Bioplastic from empty fruit bunch cellulose/chitosan/starch: Optimization through box-Behnken design to enhance the mechanical properties

Abstract

This investigation was centered on the intricate processes of fabricating and fine–tuning the concentration of microcellulose derived from oil palm empty fruit bunch (OPEFB). The objective was to employ it as a reinforcing agent, with sorbitol serving as a plasticizer, and chitosan acting as both a plasticizer and a strengthening agent for the formulation of bioplastic films to gain higher value mechanically. The cellulose extraction involved a methodical delignification approach, extracting lignin and hemicellulose from OPEFB to yield brown pulp. Subsequent double peroxide bleaching was employed to reduce the lignin concentration in the pulp. Leveraging the Box–Behnken experimental within a response surface methodology framework, the study scrutinized the influence of independent parameters (additive concentrations) on the ultimate tensile strength and Young’s modulus of the fabricated bioplastic films. Noteworthy variations in ultimate tensile strength and Young’s modulus were discerned, underscoring the impact of microparticle loading on the mechanical attributes of the bioplastic films. The quadratic polynomial model derived from experimental data exhibited coefficients of determination (R2) of 0.8690 for ultimate tensile strength and 0.6793 for Young’s modulus, affirming the adeptness of the models in navigating the optimization space. Microcellulose was isolated (30 – 40) wt.% of OPEFB as the white pulp which revealed a homogenous dispersion with chitosan in the corn starch matrix. The superior tensile strength and Young’s modulus were observed at 6.84 MPa and 21.94 MPa respectively.