Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Fast and reliable quantification of lignin reactivity via reaction with dimethylamine and formaldehyde (Mannich reaction)
RISE, Innventia. RISE - Research Institutes of Sweden, Bioeconomy. KTH Royal Institute of Technology, Sweden.
RISE, Innventia. RISE - Research Institutes of Sweden, Bioeconomy.ORCID iD: 0000-0002-4858-7352
RISE, Innventia. RISE - Research Institutes of Sweden, Bioeconomy. KTH Royal Institute of Technology, Sweden.
2017 (English)In: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 71, no 1, 27-34 p.Article in journal (Refereed) Published
Abstract [en]

The influence of pH on the Mannich reaction (amino alkylation in the presence of formaldehyde) has been analyzed by liquid chromatography-mass spectrometry (LC-MS) with vanillin (VA) as a model compound and a purified softwood kraft lignin (SKL) as a substrate. The reaction products of VA were studied at pH 5, 7, and 9 at 60°C for 4 h. The Mannich adduct and side reaction products with methylene bridge were found at both pH 7 and 9, while only di-substituted by-products were observed at pH 5. Nitrogen contents determined from blank runs were substantial at pH 5 and negligible at pH 7. In VA or SKL, the resulting N-contents at pH 7 corresponded to a 76 or 62 mol% of the theory, respectively, i.e. based on the available C5 positions in phenolic guaiacyl units (G-units). In the case of SKL, 31P-NMR analysis confirmed a 77% conversion of all phenolic G-units into their C5 substituted derivatives. The Mannich reaction should be performed on lignin at pH 7 for 1 h to suppress unwanted side reactions, which could be observed by LC-MS under other pH conditions. The reaction is suitable for fast and reliable determination of reactive C5-positions in lignin by multiplication of the N-content of the reaction products with a factor of 1.6.

Place, publisher, year, edition, pages
2017. Vol. 71, no 1, 27-34 p.
Keyword [en]
Amination, Chemical reactions, Formaldehyde, Liquid chromatography, Mass spectrometry, Nitrogen, Organic polymers, Reaction products, Reactivity (nuclear)
National Category
Paper, Pulp and Fiber Technology
Identifiers
URN: urn:nbn:se:ri:diva-28194DOI: 10.1515/hf-2016-0054Scopus ID: 2-s2.0-85008709552OAI: oai:DiVA.org:ri-28194DiVA: diva2:1074885
Note

cited By 0

Available from: 2017-02-16 Created: 2017-02-16 Last updated: 2017-10-27Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Search in DiVA

By author/editor
Sjöholm, Elisabeth
By organisation
InnventiaBioeconomy
In the same journal
Holzforschung
Paper, Pulp and Fiber Technology

Search outside of DiVA

GoogleGoogle Scholar

Altmetric score

Total: 19 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
v. 2.28.0