Mechanical Properties and Molecular Transport Behavior of NR/Clay and ENR/Clay Composites

Abstract

Natural rubber and epoxidized natural rubber composites reinforced with clay have been synthesized in this study using two roll mixing mill. The effect of clay concentration on basic mechanical properties and molecular transport phenomena of the elastomeric composites was analyzed. Tensile strength and tear strength variation as a function of clay concentration were studied. It was found that as clay concentration increased up to 4 phr, tensile strength improved up to 22.5MPa and tear strength up to 32 MPa, beyond which it went down. It was also found that corresponding to 4 phr clay concentrations, the crosslink density of the composite was at a maximum of 1.45gmol/cc. As the clay contents are added into the elastomeric matrix system, initially there is a decrease in the swelling coefficient, but later at higher loading, the swelling coefficient increases due to the agglomeration of clay particles in the matrix.