Effect of OPEFB-NCC Axial Ratio on Optical Properties of NCC Film

Abstract

Abstract-In this study, we report the effect of axial ratio on the properties of films from OPEFB-NCC. OPEFB-NCC is prepared via the TEMPO oxidation process whilst NCC's with different axial ratio (designated as LAR-NCC, MAR-NCC and HAR-NCC for short, medium and long fibrils respectively) are produced using the centrifugation and filtration technique. OPEFB-NCC films are prepared using the standard film casting method. SEM micrographs show that the surface morphology of all types of films appear to be smooth and homogenous with multilayered deposition of particles, whereas the cross section morphology shows the presence of voids in the HAR-NCC film but almost none were visible in the MAR-NCC and LAR-NCC films. MAR-NCC and LAR-NCC films are visually transparent whilst the HAR-NCC films are opaque in nature which is in agreement with the light transmittance measurement where higher transmittances were observed in the LAR-NCC film as compared to MAR-NCC and HAR-NCC film in the visible wavelength section. Thermal analyses show that there are no significant differences in thermal stability even though the axial ratios of samples are different. Index Terms-Axial ratio, OPEFB-NCC, OPEFB-NCCfilm, SEM, optical properties.