EFFECTS OF THE ADDITION OF POLY (VINYL ALCOHOL) ON THE PROPERTIES OF NANOFIBRILLATED CELLULOSE FILMS

Abstract

In this study, based on the mechanical shear treatment, the cellulosic pulp was defibrillated in nanofibrils dispersed in aqueous suspension. Nanofibrillated Cellulose (NFC) - Polyvinyl Alcohol (PVA) nanocomposite films were prepared by the casting method from the addition of PVA to the NFC suspensions. The morphology, thermal and mechanical properties of the films were evaluated. PVA at low levels (2, 5 and 10 wt%) was used as an additive in a nanofibrillated cellulose matrix (NFC), proposing the predominant use of NFC with properties superior to its pure, through an efficient and environmentally friendly method of producing NFC based biodegradable materials with improved properties for high level applications. The addition of PVA to the NFC yields extremely positive results, because it causes little interference in aesthetic terms, but with a great gain of mechanical resistance, 24% increase in modulus with the addition of 10% PVA. It does not change in a relevant way the chemical composition of the samples in relation to the NFC. It decreases the hydrophilicity of the film's surface in relation to the film containing only NFC. It does not show major changes in the brightness of the film surface. It does not change the temperatures of thermal degradation, showing that even though it is not very resistant to temperature, in the proportions used, NFC preserves its thermal resistance.