Simulation and experimental characterizations of polyvinyl alcohol-cassava starch compound for injection moulding application

Abstract

Polyvinyl alcohol (PVOH) blends with cassava starch (CSS) is a biodegradable polymer compound. This polymer compound is suitable to be used as biodegradable material to reduce the accumulation of synthetic petroleum-based polymer solid wastes. In this study, the fundamental blending characterizations of PVOH-CSS were investigated by molecular modeling to unveil the hydrogen bonding interactions among the blending components. In addition, infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) were conducted to support the molecular modeling outcomes. The processability behaviour of the PVOH-glycerol-CSS compounds (PGCS) such as specific heat capacity, pressure-volume-temperature, and shear rate-viscosity were studied as well. These data were imported into Moldflow software for injection moulding simulation based on a name tag article design (NTA). Subsequently, the simulated outcomes were validated by actual injection moulding process using statistical analysis. The fundamental blending characterizations results showed that blending of PVOH and CSS are synergistically compatible. However, the incorporation of glycerol has weakened the genuine interactions between PVOH and CSS. Meanwhile, the processability study of PGCS showed that 40 wt.% and 50 wt.% CSS compounds are favourable to be injection moulded. Finally, the statistical outcomes have concluded that optimum processing can help to produce NTA with low volumetric shrinkages at acceptable variabilities. In conclusion, PVOH-CSS blend is a compatible polymer compound. It is also a high potential injection moulding processable biodegradable starch-based polymer compound.