The effects of esterification with stearic acid on the crystallizing behavior,thermal stability and resistance to water of polyvinyl alcohol(PVA) were studied by using IR, WAXD, DSC, TG and water resistance test.The results show that the esterification of PVA with stearic acid could take place in the presence of dibutyltin dilaurate at 128℃.—OOC(CH\-2) 16 CH 3 groups are introduced into PVA molecular chains during esterification.With increasing the reaction time, the thermal stability and water resistance of PVA are improved.However, the crystallinity and melting temperature of PVA are decreased. As reaction time exceeds 16h,the crystalline structure of PVA disappears according to WAXD and DSC curves.The initial decomposition temperature after esterification is over 200℃,much higher than that of PVA.These results suggest a method for improving the thermal stability and water resistance of PVA.
