The Effect of Silica Filler and Aging on Breakdown Voltage and Some Mechanical Properties of Styrene-Butadiene Rubber(SBR)/Silica

The effect of silica filler percent on breakdown voltage(VBD) and some mechanical properties (Tensile strength (T.S),Ultimate elongation (E%)and Equilibrium swelling (Q%)) of StyreneButadiene rubber filled with (20,40,60,80,100) phr (part per hundred rubber) of silica have been investigated. It was found that breakdown voltage and tensile strength were increased, while ultimate elongation and equilibrium swelling were decreased with increasing of silica filler percent. The effect of thermal aging on these properties was investigated. It was found that breakdown voltage, equilibrium swelling and ultimate elongation were slightly decreased while tensile strength was increased with aging time. The largest effect during aging appeared on samples with smaller filler loading. The same tests have been done for all samples after2 years (i.e Natural aging). It was found that breakdown voltage, ultimate elongation and tensile strength were slightly decreased while equilibrium swelling was increased compared to thermal aging results, although that the effect of both agings is the same on each property for samples with different silica filler percents.