Effects of ultrasonication-assisted homogenization on morphology and properties of thermoplastic starch/cellulose biocomposites

Abstract

The thermoplastic starch/cellulose biocomposites were manufactured as green biocomposite films. TPS was produced through plasticization which the mixture of granule starch, water and glycerine went through the heating process, while the suspension cellulose was prepared through the ultrasonication process involving isolation of cellulose in water using ultrasonic probe. The ultrasonicated cellulose suspension was reinforced into TPS to produces TPS/cellulose biocomposites by film casting. In order to study the effect of ultrasonication period of fiber on the composite properties, the morphology and mechanical properties of films were investigated. The composite materials were compatibilized to each other as hydroxyl group found in Fourier Transform Infrared Spectroscopy (FTIR) pattern. In X-ray Diffraction (XRD) testing, the crystallinity of cellulose and biocomposite were altered by the induced of ultrasonication. The uniform dispersion of the fibers was investigated using Scanning Electron Microscope (SEM) images. The tear and tensile strength of TPS biocomposites were satisfactorily enhanced by increased of ultrasonication duration compared to the pure thermoplastic starch film. The longer period of ultrasonication to cellulose, the better properties of TPS/cellulose biocomposites could obtain.