Extraction and characterization of cellulose nanocrystals derived from wood sawdust for bioplastic production

Abstract

This research study develops a sustainable approach to convert wood sawdust (WSD) from Cordia africana, found from in Bahir Dar, Ethiopia, in to cellulose nanocrystals (CNC) and CNC reinforced bioplastics (SDB). CNC was extracted through sequential alkaline treatment, bleaching and sulfuric acid hydrolysis, resulting in a consistent yield of about 35.6%. The extracted material exhibited high cellulose purity and low contents of non cellulosic components and moisture content was significantly reduced compared to raw sawdust. Bioplastics were fabricated by incorporating CNC into polyvinyl alcohol (PVA) with glycerol as a plasticizer. FTIR, SEM, and EDX confirmed removal of non-cellulosic components and strong interactions between CNC and polymer matrix were occurred in the bioplastic structure. Thermal analysis showed that CNC reinforcement improved thermal resistance. Therefore, in the current study, potential of WSD to produce biobased materials with tunable properties is highlighted in the valorization of wood sawdust as a renewable cellulosic resource, which in other word implied, context specific solution for sustainable waste management, circular bioeconomy and reduction of fossil based plastics in developing country like, Ethiopia.