Hamed Younesi-Kordkheili1,*, Antonio Pizzi2
Journal of Renewable Materials, Vol.10, No.2, pp. 237-246, 2022, DOI:10.32604/jrm.2022.017851
Abstract The aim of this research was to investigate the effect of ionic liquid treated lignin-based polyacid as a catalyst for urea-formaldehyde (UF) resins. Esterification of lignin was carried out, without any catalyst, with anhydride maleic and 1-butyl-3-methylimidazolium hydrogen sulfate [Bmim][HSO4] as acidic ionic liquid to form maleated lignin-based polyacids (MA-IL). The performance of MA-IL as UF resin catalyst was respectively compared to hyroxymethylated lignin-based polyacid (MA-HL) and to NH4Cl. The FTIR analysis indicated that the proportion of -COOH and C-O bonds increased due to the esterification of lignin with ionic liquid rather than its hyroxymethylation. Physicochemical… More >