Thermal Properties, Crystallinity, and Oxygen Permeability of Na-montmorillonite Reinforced Plasticized Poly(lactic acid) Film

摘要

Introducing unmodified organically clay/Na-montmorillonite (Na-MMT) was applied into plasticized poly(lactic acid)?PLA ?to ?produce ?film ?composites ?by direct ?casting. ?Film ?composite ?structure, ?the ?crystallinity ?degree ?and ?form, and?thermal ?properties ?were ?carried ?out ?using ?X-ray ?diffraction ?and differential ?scanning ?calorimetry. ?The effect ?of NaMMT ?to ?the ?tortuous path ?and ?the ?crystallinity ?degree ?in ?the ?plasticized ?film ?composites ?were calculated ?in oxygen?barrier ?properties. ?Chromatogram ?film ?composites resulted ?in ?an ?intercalated ?structure ?that ?showed ?peak diffraction?angle shift at about 0.2o. Then, a peak diffraction pattern was indicated in ?α-form crystal structure. Plasticized PLA has?a crystallinity degree at 34%, and the addition of ?Na-MMT increased to 52%. Glass transition temperature improved?from 53 °C to 57 °C, and melting temperature remained stable at 167 °C. Filling Na-MMT into plasticized PLA caused?to enhance a tortuous path about 28% and improved the oxygen permeability to 80%. As a result, the addition of NaMMT of 3% into plasticized PLA during ?film composite preparation using the mixing method resulted in balancing?properties related to the crystallinity degree, thermal properties, and oxygen barrier properties.