The main reactions involved in the stabilization stage were dehydration and oxidation. The results suggest that the isothermal stabilization at 250 °C override the importance of having a slow heating rate. For CFs with a commercial diameter, stabilization of less than 2 h rendered in tensile modulus 76 GPa and tensile strength 1070 MPa. Impregnation with ammonium dihydrogen phosphate significantly increased the CF yield, from 31-38 to 46-50 wt %, but at the expense of the mechanical properties.

  • 8.
    Björk, Elisabeth
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Bouveng, Mikael
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Holmqvist, Claes
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Vomhoff, Hannes
    Holmen AB, Sweden.
    Fibre-based strength aids for increased board stiffness2019Ingår i: PaperCon 2019: proceedings, TAPPI Press, 2019, artikel-id PF2.3Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    A pilot scale study has been made of the concept of adding fibre-based strength agents (fines enriched (FE)-pulp or highly refined (HR)-pulp) in a board middle ply containing chemithermomechanical bleached pulp (CTMP) in order to increase bending stiffness of the board while maintaining Z-strength. It has been demonstrated that the bending stiffness of a sheet consisting of a top ply and a CTMP based middle ply could be improved by increasing the CTMP fraction and preventing Z-strength loss via addition of a fibre based strength agent. Compared with the reference pulp, both Z-strength and bulk increased for three of the compositions, namely 65% CTMP with 5% strength agent of either FE or HR type and 85% CTMP with 10% HR-pulp. FE-pulp was found to be more efficient than HR-pulp concerning bending stiffness improvement. While the highly-refined fibres of the strength agents had a negative effect on the drainage resistance and press dryness, an increased share of CTMP increased the press dryness linearly. FE-pulp and HR-pulp had the same impact on press dryness. Press solids could be improved by approximately 2% without significantly reducing the bulk by increasing press loads.

  • 9.
    Björk, Elisabeth
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Bouveng, Mikael
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Vomhoff, Hannes
    Holmen AB, Sweden.
    Fines-enriched pulp as a strength agent in a CTMP middle ply2018Ingår i: PaperCon 2018: Shaping the future through innovation, TAPPI , 2018, s. 741-760, artikel-id PA5.2Konferensbidrag (Refereegranskat)
    Abstract [en]

    The objective of this pilot scale trial, was to evaluate fines-enriched pulp (FE-pulp) as a strength agent in amiddle ply of a board product.A typical CTMP-based middle ply was produced on the FEX pilot paper machine. The stock consisted of CTMP,refined hardwood and softwood pulp, and filler. FE-pulp as strength agent was compared with glue pulp, ahighly refined chemical pulp. FEX sheets and hand sheets made of pulp mixtures were evaluated. Also, thedewatering and pressing conditions on the paper machine were compared.The results confirmed the results of earlier experiments with handsheets; FE-pulp used as strength agent showedto be twice as efficient as glue pulp regarding strength properties without impairing the bulk. Further, thedewatering conditions and press dryness's on the paper machine was comparable at these additions. Thus, allthese results imply that addition of FE-pulp can replace the double amount of glue pulp as a strength agent.

  • 10.
    Björk, Elisabeth
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Bouveng, Mikael
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Vomhoff, Hannes
    Holmen AB, Sweden.
    Production of pulps with an extremely high fines content for use as strength agent2018Ingår i: PaperCon 2018: Shaping the future through innovation, TAPPI , 2018, artikel-id PA5.1Konferensbidrag (Refereegranskat)
    Abstract [en]

    The objective was to optimize the production of fines-enriched pulp (FE-pulp) from chemical pulp.The first trial was a continuous production of FE-pulp with unbleached and bleached never-dried softwood. Thepulp was refined using a JC00 equipped with SF filling, and screened with a micro-perforated screen basket with250 μm diameter holes, but the produced FE-pulp got low concentration, below 3 g/l.The second trial aimed at optimised conditions, using dried bleached softwood. Three fillings, microbar, AA andFF were evaluated in a JC01 refiner, where microbar was most energy efficient. Microbar and AA reachedtargeted FE-pulp concentration, 10 g/l. The refined pulps were screened with different hole diameters, where, asexpected, larger hole diameters resulted in higher concentration but also lower fines content in the FE-pulps.The last trial, the microbar filling was evaluated for never-dried softwood pulp, unbleached and bleached. Now,the refining of unbleached softwood gave 3 times more fines per kWh/ton compared with first trial.These trials demonstrated the importance of the right refining conditions regarding effect of refiner and type offilling to achieve glue-pulp with high enough fines content. With the right conditions, it was possible to produceFE-pulp with high concentration at moderate energy consumption.

  • 11.
    de san Pio, Ignacio
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Johansson, Klas G
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Krochak, Paul
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Filler co-flocculation with MFC: Novel predictive method2019Ingår i: PaperCon 2019: Proceedings, TAPPI Press, 2019, artikel-id PA2-PF1.2Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Research has been undertaken in which a combination of different techniques was utilised to compare pre-flocculation (flocculant added to the filler prior to its addition to the pulp) with pre-mixing strategies, also called co-flocculation (chemicals added to a mixture of cellulose microfibrils (CMF) and filler. The pulp used was a mixture of 80% hardwood kraft pulp and 20% softwood kraft pulp. The filler was ground calcium carbonate (GCC), while the chemicals used included cationic polyacrylamide (CPAM), silica, bentonite, anionic PAM (APAM), cationic starch and CMF. Using the focused beam reflectance method (FBRM) enabled an in-depth and quick study of the filler floc behaviour at different dosages and mixing conditions, demonstrating that it was a very good tool as a pre-screening for different treatment alternatives. Clear differences in behaviour between different pre-flocculation and pre-mixing strategies were observed. For the pre-mixing strategy, the most promising results were achieved with CPAM plus bentonite and cationic starch systems. Although dewatering was negatively affected with pre-mixing, the mechanical properties were clearly improved. Flocs obtained with PCAM/bentonite had a similar resistance with both strategies, while cationic starch was clearly more advantageous when using the pre-mixing strategy.

  • 12.
    Edberg, Jesper
    et al.
    RISE - Research Institutes of Sweden, ICT, Acreo. Linköping University, Sweden.
    Brooke, Robert
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Granberg, Hjalmar
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Engquist, Isak
    Linköping University, Sweden; Wallenberg Wood Science Center, Sweden.
    Berggren, Magnus
    Linköping University, Sweden; Wallenberg Wood Science Center, Sweden.
    Improving the Performance of Paper Supercapacitors Using Redox Molecules from Plants2019Ingår i: Advanced Sustainable Systems, Vol. 3, nr 8, artikel-id 1900050Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A supercapacitor made from organic and nature‐based materials, such as conductive polymers (PEDOT:PSS), nanocellulose, and an the organic dye molecule (alizarin), is demonstrated. The dye molecule, which historically was extracted from the roots of the plant rubia tinctorum, is here responsible for the improvement in energy storage capacity, while the conductive polymer provides bulk charge transport within the composite electrode. The forest‐based nanocellulose component provides a mechanically strong and nonporous network onto which the conductive polymer self‐organizes. The electrical and electrochemical properties of the material composition are investigated and prototype redox‐enhanced supercapacitor devices with excellent specific capacitance exceeding 400 F g−1 and an operational stability over >1000 cycles are demonstrated. This new class of supercapacitors, which in part are based on organic materials from plants, represents an important step toward a green and sustainable energy technology.

  • 13.
    Edlund, Ulrica
    et al.
    KTH Royal Institute of Technology, Sweden.
    Lagerberg, Tove
    Ålander, Eva
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Admicellar Polymerization Coating of CNF Enhances Integration in Degradable Nanocomposites2019Ingår i: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 20, nr 2, s. 684-692Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A water-based one-pot synthesis strategy for converting cellulose nanofibrils (CNF) into a hydrophobic and processable biopolymer grade is devised. CNF was chemically modified through admicellar polymerization, producing fibrils coated with fatty acrylate polymers. The proposed modification targets a change in the interfibrillar interactions and improved CNF compatibility with a degradable plastic composite matrix, poly(butylene adipate-co-terephthalate), PBAT in composites prepared by melt extrusion. CNF had a clear reinforcing effect on PBAT, increasing Young's modulus by at least 35% and 169% at 5 and 20% (w/w) CNF content, respectively. However, unmodified CNF showed aggregation, poor adhesion in the matrix, and severely impaired the ductility of PBAT. CNF modified by admicellar polymerization was homogeneously dispersed in the PBT matrix and showed significantly better preservation of the elongation properties compared to unmodified CNF, especially at 5% (w/w) addition level.

  • 14.
    Erlandsson, Johan
    et al.
    KTH Royal Institute of Technology, Sweden.
    Françon, Hugo
    KTH Royal Institute of Technology, Sweden.
    Marais, Andrew
    KTH Royal Institute of Technology, Sweden.
    Granberg, Hjalmar
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Wågberg, Lars
    KTH Royal Institute of Technology, Sweden.
    Cross-Linked and Shapeable Porous 3D Substrates from Freeze-Linked Cellulose Nanofibrils.2019Ingår i: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 20, nr 2, s. 728-737Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Chemically cross-linked highly porous nanocellulose aerogels with complex shapes have been prepared using a freeze-linking procedure that avoids common post activation of cross-linking reactions and freeze-drying. The aerogel shapes ranged from simple geometrical three-dimensional bodies to swirls and solenoids. This was achieved by molding or extruding a periodate oxidized cellulose nanofibril (CNF) dispersion prior to chemical cross-linking in a regular freezer or by reshaping an already prepared aerogel by plasticizing the structure in water followed by reshaping and locking the aerogel into its new shape. The new shapes were most likely retained by new cross-links formed between CNFs brought into contact by the deformation during reshaping. This self-healing ability to form new bonds after plasticization and redrying also contributed to the mechanical resilience of the aerogels, allowing them to be cyclically deformed in the dry state, reswollen with water, and redried with good retention of mechanical integrity. Furthermore, by exploiting the shapeability and available inner structure of the aerogels, a solenoid-shaped aerogel with all surfaces coated with a thin film of conducting polypyrrole was able to produce a magnetic field inside the solenoid, demonstrating electromagnetic properties. Furthermore, by biomimicking the porous interior and stiff exterior of the beak of a toucan bird, a functionalized aerogel was created by applying a 300 μm thick stiff wax coating on its molded external surfaces. This composite material displayed a 10-times higher elastic modulus compared to that of the plain aerogel without drastically increasing the density. These examples show that it is possible to combine advanced shaping with functionalization of both the inner structure and the surface of the aerogels, radically extending the possible use of CNF aerogels.

  • 15.
    Granberg, Hjalmar
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Håkansson, Karl
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Fall, Andreas
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Wågberg, Pia
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Electroactive papers, films, filaments, aerogels and hydrogels to realize the future of bio-based electronics2019Ingår i: PaperCon 2019: Proceedings, TAPPI Press, 2019, artikel-id PF4.1Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Research has been undertaken into the mixing of electroactive additives (EAA), for example, conducting polymers or particles, in five different cellulose structures and their further processing into electroactive papers and films. The cellulose structures considered included cellulose nanofibrils (CNF) hydrogels, CNG aerogels, CNF filaments, CNF films and cellulose papers. It has been demonstrated that the cellulose structure in combination with the electroactive polymer or particle, could be used to tailor numerous different properties. The cellulose could provide properties that support structural integrity, processability, ionic conductivity, shapeability and a large inner capacitive surface. The highly porous aerogel particles could be shaped using three-dimensional printed templates prior to freezing. The particles could be filled either with active material from the start before freeze-linking or filled with active material afterwards based on the layer by layer method. Electroactive paper could also be produced by adding the active component directly as a filler during papermaking, by adding CNF spun EA filaments cut into conveniently long staple fibres.

  • 16.
    Granberg, Hjalmar
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Sandberg, Mats
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Håkansson, Karl
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Pilot scale production of interactive zinc oxide paper and its multiple applicability2019Ingår i: PaperCon 2019: Proceedings, TAPPI Press, 2019, artikel-id PF3.3Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    A study has been made of the production of zinc oxide (ZnO) paper in a pilot paper machine. Bleached sulphate softwood pulp (70%) and bleached sulphate hardwood pulp (30%) were corefined. Cationic polyacrylamide (CPAM) was used as retention agent, while alkyl ketene dimer (AKD) was used as sizing agent for some samples. Some papers were screen printed with a conducting carbon-based ink to produce a photosensor device. Two methods were used to study the photocatalysis: immersing ZnO papers into kongo red dispersions or resazurin (Rz) based photocatalyst activity indicator ink and exposing the papers to ultraviolet (UV) light in a sunlight simulator. ZnO papers of approximately 60gsm were successfully produced on the pilot scale machine, which was run at a low speed (100m/min) and the retention of ZnO particles was good in all samples. The paper looked like an ordinary white printing paper product, but was a truly interactive material, exhibiting photoconductivity and enabling use as an excellent photosensor.

  • 17.
    Hagman, Anton
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Evaluation of moulded pulp trays using compression test and novel twist test2019Ingår i: 29th IAPRI Symposium on packaging, 2019: Serving society innovative perspectives on packaging, 2019Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Within the industry there exists great experience of producing moulded pulp trays,this includes adjusting process parameters to achieve a consistent output from thetray making machines. However, the evaluation of the results is at this point based onhands on methods that ultimately relies on subjective opinions of what makes a goodtray. This includes visual inspection of the trays, as well as a twisting the trays by handto evaluate stiffness. Such methods might suffice to achieve a consistent output, butare not suited for structured development work, which requires objective measures.One obvious measurement is a compression test, like a box compression test. However, this test does not tell the whole story, and differs from the hands-on tests usedtoday. Because of this a twist test was developed to emulate the hands-on testingpresently used to assess the quality of moulded pulp trays. The test is performed in atensile tester, by putting the tray in a sample holder which supports two diagonal bottom corners while a beam is pressing against the opposite upper diagonal corners.This forces the tray to bend.Plotting the results from these two tests against each other, results in a practicalgraph that can be used to evaluate both pulp and process properties, as well as trayweights. This plot reveals that some information remains hidden if only compressiontests are performed.Finally, such a graph lends itself to define boundaries for what is an acceptable tray.

  • 18.
    Hagman, Anton
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Strength development during drying: possibilities with a different wet strength testing approach2019Ingår i: International Paper Physics Conference 2019, Indianapolis, IN, USA, 5-8 May 2019: preprint proceedings, TAPPI Press, 2019, s. 117-126Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    A new method has been proposed for mapping the tensile behaviour of paper during drying without the need for large amounts of material. Three pulps were used to make handsheets: a long fibre pulp (softwood) and a short fibre pulp (hardwood), as well as softwood pulp mixed with microfibrillated cellulose (MFC). Comparative testing was undertaken with rewetted commercial blotting papers. Strips were produced from never dried laboratory sheets using die cutting and tested using pneumatic clamps typically used for short span tensile tests. Using the span length of 30mm, four sample points could be sequentially measured on each strip, enabling faster testing while using less material. It was found that the strength levels were different, but that the general behaviour was very similar for all three pulps. In addition, the strength increase associated with the addition of MFC was found to be present during the whole drying process. It has been concluded that the proposed new method could enable the differences between short and long fibre pulps to be examined, as well as to characterise the effect of addition of MFC.

  • 19.
    Hagman, Anton
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Trost, Thomas
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Perforations on boxes: some fundamental facts2019Ingår i: 29th IAPRI Symposium on packaging, 2019: Serving society innovative perspectives on packaging, 2019Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    The grocery retail industry is striving with low margins and an ever-increasing competition from e-commerce applications. Therefore, as a mean to save time, money andincrease the efficiency in the supply chain, perforated shelf-ready packages (SRP) hassince a long time been used. However, there is also problems related to this perforation; it weakens the transport packaging and makes it more sensitive to damage onthe way to the shelf. The current guidelines are focused on appearance of the box onthe shelf, e.g. how much of the product is seen and evenness of perforate edge, andnot on the mechanical properties of the box.Today there exist much knowledge about perforations inhouse in the die cutting industry. This knowledge is however unattainable for outsiders. Further the questionarises about how well founded said knowledge is. The scientific literature offers littleinformation about the basics of perforation and how it affects the mechanical properties of the board and box. This study is an attempt to build knowledge, useful toconverters and industrial users, in a systematic way.In this paper several different perforations patterns have been studied from a mechanical point of view. The experiments were designed to answer some basic questionsabout how different nick lengths and distances affects the strength of the perforatione.g. at different cut/uncut ratios. Among methods studied were tensile testing, bending stiffness, compression testing and edge compression test. The different methodswere compared regarding sensitivity to discriminate between different perforationpatterns and give a useful classification of the perforation.

  • 20.
    Han, Shaobo
    et al.
    Linköping University, Sweden.
    Alvi, Naveed Ul Hassan
    Linköping University, Sweden.
    Granlöf, Lars
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Granberg, Hjalmar
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Berggren, Magnus
    Linköping University, Sweden.
    Fabiano, Simone
    Linköping University, Sweden.
    Crispin, Xavier
    Linköping University, Sweden.
    A Multiparameter Pressure–Temperature–Humidity Sensor Based on Mixed Ionic–Electronic Cellulose Aerogels2019Ingår i: Advanced Science, ISSN 2198-3844, artikel-id 1802128Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Pressure (P), temperature (T), and humidity (H) are physical key parameters of great relevance for various applications such as in distributed diagnostics, robotics, electronic skins, functional clothing, and many other Internet-of-Things (IoT) solutions. Previous studies on monitoring and recording these three parameters have focused on the integration of three individual single-parameter sensors into an electronic circuit, also comprising dedicated sense amplifiers, signal processing, and communication interfaces. To limit complexity in, e.g., multifunctional IoT systems, and thus reducing the manufacturing costs of such sensing/communication outposts, it is desirable to achieve one single-sensor device that simultaneously or consecutively measures P–T–H without cross-talks in the sensing functionality. Herein, a novel organic mixed ion–electron conducting aerogel is reported, which can sense P–T–H with minimal cross-talk between the measured parameters. The exclusive read-out of the three individual parameters is performed electronically in one single device configuration and is enabled by the use of a novel strategy that combines electronic and ionic Seebeck effect along with mixed ion–electron conduction in an elastic aerogel. The findings promise for multipurpose IoT technology with reduced complexity and production costs, features that are highly anticipated in distributed diagnostics, monitoring, safety, and security applications. © 2019 The Authors.

  • 21.
    Hansen, Peter H F
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Johansson, Klas
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Monitoring cross-thickness distributions of fines and CMF by dyeing and optical measurement2018Ingår i: PaperCon 2018: Shaping the future through innovation, TAPPI , 2018, artikel-id FF3Konferensbidrag (Refereegranskat)
    Abstract [en]

    A methodology has been verified where the ZD-distribution of a component of the furnish (fines or CMF) can bemonitored. The component to be monitored was dyed using a direct azo-dye before addition to the furnish. Theproduced sheets were sectioned in cross-thickness direction by sequential heat-seal lamination and splitting, usingplastic pouches. The amount of dyed material in a split was monitored using thea* and L* parameters of the CIELabcolor space and the opacity, all measured simultaneously with a spectrophotometer. The value on the green-redaxis,a*, the lightness, L, and the opacity were combined into a new parameter, -a*L/opac. Two mechanisms forfines retention was observed by laboratory studies, mechanical retention by filtering process in the formed fiber weband chemical retention by agglomeration to the fibers.The methodology has recently been applied for monitoring cross-thickness distributions of either CMF or fines inpaper produced in pilot scale trials. For example, it was demonstrated, that the machine settings affected themechanisms for retention of fines in the fiber web during sheet forming and dewatering, with different distributionsof fines in the cross-thickness direction as result.

  • 22.
    Holmqvist, Claes
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Rosén, Fredrik
    RISE - Research Institutes of Sweden, Bioekonomi.
    Söderberg, Daniel
    KTH Royal Institute of Technology, Sweden.
    In-Situ Measurements of Stock Flow Conditions in the Twin-Wire Forming Zone2018Ingår i: PaperCon 2018: Shaing the future through innovation, TAPPI , 2018, s. 59-72, artikel-id FF5.1Konferensbidrag (Refereegranskat)
    Abstract [en]

    In the present study, we report results from in-situ investigations of the forming process performed in the roll-bladesection of a pilot machine. Direct measurements of the drainage pressure along the forming zone were obtained usinga miniature fibre-optic pressure transducer inserted into the flow through the headbox jet. High-speed imaging oftracer particles using a transmitted light setup was performed to in an attempt to obtain direct measurements of thelocal stock speed. By replacing one section of a ceramic blade with a quartz glass piece, access was also obtained tothe region on top of the blade. The combined picture that emerges from these measurements is that the pressuredistribution and the velocity field along a twin-wire forming zone is significantly more complex than usuallyassumed, and that much remains to be understood about the dynamics of twin-wire forming.

  • 23.
    Javed, Asif
    et al.
    Karlstad University, Sweden.
    Rättö, Peter
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar. Karlstad University, Sweden.
    Järnström, Lars
    Karlstad University, Sweden.
    Ullsten, Henrik
    Karlstad University, Sweden.
    Crack analysis of barrier coatings based on starch and starch-PVOH with and without plasticizer2018Ingår i: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 33, nr 2, s. 336-347Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Barrier coatings based on starch and starch-PVOH plasticized with glycerol and without plasticizer were applied to two different paperboard substrates, a triple coated board and duplex board, in order to investigate the tendency for cracks to develop in the barrier coating layers during creasing and folding. Tensile properties of films based on the starch and starch-PVOH blend were determined to investigate the relationship between the flexibility of the films and the cracking in the barrier coating layers. Furthermore, the oxygen transmission rate through the barrier-coated paperboard was measured before and after creasing and folding. The oxygen transmission rate through the barrier-coated samples was over the measurable range i. e. OTR > 10000 cm 3 / m 2 day\text{OTR}>10000\hspace{0.1667em}{\text{cm}}^{3}/{\text{m}}^{2}\hspace{0.1667em}\text{day} after creasing and folding, which indicated failure in the barrier coating layers. Optical microscopy revealed small cracks in the barrier coating layers, probably related to an increase in flexibility of the barrier coating layers. It was observed in scanning electron micrographs that cracks in the barrier coating layers seemed to follow the fibers when the barrier coating was applied on the rear side of the duplex board. Scanning electron micrographs and surface profiler images revealed that cracks in the barrier coating layers might have originated from the mineral coating layer when the starch and starch/PVOH coating layers were applied on the mineral-coated side of the triple coated board. An increase in the thickness of the barrier coating layer did not seem to increase the resistance to failure.

  • 24.
    Javed, Asif
    et al.
    Karlstad University, Sweden.
    Ullsten, Henrik
    Karlstad University, Sweden.
    Rättö, Peter
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar. Karlstad University, Sweden.
    Järnström, Lars
    Karlstad University, Sweden.
    Lignin-containing coatings for packaging materials2018Ingår i: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 33, nr 3, s. 548-556Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The mechanical properties and chemical stability in water of self-supporting films made from aqueous solutions of starch and lignin, and the barrier properties of paperboard coated with solutions of these polymers have been studied. The dissolution of starch from the starch-lignin films in contact with the model liquids was decreased significantly when lignin was added to the starch films. The addition of ammonium zirconium carbonate (AZC) to the formulations as a crosslinking agent substantially increased the storage modulus of the starch-lignin films, which indicated that crosslinking had occurred. The addition of AZC to the formulations also led to a decrease in dissolution of both starch and lignin from the starch-lignin films in contact with model liquids. The effect of AZC on the water stability of the films was greater when the pH of the starch-lignin-AZC solution was adjusted with ammonia rather than NaOH. The addition of NH4Cl solution as a presumed catalyst to the recipe when the pH adjustment was performed with NaOH did not improve the effect of AZC on the water stability of the films. The water vapour transmission rate of the coated paperboard decreased slightly when AZC was added to the coating formulation.

  • 25.
    Karlsson, Rose-Marie Pernilla
    et al.
    KTH Royal Institute of Technology, Sweden.
    Larsson, Per Tomas
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi. KTH Royal Institute of Technology, Sweden.
    Yu, Shun
    KTH Royal Institute of Technology, Sweden.
    Pendergraph, Samuel
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Pettersson, Torbjörn
    KTH Royal Institute of Technology, Sweden.
    Hellwig, Johannes
    KTH Royal Institute of Technology, Sweden.
    Wågberg, Lars
    KTH Royal Institute of Technology, Sweden.
    Carbohydrate gel beads as model probes for quantifying non-ionic and ionic contributions behind the swelling of delignified plant fibers.2018Ingår i: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 519, s. 119-129, artikel-id S0021-9797(18)30200-5Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Macroscopic beads of water-based gels consisting of uncharged and partially charged β-(1,4)-d-glucan polymers were developed to be used as a novel model material for studying the water induced swelling of the delignified plant fiber walls. The gel beads were prepared by drop-wise precipitation of solutions of dissolving grade fibers carboxymethylated to different degrees. The internal structure was analyzed using Solid State Cross-Polarization Magic Angle Spinning Carbon-13 Nuclear Magnetic Resonance and Small Angle X-ray Scattering showing that the internal structure could be considered a homogeneous, non-crystalline and molecularly dispersed polymer network. When beads with different charge densities were equilibrated with aqueous solutions of different ionic strengths and/or pH, the change in water uptake followed the trends expected for weak polyelectrolyte gels and the trends found for cellulose-rich fibers. When dried and subsequently immersed in water the beads also showed an irreversible loss of swelling depending on the charge and type of counter-ion which is commonly also found for cellulose-rich fibers. Taken all these results together it is clear that the model cellulose-based beads constitute an excellent tool for studying the fundamentals of swelling of cellulose rich plant fibers, aiding in the elucidation of the different molecular and supramolecular contributions to the swelling.

  • 26.
    Knapic, Sofia
    et al.
    Universidade de Lisboa, Portugal.
    Grahn, Thomas
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Lundqvist, Sven-Olof
    RISE - Research Institutes of Sweden, Bioekonomi.
    Pereira, Helena
    Universidade de Lisboa, Portugal.
    Juvenile wood characterization of Eucalyptus botryoides and E. maculata by using SilviScan2018Ingår i: BioResources, ISSN 1930-2126, E-ISSN 1930-2126, Vol. 13, nr 2, s. 2342-2355Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The wood properties of 6-year-old Eucalyptus botryoides and Eucalyptus maculata point towards a possible aptitude for solid-wood end uses. Samples from E. botryoides and E. maculata were characterized regarding within-tree variation in wood density, radial and tangential fibre width, fibre wall thickness, fibre coarseness, microfibril angle, and stiffness based on SilviScan measurements taken radially from the pith outwards at varying stem height levels. The mean values of the studied wood properties for E. botryoides and E. maculata were, respectively: density 507 kg m-3 and 695 kg m-3, radial fibre width 17.4 Όm and 17.2 Όm, tangential fibre width 16.7 Όm and 16.9 Όm, fibre wall thickness 1.8 Όm and 2.5 Όm, fibre coarseness 161.2 Όgm-1 and 212.9 Όgm-1, microfibril angle 15.5° and 14.7°, and stiffness 9.6 GPa and 12.1 GPa. The variation in wood stiffness was explained to a large extent by microfibril angle and wood density variations. The results of the scans, along with the wood variability, indicated that both species should be considered for solid wood products or pulp production.

  • 27.
    Krochak, Paul
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Norman, Bo
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Practical Aspects of Retention Aids Addition on Web Structure Variability2018Ingår i: PaperCon 2018: Shaping the future throuch innovation, 2018, s. 6-15, artikel-id FF3.2Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this work, we report on a series of pilot scale production trials investigating the effect of addition location, dosage velocity ratio and dilution level of a single component retention system (CPAM) on filler retention, formation and in-plane web structure uniformity for a fine paper grade. Specifically, we considered addition levels (500 g/t and 1000 g/t), dosage velocity ratios (2 and 4.5), and pre-dilution (300x and 600x) and addition location (before and after the headbox pump). The in-plane distribution of fibre and filler material in the final product was then mapped in high resolution over 10m paper samples using moveable radiation emitters and detectors.It was shown that addition of CPAM before the headbox pump resulted in a reduction in filler retention and poor formation in the final product. The addition velocity ratio was shown to have only minor influence on retention, formation and web structure variability. However, low CPAM dilution levels resulted in a high degree of variability in the distribution of filler and fibre including streakiness. Moreover, at low dilution levels, the in-plane distribution of filler was highly correlated to that of the fibres. By optimizing the dilution level and addition location, conditions could be established to reduce CPAM addition levels without adversely affecting retention or product variability.

  • 28.
    Krochak, Paul
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Östlund, Catherine
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Tysen, Aron
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    The effect of felt-web structure interaction on press dryness variability2019Ingår i: International Paper Physics Conference 2019 : preprint proceedings: PaperCon 2019, TAPPI Press, 2019, s. 175-180Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Laboratory trials were carried out in order to clarify the interaction between felt and web structure and its impact on dryness variability. Oriented laboratory sheets of 80gsm and consisting of 100% never dried unbleached softwood kraft were prepared using a dynamic sheet former. The sheets were pressed with two different orientations; aligned with the felt aligned in the machine direction or with web aligned in the cross direction. The wet web samples were immediately transferred after pressing to a hot plate and dried under restraint. A bench-scale method was developed using near infrared (NIR) imaging in order to characterise the interaction between felt and web structure during pressing and drying. It was found that the average press dryness had a low dependence on interactions between web and felt structure. Moisture variability in the interaction layer was found to be highly dependent on the web fibre orientation relative to the press felt. High levels of moisture variability on the web surface were observed with large differences in fibre alignment. It was observed that moisture variations in the web surface after pressing continued through the drying process and further increased the total drying time of the paper web.

  • 29.
    Lindberg, Anders
    et al.
    KTH Royal institute of technology, Sweden.
    Alfthan, Johan
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Pettersson, Henrik
    RISE - Research Institutes of Sweden, Bioekonomi, Biobaserade material.
    Flodberg, Göran
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Yang, Li
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Mechanical performance of polymer powder bed fused objects: FEM simulation and verification2018Ingår i: Additive manufacturing, ISSN 2214-8604, Vol. 24, s. 577-586Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Additive manufacturing (3D printing) enables the designing and producing of complex geometries in a layer-by-layer approach. The layered structure leads to anisotropic behaviour in the material. To accommodate anisotropic behaviour, geometrical optimization is needed so that the 3D printed object meets the pre-set strength and quality requirements. In this article a material description for polymer powder bed fused also or selective laser sintered (SLS) PA12 (Nylon-12), which is a common 3D printing plastic, was investigated, using the Finite Element Method (FEM). The Material Model parameters were obtained by matching them to the test results of multipurpose test specimens (dumb-bells or dog bones) and the model was then used to simulate/predict the mechanical performance of the SLS printed lower-leg prosthesis components, pylon and support. For verification purposes, two FEM designs for a support were SLS printed together with additional test specimens in order to validate the used Material Model. The SLS printed prosthesis pieces were tested according to ISO 10328 Standard. The FEM simulations, together with the Material Model, was found to give good estimations for the location of a failure and its load. It was also noted that there were significant variations among individual SLS printed test specimens, which impacted on the material parameters and the FEM simulations. Hence, to enable reliable FEM simulations for the designing of 3D printed products, better control of the SLS process with regards to porosity, pore morphology and pore distribution is needed.

  • 30.
    Lo Re, Giada
    et al.
    KTH Royal Institute of Technology, Sweden.
    Spinella, Stephen
    NYU Tandon School of Engineering, USA.
    Boujemaoui, Assya
    KTH Royal Institute of Technology, Sweden.
    Vilaseca, Fabiola
    University of Girona, Italy.
    Larsson, Per Tomas
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi. KTH Royal Institute of Technology, Sweden.
    Adås, Fredrik
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Berglund, Lars A.
    KTH Royal Institute of Technology, Sweden.
    Poly(ϵ-caprolactone) Biocomposites Based on Acetylated Cellulose Fibers and Wet Compounding for Improved Mechanical Performance2018Ingår i: ACS Sustainable Chemistry and Engineering, ISSN 2168-0485, Vol. 6, nr 5, s. 6753-6760Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Poly(ϵ-caprolactone) (PCL) is a ductile thermoplastic, which is biodegradable in the marine environment. Limitations include low strength, petroleum-based origin, and comparably high cost. Cellulose fiber reinforcement is therefore of interest although uniform fiber dispersion is a challenge. In this study, a one-step wet compounding is proposed to validate a sustainable and feasible method to improve the dispersion of the cellulose fibers in hydrophobic polymer matrix as PCL, which showed to be insensitive to the presence of the water during the processing. A comparison between unmodified and acetylated cellulosic wood fibers is made to further assess the net effect of the wet feeding and chemical modification on the biocomposites properties, and the influence of acetylation on fiber structure is reported (ATR-FTIR, XRD). Effects of processing on nanofibrillation, shortening, and dispersion of the cellulose fibers are assessed as well as on PCL molar mass. Mechanical testing, dynamic mechanical thermal analysis, FE-SEM, and X-ray tomography is used to characterize composites. With the addition of 20 wt % cellulosic fibers, the Young's modulus increased from 240 MPa (neat PCL) to 1850 MPa for the biocomposites produced by using the wet feeding strategy, compared to 690 MPa showed for the biocomposites produced using dry feeling. A wet feeding of acetylated cellulosic fibers allowed even a greater increase, with an additional 46% and 248% increase of the ultimate strength and Young's modulus, when compared to wet feeding of the unmodified pulp, respectively. 

  • 31.
    Lundqvist, Sven- Olof
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar. IIC, Sweden.
    Seifert, Stefan
    Scientes Mondium UG, Germany.
    Grahn, Thomas
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Olsson, Lars
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Garci­a-Gil, Maria Rosario
    SLU Swedish University of Agricultural Sciences, Sweden.
    Karlsson, Bo
    Skogforsk, Sweden.
    Seifert, Thomas
    Scientes Mondium UG, Germany; Stellenbosch University, South Africa.
    Age and weather effects on between and within ring variations of number, width and coarseness of tracheids and radial growth of young Norway spruce2018Ingår i: European Journal of Forest Research, ISSN 1612-4669, E-ISSN 1612-4677, Vol. 137, nr 5, s. 719-743Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Annual growth, fibre and wood properties of Norway spruce are all under strong influence from genetics, age and weather. They change dynamically, particularly at young ages. Most genetic research and tree improvement programs are based on data from this most dynamic phase of the life of trees, affected by differences in weather among sites and years. In the work presented, influences of age and weather were investigated and modelled at the detail of annual rings and at the sub-tree ring level of earlywood, transitionwood and latewood. The data used were analysed from increment cores sampled at age 21 years from almost 6000 Norway spruce trees of known genetic origin, grown on two sites in southern Sweden. The traits under investigation were radial growth, cell widths, cell numbers, cell wall thickness and coarseness as a measure of biomass allocation at cell level. General additive mixed models (GAMMs) were fitted to model the influences of age, local temperature and precipitation. The best models were obtained for number of tracheids formed per year, ring width, average radial tracheid width in earlywood, and ring averages for tangential tracheid width and coarseness. Considering the many sources behind the huge variation, the explained part of the variability was high. For all traits, models were developed using both total tree age and cambial age (ring number) to express age. Comparisons indicate that the number of cell divisions and ring width are under stronger control of tree age, but the other traits under stronger control of cambial age. The models provide a basis to refine data prior to genetic evaluations by compensating for estimated differences between sites and years related to age and weather rather than genetics. Other expected applications are to predict performance of genotypes in relation to site or climate and simulation of climate change scenarios.

  • 32.
    Lundqvist, Sven-Olof
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Grahn, Thomas
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Olsson, Lars
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Seifert, Thomas
    Stellenbosch University, South Africa.
    Comparison of wood, fibre and vessel properties of drought-tolerant eucalypts in South Africa2017Ingår i: Southern Forests, a journal of forest science, ISSN 2070-2620, E-ISSN 2070-2639, Vol. 79, nr 3, s. 215-223Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Three drought-tolerant eucalypt genotypes have been investigated for a broad spectrum of properties to provide a basis for comparison on their suitability for various end-uses. The genotypes included were a Eucalyptus grandis × E. camaldulensis hybrid, E. gomphocephala and E. cladocalyx, selected based on previous studies that indicated good potential to tolerate arid conditions, reasonably good volume growth and straightness of stems. In this study, information was added on differences between species and parts of stems in growth (volume and biomass) and properties of wood (density and stiffness), fibres (dimensions and microfibril angle) and vessels (size and numbers). We found high wood densities and stiffness values for E. cladocalyx and E. gomphcephala, making them suitable for construction wood. Logs from the mid-part of the stem had the best timber properties, as the butt logs showed the highest microfibril angle and lowest wood stiffness due to longitudinal juvenility. Such juvenility was also to some degree observed for wood density and fibre length. The information gained will be especially helpful for selecting species and processing options for small farm and community plantations for producing higher-value products that may be sold to generate much-needed income as well as for local uses, such as fuelwood and charcoal. © 2017 The Authors

  • 33.
    Magnusson, Mikael
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Holmqvist, Claes
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Textile-like materials with foam forming on a paper machine2019Ingår i: PaperCon 2019: Proceedings, TAPPI Press, 2019, artikel-id PF3.2Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Research has been carried out into the possibility of producing a paper with textile-like characteristics on a paper machine. The furnish used consisted of a mixture of 25% bleached softwood kraft pulp refined to 30 SR, 25% dissolving pulp and 50% synthetic fibres. The latter fraction consisted of 15% sort-cut (4mm) polylactic acid (PLA) fibres and 35% viscose fibres cut to 5-8mm. A commercial surfactant was used as foaming aid and sheets were formed on a pilot machine from a bubbly dispersion (foam forming). A production method was developed in which the synthetic fibres were only injected intermittently into the pulp flow. Sheets containing 35% of 8mm long viscose fibres, 25% kraft pulp, 25% dissolving pulp and 15% of 4mm long PLA fibres were successfully produced. Sheets had good formation with furnish air fractions as low as 25%. The sheets made from the mixture of kraft pulp and synthetic fibres had softness comparable with facial wipes and other tissue products while also having significantly higher tensile strength. Proactive adjustment of the surfactant addition enabled the surface tension and the forming process to be stably maintained during the sudden changes in the fibre feed flows.

  • 34.
    Marin, Gustav
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Nygårds, Mikael
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Box compression strength of packages in different climates2019Ingår i: 29th IAPRI Symposium on packaging, 2019: Serving society innovative perspectives on packaging, 2019Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Packages made of five folding box boards made on the same paperboard machinehave been analysed. The paperboards were from the same product series but had different grammage (235, 255, 270, 315, 340 g/m2) and different bending stiffness. Thepaperboards are normally used to make packages, and since the bending stiffnessand grammage varies the packages performance will be different. In this study, twodifferent load cases were defined and Box Compression Tests (BCT) were performedat different levels of relative humidity (30, 50, 70, 90 % RH) and were evaluated as afunction of moisture ratio.The result showed a linear relation between the box compression strength and themoisture ratio. In addition, when the data was normalized with the measurements forthe standard climate (50 % RH) and was evaluated as a function of moisture ratio, theresult indicated that the normalized box compression strength for all the paperboardsand both of the load cases could be expressed as a linear function of moisture, dependent of two constants a and b.Consequently, the study indicates that it is possible to estimate the Box compressionstrength at different climates of a package made of paperboard, by knowing the boxcompression strength for the standard climate (50 % RH and 23 °C) and the constantsa and b.

  • 35.
    Marin, Gustav
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Nygårds, Mikael
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Östlund, Sören
    KTH Royal Institute of Sweden, Sweden.
    Stiffness and strength properties of five paperboards and their moisture dependency2019Ingår i: International Paper Physics Conference 2019, Indianapolis, IN, USA, 5-8 May 2019: preprint proceedings, TAPPI Press, 2019, s. 14-29Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Research has been undertaken to characterise the in-plane and out-of-plane stiffness and strength properties of paperboards to enable data for use in determining constitutive parameters needed in finite element simulations. Paperboards with different bending stiffness were analysed, using five folding box boards of varying grammage (235, 255, 270, 315 and 340gsm). The stiffness and strength properties were determined at different relative humidity (RH), namely, 20, 50, 70 and 90%. As well as in-plane tensile test and out-of-plane tensile test, the short-span compression test (SCT) was carried out, together with bending stiffness test and double-notch shear test. The results revealed a linear relation between mechanical properties and moisture ratio for each paperboard. When the data were normalised with data for the standard climate (50% RH) and investigated as a function of moisture ratio, it was determined that the normalised mechanical properties for all paperboards coincided along one single line. Thus they could be expressed as a linear function of moisture ratio and two constants. It has been concluded that by knowing the structural properties for the preferred level of RH and the mechanical property for the standard climate, the mechanical properties of a paperboard could be obtained.

  • 36.
    Mitraka, Evangelia
    et al.
    Linköping University, Sweden.
    Vagin, Mikhail
    Linköping University, Sweden.
    Sjöstedt, Anna
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Berggren, Magnus
    Linköping University, Sweden.
    Håkansson, Karl
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Jonsson, Magnus
    Linköping University, Sweden.
    Crispin, Xavier
    PEDOT-Cellulose Gas Diffusion Electrodes for Disposable Fuel Cells2019Ingår i: Advanced Sustainable Systems, ISSN 2366-7486, Vol. 3, nr 12, artikel-id 1900097Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The mass implementation of renewable energy sources is limited by the lack of energy storage solutions operating on various timescales. Electrochemical technologies such as supercapacitors and batteries cannot handle long storage time because of self-discharge issues. The combination of fuel storage technology and fuel cells is an attractive solution for long storage times. In that context, large-scale fuel cell solutions are required for massive energy storage in cities, which leads to possible concepts such as low-cost disposable fully organic membrane assemblies in fuel cells to avoid regeneration of expensive poisoned electrodes. Here, the formation of an organic gas diffusion electrode (GDE) fabricated by paper-making production, combined with in situ polymerization is demonstrated for the first time. Cellulose is used as a 3D scaffold functionalized with poly(3,4-ethylenedioxythiophene) (PEDOT) serving as both an electrical conductor and an electrocatalyst of high efficiency for the oxygen reduction reaction. The PEDOT-cellulose porous GDE is implemented in a membrane assembly and demonstrated in a H2-O2 fuel cell. The demonstration of low-cost material/manufacturing that is environmentally friendly is a paradigm shift in the development of fuel cells for a sustainable society.

  • 37.
    Mo, Lixin
    et al.
    Beijing Institute of Graphic Communication, China.
    Guo, Zhenxin
    Beijing Institute of Graphic Communication, China.
    Wang, Zhenguo
    Beijing Institute of Graphic Communication, China.
    Yang, Li
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Fang, Yi
    Beijing Institute of Graphic Communication, China.
    Xin, Zhiqing
    Beijing Institute of Graphic Communication, China.
    Li, Xiu
    Beijing Institute of Graphic Communication, China.
    Chen, Yinjie
    Beijing Institute of Graphic Communication, China.
    Cao, Meijuan
    Beijing Institute of Graphic Communication, China.
    Zhang, Qingqing
    Beijing Institute of Graphic Communication, China.
    Li, Luhai
    Beijing Institute of Graphic Communication, China.
    Nano-Silver Ink of High Conductivity and Low Sintering Temperature for Paper Electronics2019Ingår i: Nanoscale Research Letters, ISSN 1931-7573, E-ISSN 1556-276X, Vol. 14, artikel-id 197Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Highly conductive ink with low sintering temperature is important for printed electronics on paper substrate. Silver nanoparticles (Ag NPs) of different average radii ranging from 48 to 176 nm were synthesized by adjusting the Ag+ concentration in the reaction process. The electric resistivity of the Ag NP-based ink film in relation to Ag NP size, sintering temperature, amount of PVP capping agent on Ag NP surface, and morphology evolution of the film during heating process was investigated. It was found that the resistivity of the films reduced very rapidly with increasing particle size due above all to reduced amount of protective agent capping on the Ag NPs. A semi-empirical relationship between the resistivity and the particle size was proposed. With the help of this mathematical expression, one gains both systematic and detailed insight to the resistivity evaluation with regard to the Ag particle size. The optimal electric resistivity of 4.6 μΩ cm was achieved at 140 °C for 10 min which was very close to the resistivity value of bulk Ag (1.58 μΩ cm). Mechanical flexibility of the printed electronics with the Ag NP-based ink on paper substrates was investigated. The prints on the art coated paper exhibited better flexibility compared to that on the photopaper. This might be attributed to the surface coating composition, surface morphology of the paper, and their corresponding ink absorption property. © 2019, The Author(s).

  • 38.
    Mo, Lixin
    et al.
    Beijing Institute of Graphic Communication, China.
    Guo, Zhenxin
    Beijing Institute of Graphic Communication, China.
    Zhang, Qingqing
    Beijing Institute of Graphic Communication, China.
    Fang, Yi
    Beijing Institute of Graphic Communication, China.
    Xin, Zhiqing
    Beijing Institute of Graphic Communication, China.
    Hu, Kun
    Beijing Institute of Graphic Communication, China.
    Han, Lu
    Beijing Institute of Graphic Communication, China.
    Li, Luhai
    Beijing Institute of Graphic Communication, China.
    Yang, Li
    RISE - Research Institutes of Sweden (2017-2019), Bioekonomi, Papperstillverkning och förpackningar.
    Chen, Zheng
    Shine Optoelectronics (Kunshan) Co Ltd, China.
    Silver Nanoparticles Based Ink with Moderate Sintering in Flexible and Printed Electronics2019Ingår i: International Journal of Molecular Sciences, ISSN 1422-0067, E-ISSN 1422-0067, Vol. 20, nr 9Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Printed electronics on flexible substrates has attracted tremendous research interest research thanks its low cost, large area production capability and environmentally friendly advantages. Optimal characteristics of silver nanoparticles (Ag NPs) based inks are crucial for ink rheology, printing, post-print treatment, and performance of the printed electronics devices. In this review, the methods and mechanisms for obtaining Ag NPs based inks that are highly conductive under moderate sintering conditions are summarized. These characteristics are particularly important when printed on temperature sensitive substrates that cannot withstand sintering of high temperature. Strategies to tailor the protective agents capping on the surface of Ag NPs, in order to optimize the sizes and shapes of Ag NPs as well as to modify the substrate surface, are presented. Different (emerging) sintering technologies are also discussed, including photonic sintering, electrical sintering, plasma sintering, microwave sintering, etc. Finally, applications of the Ag NPs based ink in transparent conductive film (TCF), thin film transistor (TFT), biosensor, radio frequency identification (RFID) antenna, stretchable electronics and their perspectives on flexible and printed electronics are presented.

  • 39.
    Mojzes, Akos
    et al.
    Széchenyi István University, Hungary.
    Trost, Thomas
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Vörösköi, Kata
    Széchenyi István University, Hungary.
    Drop Performance of Dangerous Goods Packages in the Aspect of Parcel Delivery Standards2018Ingår i: Packaging: Driving a sustainable future, 2018, s. 569-577Konferensbidrag (Refereegranskat)
    Abstract [en]

    Requirements for dangerous goods packaging are well known, whatever version are used. The testing circumstances are strictly defined for each transportation method (road, rail, air, sea). But nowadays it is becoming a practice that courier express operators transport dangerous goods as single package. This parcel delivery method means a higher risk for all kind of logistics participants. By this service the packages are delivered fast, but handled more roughly than in comparison to LTL (less than truckload) or FTL (full truck load). Naturally, the parcel delivery sector uses its own suitability testing methods, which are also well defined. These procedures are coming from various standards such as ASTM, ISTA or corporate (FedEx) standards.This paper compares the most common parcel delivery testing conditions concerning the drop test requirements of DGR (Dangerous Goods Regulation) using packaging such as paper bag, corrugated fibreboard box, steel drum and plastic jerrycan, respectively. Then the test results were analyzed to present the differences.

  • 40.
    Nordström, Bengt
    et al.
    SCA, Sweden.
    Hermansson, Lennart
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Effect of machine speed on formation and strength efficiency in twin-wire roll forming of never-dried unbleached softwood kraft pulp2018Ingår i: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 33, nr 2, s. 271-278Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    There is a constant drive to increase machine speed in the production of kraftliner and most other major paper grades, but the separate effect of the machine speed on the paper properties has been unclear. The effect of machine speed in twin-wire roll forming of never-dried unbleached softwood kraft pulp was evaluated here in a pilot machine investigation by examining three machine speed levels (500, 750, and 1000 m/min) over a series of jet-to-wire speed differences. Similar headbox consistency and draw from wire section to winding were employed at the different machine speed levels. An increase in the machine speed had a favorable effect on formation and Z-strength efficiency over a wide range of jet-to-wire speed differences, whereas the machine speed had an insignificant effect on tensile strength efficiency and tensile stiffness efficiency. For all properties, the overall shape of the jet-to-wire speed difference curve remained similar when changing the machine speed.

  • 41.
    Nordström, Bengt
    et al.
    SCA R&D, Sweden.
    Hermansson, Lennart
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Effect of softwood kraft fiber coarseness on formation and strength efficiency in twin-wire roll forming2018Ingår i: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 33, nr 2, s. 237-245Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    It has been unclear how fiber coarseness affect formation and the utilization of furnish strength in the machine-made paper (strength efficiency). In this work, the effect of softwood kraft fiber coarseness on formation and strength efficiency in twin-wire roll forming was examined in a pilot machine investigation. A reduction in softwood kraft fiber coarseness from 0.21 to 0.17 mg/m, associated with a reduction in fiber grammage from 6.2 to 5.2 g/m2, was found to have no significant effect on formation at the point of minimum shear during dewatering. The insignificant effect of reduced coarseness can be interpreted as the net result of two effects, namely, an increase in the number of fiber layers at a given grammage (favorable) and an increase in the flocculation tendency (unfavorable). While the effect of coarseness was negligible at the point of minimum shear, coarser fibers enabled larger improvement in formation through the jet-to-wire speed difference. In correspondence to the insignificant effect on formation, fiber coarseness had a negligible effect on tensile strength efficiency and Z-strength at the point of minimum shear. The larger improvement in formation through the jet-to-wire speed difference for the coarser fibers was reflected in a favorable effect on Z-strength efficiency.

  • 42.
    Nordström, Bengt
    et al.
    SCA, Sweden.
    Hermansson, Lennart
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Successive twin-wire roll forming of two-ply paper with softwood kraft pulp and recycled pulp - Effect of kraftply formation on Z-strength2017Ingår i: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 32, nr 4, s. 639-645Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Kraftliner and kraft-top liner typically consists of two or more plies that are formed separately and combined by couching. The Z-strength tends to be limited by the ply adhesion, and the softwood kraft pulp used is commonly refined beyond the optimum for tensile strength to ensure sufficient Z-strength. In this work, two-ply forming by successive twin-wire roll forming, was evaluated with moderately refined never-dried unbleached softwood kraft pulp and recycled pulp in different plies. Successive twin-wire roll forming involved two-sided roll forming of the first ply and onesided roll forming of the second ply directly onto the first ply. Two-sided roll forming of the recycled pulp and onesided roll forming of the kraft pulp was evaluated in parallel to the reversed combination. The Z-strength was found to be limited by the strength of the kraft ply rather than by the ply adhesion. The effect on Z-strength when changing headbox consistency or when going from one-sided to two-sided roll forming for the kraft ply was in agreement with results for single-ply forming. Besides the favorable findings for Z-strength, the results suggest that successive roll forming enables an efficient utilization of the tensile strength potential of the softwood kraft pulp. 

  • 43.
    Nygårds, Mikael
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Sjökvist, Stefan
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Marin, Gustav
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Sundström, Jonas
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Simulation and experimental verification of a drop test and compression test of a Gable top package2019Ingår i: 29th IAPRI Symposium on packaging, 2019: Serving society innovative perspectives on packaging, 2019Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

     A finite element framework has been proposed that can be used to simulateboth empty paperboard packages and package filled with plastic granulates. A Gabletop package was made of a commercial paperboard, and material properties neededin the material model was determined. Two simulations were performed, a drop testand a compression test. By comparison between experimental and numerical results,the deformation mechanisms at impact could be identified and correlated to materialproperties. When the package was filled with granulates different mechanisms wasactivated compared to an empty package. The granulates contribute to bulging ofthe panels, such that the edges became more load bearing compared to the panels.When the edges carried the loads the importance of the out-of-plane properties alsoincreased, and local failure initiation related to delamination was observed. Comparison between experimental and numerical impact forces show that there are still important things to consider in the model generation, e.g. variation of properties withinthe package, which originate both from material property variations and the loadinghistory, e.g. during manufacturing and handling.

  • 44.
    Nygårds, Mikael
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Bioekonomi, Papperstillverkning och förpackningar.
    Sjökvist, Stefan
    RISE - Research Institutes of Sweden (2017-2019), Bioekonomi, Papperstillverkning och förpackningar.
    Marin, Gustav
    RISE - Research Institutes of Sweden (2017-2019), Bioekonomi, Papperstillverkning och förpackningar.
    Sundström, Jonas
    RISE - Research Institutes of Sweden (2017-2019), Bioekonomi, Papperstillverkning och förpackningar.
    Simulation and experimental verification of a drop test and compression test of a gable top package2019Ingår i: Packaging technology & science, ISSN 0894-3214, E-ISSN 1099-1522, Vol. 32, nr 7, s. 325-333Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A finite element framework has been proposed that can be used to simulate both empty paperboard packages and package filled with plastic granulates. A gable top package was made of a commercial paperboard, and material properties needed in the material model were determined. Two simulations were performed, a drop test and a compression test. By comparison between experimental and numerical results, the deformation mechanisms at impact could be identified and correlated to material properties. When the package was filled with granulates, different mechanisms was activated compared with an empty package. The granulates contribute to bulging of the panels, such that the edges became more load bearing compared with the panels. When the edges carried the loads, the importance of the out-of-plane properties also increased, and local failure initiation related to delamination was observed. Comparison between experimental and numerical impact forces shows that there are still important things to consider in the model generation, eg, variation of properties within the package, which originate both from material property variations, and the loading history, eg, during manufacturing and handling.

  • 45.
    Odeberg Glasenapp, Astrid
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Alfthan, Johan
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Salmen, Lennart
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Stevanic Srndovic, Jasna
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Björk, Elisabeth
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Holmqvist, Claes
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Yang, Li
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Berthold, Jesper
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Next level of corrugated board research2019Ingår i: 29th IAPRI Symposium on packaging, 2019: Serving society innovative perspectives on packaging, 2019Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

     For the first time in the Bioeconomy research program at RISE, corrugatedboard has an own research area. Research is building around the main driving forcesin the corrugated board value chain like e-commerce, improved box performance anddigital printing. The main weakness of corrugated board, its moisture sensitivity, isalso addressed.These main driving forces and weaknesses of corrugated board are mirrored in thethemes of this large research program area:Fibre sorption and deformation mechanismsFundamental knowledge on the mechanisms behind moisture sorption and deformation on fibre level is developed to increase moisture and creep resistance throughmodification of paper materials. State of the art methods for characterization ofthe fibre ultra- and nano-structure such as Fourier transform infra-red spectroscopy(FTIR), small angle X-ray scattering (SAXS), and wide angle X-ray scattering (WAXS)give new insights on mechanisms and clarify effects of moisture as well as chemicalmodifications.Papermaking for improved base sheetsConcepts that are explored are fibre-based strength additives produced with novelrefining techniques, and modified ZD-profiles in the sheet for better mechanical properties.Box mechanicsMechanical performance of structures such as corrugated board boxes can be predicted through physically based mathematical modelling by taking the behaviour ofthe constituent materials as well as the geometry into account. Appropriate materialmodels for the corrugated board are identified and finite element models for simulation of corrugated board packaging performance are developed.Tool for inkjet printability on corrugatedThere is a genuine need for improved inkjet printability on corrugated materials thanksto rapid development in e-commerce as well as digitalization along the corrugatedvalue chain. Effective measurement methods and knowledge around ink-substrateinteractions are developed to enable board producers and converters to have effective product development and predictable printability on not only liners but also oncorrugated materials.

  • 46.
    Odeberg Glasenapp, Astrid
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Sundin, Maria
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Nordlinder, J.
    Swedish Patent- and Registration Office, Sweden.
    Berthold, Jesper
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Alfthan, Johan
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Water-free bonding of corrugated board2018Ingår i: 21st IAPRI World Conference on Packaging 2018: Packaging: Driving a Sustainable Future, DEStech Publications Inc. , 2018, s. 608-616Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    The "water-free bonding of corrugated board" concept focuses on the development, waste management and market potential of a new corrugated board production method. It has earlier been shown that by integrating PLA into paper, certain mechanical properties of corrugated board papers can be enhanced. These enhanced papers have been used for producing corrugated board. Corrugated board is usually produced by gluing the corrugated board paper layers with a starch suspension. This process is reducing the mechanical paper strength and is also energy consuming, as the water added by the starch suspension in the process has to be evaporated. In this study, two new water-free joining techniques for corrugated board have been investigated: PLA-welding, which melts the inherent PLA of the paper to create a bond and using PLA as an adhesive. Both techniques have shown promising results and are recommended for further investigation, however, replacing starch glue with PLA seems to be a solution closer to the market. For the material to fit in a future circular economy it is important that the waste is managed in a way that is sustainable for the environment and the society. Repulpability testing in combination with literature studies indicate that the new material would be possible to recycle, and that the new material could function in every step described in the EU Waste Framework Directive.

  • 47.
    Odeberg Glasenapp, Astrid
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Sundin, Maria
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Nordlinder, Johanna
    Swedish patent- and registration office, Sweden.
    Berthold, Jesper
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Alfthan, Johan
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Water-free bonding of corrugated board2018Ingår i: Packaging: Driving a sustainable future / [ed] Wang S-W, 2018, s. 608-616Konferensbidrag (Refereegranskat)
    Abstract [en]

    The "water-free bonding of corrugated board" concept focuses on thedevelopment, waste management and market potential of a new corrugated board production method. It has earlier been shown that by integrating PLA into paper, certain mechanical properties of corrugated board papers can be enhanced. These enhanced papers have been used for producing corrugated board. Corrugated board is usually produced by gluing the corrugated board paper layers with a starch suspension. This process is reducing the mechanical paper strength and is also energy consuming, as the water added by the starch suspension in the process has to be evaporated. In this study, two new water-free joining techniques for corrugated board have been investigated: PLA-welding, which melts the inherent PLA of the paper to create a bond and using PLA as an adhesive. Both techniques have shown promising results and are recommended for further investigation, however, replacing starch glue with PLA seems to be a solution closer to the market. For the material to fit in a future circular economy it is important that the waste is managed in a way that is sustainable for the environment and the society. Repulp ability testing in combination with literature studies indicate that the new material would be possible to recycle, and that the new material could function in every step described in the EU Waste Framework Directive.

  • 48.
    Pjanic, P
    et al.
    Ecole Polytechnique Federale de Lausanne, Switzerland.
    Yang, Li
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Teleman, Anita
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Hersch, R.D.
    Ecole Polytechnique Federale de Lausanne, Switzerland.
    Angular Color Prediction Model for Anisotropic Halftone Prints on a Metallic Substrate2019Ingår i: Journal of Imaging Science and Technology, ISSN 1062-3701, E-ISSN 1943-3522, Vol. 63, nr 4, s. 040407-1-040407-11Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Under specular reflection, non-isotropic halftones such as line halftones printed on an ink-receiving plastic layer superposed with a metallic layer change their colors upon in-plane rotation of the print. This color change is due to the orientation-dependent optical dot gain of the halftone. A strong dot gain occurs when the incident light is perpendicular to the halftone line structure. A color prediction model is proposed which predicts under specular reflection the color of cyan, magenta and yellow line halftones as a function of the azimuthal rotation angle, the incident angle and the line frequency. The model is calibrated by measuring 17 reflectances at the (25 : 25) measurement geometry, with the incident light parallel to the halftone lines. The model has been tested for several azimuthal rotation and incident viewing angles, each time for 125 different cyan, magenta and yellow ink surface coverages.

  • 49.
    Ratke, Christine
    et al.
    SLU Swedish University of Agricultural Sciences, Sweden.
    Terebieniec, Barbara K
    SLU Swedish University of Agricultural Sciences, Sweden.
    Winestrand, Sandra
    Umeå University, Sweden.
    Derba-Maceluch, Marta
    SLU Swedish University of Agricultural Sciences, Sweden.
    Grahn, Thomas
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Schiffthaler, Bastian
    Umeå University, Sweden.
    Ulvcrona, Thomas
    SLU Swedish University of Agricultural Sciences, Sweden.
    Özparpucu, Merve
    Swiss Federal Institute of Technology (ETH Zürich), Switzerland.
    Rüggeberg, Markus
    Swiss Federal Institute of Technology (ETH Zürich), Switzerland.
    Lundqvist, Sven-Olof
    RISE - Research Institutes of Sweden, Bioekonomi.
    Street, Nathaniel R
    Umeå University, Sweden.
    Jönsson, Leif J
    Umeå University, Sweden.
    Mellerowicz, Ewa J
    SLU Swedish University of Agricultural Sciences, Sweden.
    Downregulating aspen xylan biosynthetic GT43 genes in developing wood stimulates growth via reprograming of the transcriptome2018Ingår i: New Phytologist, ISSN 0028-646X, E-ISSN 1469-8137, Vol. 219, nr 1, s. 230-245Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Xylan is one of the main compounds determining wood properties in hardwood species. The xylan backbone is thought to be synthesized by a synthase complex comprising two members of the GT43 family. We downregulated all GT43 genes in hybrid aspen (Populus tremula × tremuloides) to understand their involvement in xylan biosynthesis. All three clades of the GT43 family were targeted for downregulation using RNA interference individually or in different combinations, either constitutively or specifically in developing wood. Simultaneous downregulation in developing wood of the B (IRX9) and C (IRX14) clades resulted in reduced xylan Xyl content relative to reducing end sequence, supporting their role in xylan backbone biosynthesis. This was accompanied by a higher lignocellulose saccharification efficiency. Unexpectedly, GT43 suppression in developing wood led to an overall growth stimulation, xylem cell wall thinning and a shift in cellulose orientation. Transcriptome profiling of these transgenic lines indicated that cell cycling was stimulated and secondary wall biosynthesis was repressed. We suggest that the reduced xylan elongation is sensed by the cell wall integrity surveying mechanism in developing wood. Our results show that wood-specific suppression of xylan-biosynthetic GT43 genes activates signaling responses, leading to increased growth and improved lignocellulose saccharification.

  • 50.
    Rättö, Peter
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Dahlman, Olof
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Junel, Kristina
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Pilot coating with a hemicellulose-based barrier2018Ingår i: PaperCon 2018: Shaping the future through innovation, TAPPI , 2018, artikel-id FF1.3Konferensbidrag (Refereegranskat)
    Abstract [en]

    A hemicellulose-based barrier formulation was produced from wood chips to pilot coating application in a bladecoater. The development process is described from a project planning point of view with network plan and decisionpoints.Different hemicelluloses were produced and compared in the research laboratory. Oxygen barrier properties fromfilms and rheology of water suspensions were evaluated for different laboratory produced hemicelluloses originatingfrom wood chips or from kraft pulps. The viscosity at low and high shear rates were evaluated. From these results,hemicellulose produced from birch wood chips was chosen.Hemicellulose was then produced at in kg quantities. The hemicellulose was produced employing pre-hydrolysistreatment of birch wood chips. The concentration of hemicellulose pre-hydrolyses was increased from 3.3% to11.5% by membrane filtration. The barrier properties of the hemicellulose coated material were evaluated inlaboratory scale. A pre-coating was also evaluated in laboratory scale.Trials were performed at Iggesund PaperBoard in their pilot scale coater. A pre-coating was applied during the firstday, and the hemicellulose-based coating was applied on the second day. The pilot trials went well without anylarger obstacles. Quick barrier evaluations showed that the hemicellulose-based barrier coating had a good greaseresistance even if the coating consumption during the trials indicated a low application grammage.

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