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. KTH Royal Institute of Technology, Stockholm, Sweden.
RISE, Innventia.
RISE, Innventia. KTH Royal Institute of Technology, Stockholm, 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-2016-0054ScopusID: 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: 2017-03-08Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus
By organisation
Innventia
In the same journal
Holzforschung
Paper, Pulp and Fiber Technology

Search outside of DiVA

GoogleGoogle Scholar

Altmetric score

Total: 12 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. 2.25.0