HOMOGENEOUS PHTHALATION OF EUCALYPTUS IN DIMETHYL SULFOXIDE/N-METHYLIMIDAZOLE AT ROOM TEMPERATURE

摘要

A novel route to homogeneous modification of wood at room temperature is developed in present study. Phthalation of ball-milled eucalyptus with phthalic anhydride using DMSO/NMI as reaction media at room temperature without any catalyst were investigated. The effects of parameters including the dosage of phthalic anhydride and reaction time on phthalation, which was measured by Weight Percent Gain (WPG), were studied. The results showed that 0.5-5 times of phthalic anhydride based on the eucalyptus weight led to the corresponding increase in WPG from 39.5% to 192.1%. However, the increment of reaction time (from 1 h to 5 h) had little effect on the yield of products, and WPG was almost not changed. The phthalated cell wall derivatives were also characterized with FT-IR and solid-state CP/MAS 13CNMR spectroscopies. The results indicated that the reaction of hydroxyl groups at C-6, C-2 and C-3 positions in cellulose occurred. The lignin and noncellulosic polysaccharides were also phthalated. The thermal stability of the phthalated eucalyptus was found to decrease upon chemical modification.