Effect of ZnO nanoparticles on the tensile strength of the thermoplastic cationic starch/montmorillonite biodegradable films

One of the polymer technologies that can be used to reinforce the physical and mechanical properties, is polymer/nanoparticle composite development. Because of the nanometer-sized particles that diffuse in the matrix of starch, the composites of TPS/nanofiller demonstrates good improvements in gas barrier, tensile strength, thermal properties, etc. [1]. In this study, various amounts of nanoclay montmorillonite (MMT) and ZnO nanopowders were used to analyze the tensile strength of the biodegradable nanocomposites of cationic starch (CS). Nanocomposites are produced by solvent casting method. The Tensile strength (TS) of the nanocomposites were specified at 21±1 °C based on ASTM D882-10 (ASTM, 2010) by using a tensile tester (Zwick/Roell model FR010, Germany). Three nanocomposite samples which were conditioned in RH= 55% for 48 h and then were in 6 cm×0.5 cm dumbbell form, were cut from nanocomposite samples and were placed between the machine grips. The cross-head speed and primary grip separation were set to 50 mm and 5 mm/min, respectively. Results showed that the Tensile strength (TS) of nanocomposites increased after the incorporation of ZnO and MMT nanoparticles although the elongation at break was diminished. It was also concluded that the 3 and 0.7 wt% amounts of montmorillonite and ZnO nanoparticles were sufficient in order to acquire a well-moderated mechanical behavior in plastic and elastic regions, and they also cause good improvements in barrier and optical properties.

کلیدواژه ها:

Cationic starch ، ZnO ، Montmorillonite ، Mechanical properties ، Biodegradabale ، bionanocomposites.