Development of hybrid biodegradable polymer based on polyvinyl alcohol and whey protein isolate reinforced with cellulose nanocrystal from pineapple crown leaf

A hybrid biodegradable polymer film based on polyvinyl alcohol/whey protein with the addition of cellulose nanocrystals was developed by casting a homogeneous mixture containing the three components. The nano-reinforcing agent was successfully dispersed into a different ratio of polyvinyl alcohol/whey protein blend (70/30, 80/20, 90/10). The findings show that adding polyvinyl alcohol and cellulose nanocrystals into the whey protein isolate matrix improves the film's mechanical (thickness, tensile strength and elongation), physicochemical (transparency, solubility, WVP, FT-IR, XRD, and degradation), morphological (SEM) and thermal stability (TGA, DTG, Ea), which shows the higher flexibility but maintains the poor water resistance, tensile strength and compatibility with interactions in the mixed matrix. The ratio of 70/30 blend film also has better film properties and is adequate for packaging applications.