Abstract:
Sri Lankan rubber industries process approximately 90,000 tons of natural rubber per year
for manufacture of tire tread. footwear. flooring, pneumatic tubes, rugs. dipped product and
many others. Large quantities of reinforcing and non-reinforcing fillers are required to
obtain rubber product of desirable quality. The fillers used commonly are carbon black.
silica. mica. china clay. Reinforcing fillers usually consume large amount of energy when
processed and treated, so that their cost is sharply affected by the market price increases of
energy. Mineral fillers are non-reinforcing by nature, less energy sensitive and not
susceptible to price increase. They are available and widely distributed in Sri Lanka. It was
shown in earlier research that modified mineral fillers could be used as quite economical
and versatile substitute for expensive imported reinforcing fillers. The purpose of this
paper is to establish the factors, effecting the reinforcing activity of modified fillers and
optimization of rubber -rnodified filler composite formula for industrial usage.
