Research On The Properties Of Polylactide/ Modified Montmorillonite Nanocomposites

Poly (1actic acid) (PLA) is a very important kind of commercial biodegradable polymer with wide applications in the 21st century.However,its brittle character, lower thermal stability and bad crystalline ability restrict its further applications.Polymer blending is an efficient method to improve the performance of polymer.We used the modified montmorillonite(MMA) to improve the performance of PLA through the melting blending. The level spacing enlarged from 1.76nm to 2.01nm through the XRD, which indicated that the modifier successfully inserted the layered montmorillonite. Then, through the XRD and TEM, the level spacing of PLA/MMA changed to 3.39nm, which indicated the modified MMA scattered better than the normal MMA in PLA. And when the processing temperature fixed at 150℃and the proportion at 6%, the modified MMA scattered best.Through the DSC, 6% modified MMA could significantly increase the crystalline ability and promote the glass shift temperature. Modified MMA increased the rate of crystallization by the constant temperature DSC. The mechanical properties achieved superiorly with 6wt% MMA. Modified MMA could also promote the thermal decomposition temperature of PLA by TGA.Finally, we carried on research about the synthesis of poly(ethylene oxalate) (PEO) and poly(butene oxalate) (PBO). The experiment indicated that the melting point of PEO and PBO respectively be 178℃and 100℃. The 5% weight loss temperature promoted from 230℃to 278℃, which indicated that lengthening the carbon chain could promote the thermostability effectively.