MECHANICAL PROPERTIES OF CHITOSAN MODIFIED MONTMORILLONITE FILLED TAPIOCA STARCH NANOCOMPOSITE FILMS

摘要

This study was carried out to develop renewable and degradable plastics film with good mechanical properties. The mechanical properties between compatibilized montmorillonite (MMT)/chitosan filled tapioca starch (TPS), uncompatibilized MMT/TPS, and chitosan/TPS nanocomposite films were investigated. Experimental works were started with the extraction of local chitosan from chitin derived from prawn shells which involving deprotenization, demineralization and deacetylation treatments. Degree of deacetylation of chitosan was determined using infrared spectroscopy method. Chitosan was acted as compatibilizer between MMT and starch in order to improve the dispersion of MMT in nanocomposite systems. Nanocomposite films were prepared using a solution casting method with addition of glycerol as the plasticizer. The starch solution was cast onto PTFE mold with cavity thickness of 0.5mm. Characterizations of the nanocomposite films were done using Fourier Transform Infrared Analysis (FTIR). Tensile properties of nanocomposites were investigated. The compatibilized nanocomposite films, chitosan/MMT/TPS give significant effects to tensile properties. Chitosan has played its role as the compatibilizer and also as flexibility improvers to nanocomposite films because elongation at break improved after addition of chitosan.