Lignins as macromonomers for polyurethanes synthesis: hydroxyl groups determination

• Type: Article in International Scientific Journal
• Date: 2008

Authors

Carolina Andreia Cateto (Author) FEUP; Maria Filomena Barreiro (Author) Other; Alírio Egídio Rodrigues (Author) FEUP; Marie Christine Brochier-Salon (Author) Other; Wim Thielemans (Author) Other; Mohamed Naceur Belgacem (Author) Other

Journal

Title: Journal of Applied Polymer Science

Vol. 109 No. 5

Pages: 3008-3017

ISSN: 0021-8995

Publisher: Wiley-Blackwell

Indexing

ISI Web of Science

Scopus

INSPEC

COMPENDEX

Scientific classification

FOS: Engineering and technology

CORDIS: Technological sciences > Engineering > Chemical engineering

Other information

DOI: DOI: 10.1002/app.28393

Abstract (EN): The hydroxyl group contents of four technical lignins [Indulin AT (Meadwestvaco), Alcell (Repap), Curan 27-11P (Borregaard LignoTech), and Sarkanda (Granit SA)] were investigated in view of their valorization as polyols in polyurethane synthesis. The different hydroxyl group contents were determined by the following methods: titration and H-1-NMR, C-13-NMR, and P-31- NMR spectroscopy. The titration method chosen was on the basis of a standard method commonly used to characterize commercial polyols for polyurethanes synthesis. The values of the total and phenolic hydroxyl contents determined by the different techniques were found to be in good agreement. For the total hydroxyl contents, coefficients of variation of 5.6% (Alcell), 3.2% (Indulin AT), 2.3% (Sarkanda), and 6.2% (Curan 27-11P) were established. For the phenolic hydroxyl contents, a good correlation was observed between data obtained from P-31-NMR and C-13- NMR for all lignin samples, except for the Sarkanda lignin, for which a relatively high coefficient of variation (12.6%) was found. For softwood lignins (Indulin AT and Curan 27-11P), the phenolic hydroxyl content determined by H-1-NMR was always lower than that deduced from P-31-NMR and C-13-NMR spectroscopy. (c) 2008 Wiley Periodicals, Inc.

Language: English

Type (Professor's evaluation): Scientific