Preparation and Application of Lignin-Based Epoxy Resin from Pulping Black Liquor

摘要

abstract_textpIn the present work, lignin was isolated from pulping black liquor. Selective precipitation was achieved by adding hydrochloricacid to adjust pulping black liquor pH from 1 to 5. Reaction pH, reaction temperature and the content of lignin were investigated in the total process. A considerable increase in the amount of precipitate was observed while pH was decreasing. Lignin obtained from pulping black liquor had been used as the reactant to partly replace bisphenol A in preparing epoxy resins with different lignin additives at 90 degrees C. The mechanical and the thermal properties of cured lignin-based epoxy resins were compared with those at different contents of lignin and reaction temperatures with ethylenediamine as the curing agent. The cured lignin-based epoxy resins with 20 wt. % lignin at 90 degrees C showed the highest viscosity up to 396 MPa.s. We had successfully got good performance lignin-based epoxy resin./p/abstract_text