Preparation and characterization of cellulose nanocrystalline reinforced polyvinyl alcohol

Abstract

This project studies the preparation and characterization of cellulose nanocrystalline (CNC) reinforced polyvinyl alcohol (PVOH). The mechanical properties, chemical composition, morphological surface and the water absorption of the composite film were studied. Different concentrations of CNC, from 0 wt% to 5 wt%, were added in to PVOH. The Young’s Modulus increased as the percentage in weight of CNC increased while tensile strength and elongation at break decreased. Tensile strength decreases up to 43.9% when 5 wt% of CNC is added in to PVOH. The citric acid (CA) was added as a crosslink agent. Thus, the tensile strength and elongation at break were improved by the addition of CA. With the presence of CA, tensile strength improves in the range of 8% to 41% compare to the composite film without CA. It is proven by the Scanning Electron Microscope (SEM) micrograph of the composite films. The morphological surface of crosslinked composite film show smoother surface as compared to non-crosslinked composite film. Based on the water absorption test, the linkage between CA and PVOH resulted in the reduction of water absorption ability. Therefore, the percentages of weight change for composite films without CA were lower than the composite films with CA. This study shows that with the presence of CNC, the properties of the composite film formed are improved and CA act as the crosslink agent is able to enhance the properties of the composite films as well.