Preparation and characterization of polystyrene and thermoplastic starch blends

Abstract

The characterization of PS blending TPS was conducted under several measurements such as tensile testing, scanning electron microscopy (SEM), Thermogravimetric Analysis (TGA) and Fourier-Transform Infrared Spectroscopy (FTIR) and water absorption. The preparation of TPS/PS blends was divided into three stages. The first stage involved the preparation of TPS from starch. The preparation of TPS was conducted by using heated two roll mill at temperature 150°C for 10 minutes. Then, for the second stage, PS was blended with TPS to produce TPS/PS blend. Several ratio of TPS/PS blend are divided to 20:80, 40:60, 60:40, and 80:20. Last stage is modification of the composition of TPS/PS blends with succinic anhydride and ascorbic acid treatment. Both untreated and treated blends was characterized their physical, thermal and surface morphology properties. The result indicate that treatment TPS/PS have better tensile strength as treatment increase adhesion between TPS and PS component. However, increase TPS loading in the blends decreased the strength as TPS give no strength to the blends. Furthermore, based on the SEM micrograph, treated ascorbic acid and succinic anhydride performed better interfacial phase as compared to untreated TPS. The micrograph was found there is no agglomeration and voids formation occurred in TPS/PS blending. Better thermal stability was proved for the treated blends due to have higher degradation temperature. Water uptake into the TPS/PS blends also decrease after the treatment and the FTIR result show the formation of new peak after the treatment process