Eco-friendly high-strength composites based on hot-pressed lignocellulose microfibrils or fibers
2021 (English)In: ACS Sustainable Chemistry and Engineering, E-ISSN 2168-0485, Vol. 9, no 4, p. 1899-1910Article in journal (Refereed) Published
Abstract [en]
Unbleached lignocellulosic wood fiber materials of low porosity are of great interest as eco-friendly load-bearing materials because their yield is much higher than that for “pure” wood cellulosics. The difference between comparable materials based on lignocellulose fibers or nanocellulose is investigated. The structure, surface area, mechanical properties, moisture sorption, and optical properties of films based on fibers or microfibrillated lignocellulose (MFLC) were characterized as a function of lignin content, and the environmental impact was compared. The modulus and tensile strength of comparable fiber and MFLC films (≈25% porosity) increased up to an optimum lignin content (11−17%) and then decreased at a very high lignin content. Hot-pressed MFLC films with little porosity showed excellent properties, 230−260 MPa strength, 17−20 GPa modulus, and 81 MPa wet strength. The mechanical property values of hot-pressed wood fibers with 25% porosity were also as high as 154 MPa strength and 13.2 GPa modulus, which are higher than those of comparable materials reported in the literature. Because hot-pressed lignocellulose fibers can be readily recycled and show low cumulative energy demand, they are candidates for semistructural engineering materials. MFLC is of great interest for coatings, films, adhesives, and as additives or in high-technology applications.
Place, publisher, year, edition, pages
American Chemical Society , 2021. Vol. 9, no 4, p. 1899-1910
Keywords [en]
Biocomposites, Mechanical properties, Microfibrillated cellulose, Moisture sorption, Nanocellulose, Recycling, Additives, Adhesives, Cellulose nanocrystals, Environmental impact, Environmental protection, Lignin, Lignocellulosic biomass, Optical properties, Porosity, Tensile strength, Wood products, Cumulative energy demands, Engineering materials, High-strength composites, High-technology applications, Lignin contents, Lignocellulosic woods, Load-bearing materials, Fibers
National Category
Natural Sciences
Identifiers
URN: urn:nbn:se:ri:diva-52455DOI: 10.1021/acssuschemeng.0c08498Scopus ID: 2-s2.0-85100272056OAI: oai:DiVA.org:ri-52455DiVA, id: diva2:1529368
Note
Funding details: Stiftelsen för Strategisk Forskning, SSF; Funding text 1: We acknowledge funding from the Swedish Foundation for Strategic Research, the STFI association of interested parties, and Treesearch support. LAB acknowledges funding from the KAW Biocomposites program.
2021-02-182021-02-182023-06-08Bibliographically approved