Study on the Influencing Factors in the Tensile Property Test of PP and PS

The effects of the different tensile rate and methods for preparing samples on polypropylene (PP) and polystyrene (PS) tensile strength and elongation at break were studied.The result showed that tensile strength of PP and PS increased with the tensile rate increasing.But the elongation of two materials presented different changes.The tensile strength and elongation at break of injection molding samples of PS were much higher than the compression molding samples of PS.The elongation at break of injection molding samples of PP increased 69% than the compression molding samples.But tensile strength did not change obviously.The samples were strong and tough.