Color and Gloss Changes of a Lignin-Based Polyurethane Coating under Accelerated WeatheringShow others and affiliations
2024 (English)In: Journal of Renewable Materials, ISSN 2164-6325, E-ISSN 2164-6341, Vol. 12, no 2, p. 305-323Article in journal (Refereed) Published
Abstract [en]
The purpose of this research study was to investigate the properties of polyurethane coatings based on ligninnano-particles. For this purpose, the prepared coatings were applied to pine wood surfaces and weathered artificially.Subsequently, color and gloss of the coatings were measured before and after the weathering test. Fieldemission scanning electron microscopy (FE-SEM) micrographs prepared from the coatings showed that the averagesize of nano-particles in the polyurethane substrate was approximately 500 nm. Nuclear magnetic resonance(13C-NMR) spectroscopy showed that strong urethane bonds were formed in the nano-lignin-based polyurethane.Differential calorimetric analysis (DSC) test revealed that the glass-transition temperature (Tg) of lignin nanoparticlesmodified with diethylenetriamine (DETA) was 112.8°C and Tg of lignin nano-particles modified withethylenediamine (EDA) was 102.5°C, which is lower than the Tg of un-modified lignin (114.6°C) and lignin modifiedwith DETA (126.8°C) and lignin modified with EDA (131.3°C). The coatings modified with lignin nano-particleshad a greater change in gloss. The lignin nano-particles in the modified coating are trapping hydroxylradicals which reduces photoactivity and yellowing of the polyurethane by about 3 times compared to unmodifiedpolyurethane coatings. After weathering test, the nano-lignin-based coating had a rougher surface with a lowercontact angle (0.78°) compared to the unmodified polyurethane coating (0.85°).
Place, publisher, year, edition, pages
Tech Science Press , 2024. Vol. 12, no 2, p. 305-323
Keywords [en]
Amination, propylene carbonate, lignin, biopolymer, polyurethane, coating, polyol, UN SDG 13
National Category
Wood Science
Research subject
Wood Science and Engineering
Identifiers
URN: urn:nbn:se:ltu:diva-104538DOI: 10.32604/jrm.2023.043953Scopus ID: 2-s2.0-85187147544OAI: oai:DiVA.org:ltu-104538DiVA, id: diva2:1843340
Note
Godkänd;2024;Nivå 0;2024-04-08 (marisr);
Full text license: CC BY;
Funder: Tarbiat Modares University of Tehran
2024-03-082024-03-082024-12-06Bibliographically approved