Structure and properties of PP/CaSO4 composite - Part III: Effect of the filler grade on properties

The mechanical properties viz.impact strength and tensile modulus of polypr opylene (PP) containing two different types of calcium sulphate (prepared b y in situ method under controlled conditions in a polymer matrix i.e. polye thylene oxide in the composition range 0-25 wt% of filler were studied. Inc rease of impact strength together with high crystallinity and improved tens ile modulus was observed in one of the grades of CaSO4 filled composite as compared to pure PP. This could be associated with the long needle shaped C aSO4 crystals and the change in the structure and morphology induced by the same in the PP matrix. (C) 2000 Kluwer Academic Publishers.