Packaging and degradability properties of polyvinyl alcohol/gelatin nanocomposite films filled water hyacinth cellulose nanocrystals

Abstract

Cellulose nanocrystals isolated from water hyacinth fiber (WHF) have been studied as a reinforcement for polyvinyl alcohol (PVA)-gelatin nanocomposite. Central composite design was used to study and optimize effects of the PVA, gelatin and cellulose nanocrystal (CNC) concentration on tensile strength and elongation of formed films. The results of this study showed that WHF CNC had a diameter range of 20–50 nm produced films reaching 13.8 MPa tensile strength. Thermal stability of the films was improved from 380 °C to 385 °C in addition of CNCs and maximum storage modulus of 3 GPa were observed when 5 wt% CNC was incorporated. However, water absorption, water vapour permeability (WVP) and moisture uptake of the films decreased in addition of CNC to the PVA-gelatin blends. Moisture uptake decreased from 22.50% to 19.05% while the least WVP when 10 wt% CNC added was 1.64 × 10–6 g/(m•h•Pa). These results show possibility for industrial application of WHF CNC and PVA-gelatin blends in biodegradable films for on-the-go food wrappers.

Keywords

• WATER hyacinth
• Polyvinyl alcohol
• Gelatin
• Cellulose nanocrystals
• Central composite design
• Packaging films