Synthesis Of Polymer Chain Extender And Application In Polylactic Acid

Poly methyl methacrylate-co-glycidyl methacrylate(PMMA-GMA), epoxy-type chain extender, was synthesized by bulk polymerization. Chain extension of polylactide (PLA) using chain extenders in melt process was studied. When the epoxy groups GMA content of was different, there was different chain extender effect for polylactide. The polymer was characterized using gel permeation chromatography, differential scanning calorimetry and Thermogravimetric analysis.Pure materials of Polylactide and PMMA-GMA were studied. PLA resin did not appear thermal degradation below 220℃, PLA resin appeared thermal degradation when the temperature was 240℃, the content of GMA had little change for the glass transition temperature, molecular weight, rheological properties of chain extender.When the epoxy groups GMA content of epoxy -type chain extender was 4%, the results showed that:With increasing the content of chain extender, the value of balance torque was greater, the molecular weight was greater, Cold crystallization temperature and melting temperature were affected. The thermal stability is improved, but did not change significantly.When the epoxy groups GMA content of epoxy -type chain extender were 2%,8% and 12%, the results showed that:the change regular of the value of balance torque,the molecular weight,thermal properties and thermal stability was similar. It can cause cross-linking by excessive the content of GMA and PMMA-GMA.Chain extender was synthesized by emulsion polymerization, Chain extension of PLA using chain extenders in melt process was studied. The polymer was characterized using gel permeation chromatography. The results showed that:the change of Molecular Weight is irregular. This shows that the effect of chain extension by bulk polymerization is better.