Synthesis and thermal properties of epoxy resins from ester-carboxylic acid derivative of alcoholysis lignin

摘要: Alcoholysis lignin (AL) was dissolved in ethylene glycol and the obtained mixture reacted with succinic anhydride to form a of ester-carboxylic acid derivatives (AL-polyacid, ALPA). Ethylene glycol-polyacid (EGPA) also prepared from glycol. The ester carboxylic treated diglycidyl ether presence catalytic amount dimethylbenzylamine ester-epoxy resins. curing reaction analyzed by Ozawa's method using differential scanning calorimetry. activation energy initial step found be ca. 84 kJ mol -1 . molar ratios epoxy groups ([EPOXY]/[AA] ratios) were varied 0.8 1.3. contents ALPA EGPA 0 100 %. Thermal properties resins studied DSC thermogravimetry. Glass transition temperatures showed maximum value -11.5 °C when [EPOXY]/[AA] ratio 1.1. Tg increased increasing suggesting that acts as hard segment resin networks. degradation slightly decreased contents.