Effects of Higher Non-Black Filler Loadings on the Mechanical Properties of Ethylene Propylene Diene Monomer-Natural Rubber Blends

Abstract

Blends of natural rubber and ethylene propylene diene monomer rubber in three blend ratios were prepared and the variation in mechanical properties was investigated with different nonblack fillers at different loadings. The fillers used were clay and silica in the ratio 50, 100, 200 and 20, 10, 10 parts per hundred parts of rubber respectively. Among the three blends the one with 75 weight % of natural rubber gave better tensile properties. The increased filler loadings lowered the tensile strength in all blend ratios. The hardness in general was increased with increased filler loadings in all blends and was recorded maximum for blend with 75 weight % of natural rubber. The thermal ageing studies revealed that the thermal stability increased considerably with increased weight % of ethylene propylene diene monomer rubber. The enhanced thermal stability is evidenced from the tensile strength and elongation at break measurements before and after ageing.