Evaluation of mechanical properties of polypropylene filled with wollastonite and silicon rubber

Some novel composites were prepared with polypropylene and silicon rubber with wollastonite as fibrous filler having aspect ratio 5:1 in different proportions. Subsequently, these composites were investigated for tensile, impact (notched and unnotched), flexural strength, flexural modulus and heat deflection temperature (HDT). A special interest has been devoted to the measurement of flexural modulus and heat deflection temperature since this is an important property in many applications. The results show that there is a marginal change in mechanical properties of the untreated wollastonite-filled polypropylene composite on addition of silicon rubber and malicanhydride, whereas the enhancement in the HDT was significant. In specific, an addition of 5% rubber in the polypropylene composites having wollastonite at different compositions of 10%, 20%, 30% and 40% provided, in general, enhanced HDT, notched impact strength and flexural strength, but, reduced unnotched impact strength, tensile strength and flexural modulus.