Packaging Film of PP/LDPE/PLA/Clay Composite: Physical, Barrier and Degradable Properties

摘要

This work sought to improve the properties of polypropylene (PP) for single layer film application by incorporating low density polyethylene (LDPE), poly(lactic acid) (PLA) and montmorillonite (MMT). The addition of LDPE in PP improved the elongation at break and tear strength. The PP/LDPE blend at a 80:20 (w/w) ratio was selected for blending with PLA and MMT and the PP/LDPE/PLA/MMT composite showed an increased tensile modulus, while the elongation at break decreased, with increasing PLA and MMT contents. The morphological structure of the respective nanocomposites was examined using X-ray diffraction, transmission electron microscopy and scanning electron microscopy analyses. For the barrier properties, the incorporation of PLA and MMT in PP/LDPE blend tended to dramatically decrease the oxygen permeability but slightly increase the water vapor permeability. Moreover, the PP/LDPE/PLA/MMT composite as a new effective film decreased the tomato loss weight during low temperature storage (15-20 degrees C) compared to the PP film.