Preparation and Characterization of PLLA/OMMT-MAH Nanocomposite by Esterification Method

In this study, in order to avoid the serious degradation of poly (L-lactic acid) (PLLA) caused by maleic anhydride (MAH) while taking advantages of its interfacial compatibility, an esterification between OMMT and MAH was designed to form OMMT-MAH composite. The experiments showed that the esterification rate of OMMT (100 degrees C, without oxygen and using cyclohexanone as a solvent) is 6.5 %. Compared with pure PLA, PLA/OMMT-MAH (OMMT-MAH 1 wt%) obtained an optimum performance except impacting strength. And the crystallinity increased from 6.36 to 9.49 %. Compared with composites without initiator, the mechanical properties of composites with initiator improved slightly except bending modulus, which indicated that double bond on OMMT-MAH was opened under the effect of dicumyl peroxide (DCP) and connected with PLLA main chain by bonding. In this study, a novel method to modify MMT was found, and it was an effective way to improve the performance of PLLA.