Effect of Surface Treated Biopolymer on Curing Behavior and Tensile Properties of Natural Rubber Composites

The growing demand for environmentally friendly materials has prompted several researchers to explore naturally occurring biopolymers for potential applications in a variety of fields. Cellulose is a biopolymer formed by the repeated joining of D-glucose building blocks and is characterized by its hydrophilicity, broad chemical modification capacity, biodegradability, and the formation of versatile morphologies of semicrystalline fibers; However, the interactions between the cellulose and the polymer matrix are limited due to the fact that the cellulose is hydrophilic while the matrix is hydrophobic. The surfaces are thus not sufficiently compatible, leading to a reduction in mechanical properties. In this study, cellulose was surface treated with two types of silanes. Modified cellulose was used as filler in natural rubber composites. The influence of treated and untreated cellulose on the curing characteristics, rheological properties, mechanical properties and crosslinking density of natural rubber composites was examined. The curing characteristics of the natural rubber composites, the scorch time and cure times, decreased for natural rubber composites filled with modified cellulose compared with natural rubber composite filled with unmodified cellulose. The measured values of tensile strength and crosslinking density showed higher values for natural rubber composites filled with modified cellulose compared with natural rubber composite filled with unmodified cellulose.