Study on modification of polylactide by functional polymer

Poly methyl methacrylate-co-glycidyl methacrylate copolymers (PMMA-GMA) was synthesized by bulk polymerization. The copolymers were blended with polylactide (PLA) in Haake rheometer at different weight ratio from 0% to 15% as chain extender and modifier. The properties of neat polylactide(PLA) and modified PLA were characterized using gel permeation chromatography, differential scanning calorimetry, and Thermogravimetric analysis. The results showed that: PMMA-GMA is an effective chain extender for PLA. The balanced torque and temperature of PLA increased with the increasing of copolymer chain extender content. PLA seemed to be corsslinked when the content of copolymer reached 15%. The number everage moleculer weight and the weight everage moleculer weitht of PLA increased simultaneously. The glass transation temperature of PLA was pushed to higher temperature by the introduction of copolymer. The introduction of copolymer affected the cold crystallization behavior and melting behavior of PLA. The thermal stability of PLA was improved slightly by the introduction of copolymer.