PHYSICOCHEMICAL AND ANTIBACTERIAL PROPERTIES OF PLA-CHITOSAN BLENDS OBTAINED BY CASTING WITH POTENTIAL USE AS AGRICULTURAL MULCH FILMS

Abstract

PLA-Chitosan films compatibilized with hexamethylenediisocyanate (HDI) were obtained by casting and subsequent hot pressing. The films were prepared with different contents of chitosan (CS) and then its physicochemical properties were studied by Fourier Transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), optical microscopy (OM) and X-ray diffraction (XRD). It was found that the compatibilizing agent reacts completely and that chitosan affects the thermal properties of the films decreasing their decomposition temperatures, glass transition temperature (Tg) and melting (Tm) and increase its crystallinity. From the functional standpoint, antimicrobial properties of each blend were tested against Pseudomonas syringae pv tomato DC-3000. The increase in chitosan content was proportional to the antimicrobial effect allowing project its potential application in the agronomic field.

Keywords

• Biodegradable films
• polymer blends
• casting
• mulch