Influence of Composition on Mechanical Properties of Cassava Starch, Sisal Fiber and Carnauba Wax Biocomposites

Abstract

Concern for sustainable development has provided significant improvements in the development of biodegradable materials. This work aims to evaluate, through a central composite design (CCD), the mechanical properties of cassava starch-based biocomposites manufactured with different compositions of carnauba wax (CW), sisal fiber (SF) and glycerol (G). The biocomposites were obtained by casting method. The tensile strength (TS), modulus of elasticity (ME) and elongation at break (El) for the biocomposites were determined by tensile tests. Representative models were obtained to explain changes in mechanical properties of biocomposites as function of composition variables. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were employed to elucidate interactions between the starch matrix and additives A biocomposite with 7.5% sisal fiber, 10% carnauba wax and 10% glycerol showed the best properties to possible applications.

Keywords

• biodegradable material
• composite central design
• crystallinity
• X-ray diffraction