Filled compounds of natural rubber, isobutylene-isoprene rubber
and styrene-butadiene rubber compounds were extruded through a laboratory
extruder by varying the feeding rate at different temperatures and revolutions
per minute. The extruded compounds were vulcanized up to their optimum cure
times and the mechanical properties of the vulcanizates were determined. The
properties suggest that there is a particular feeding rate in the starved fed region
which results in maximum mechanical properties. The study shows that running
the extruder at a slightly starved condition is an attractive means of improving
the physical properties.