Influences of elastomer and filler incorporation on impact properties for polypropylene/elastomer/filler ternary composite were investigated. Silica particles with a diameter in the range from 0.1 to 3.3μm were used and polystyrene-block-poly(ethylene-butene)-block-polystyrene triblock copolymer(SEBS) was used as elastomer. In the case that SEBS volume fraction is below 0.12,the impact strength increased gradually with a decrease of the silica particle size. In the case that SEBS volume fraction is above 0.17,the addition of silica particles with a diameter in the range from 0.1 to 2.0μm improved the impact strength. However,the addition of them with mean size of 3.3μm never improved the impact strength. The influence of silica particle size on the impact strength was similar to that of CaCO₃,particles previously reported. It was found that the inorganic particle size strongly affects on the impact strength of composite independent on the kind of particles.

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Residual stress in coating layer cause scracks and peelings.Value　of residual stress is determined by the gap of thermal expansion ratio of coating polymer and that of base material,and also by polymer's material constants such like elastic modulus.That means residual stress value can be calculated by obtaining material constants of polymer.In general,pure polymer has considerably higher value of thermal expansion ratio than that of base material. Therefore residual stress in coating layer of pure polymer tends to have higher value. Addition of inorganic filler into pure polymer is effective to obtain smaller gap between thermal expansion ratio of coating composite polymer and that of base material.But in most of the cases,composite polymer added inorganic filler came to have higher value of elastic modulus.Therefore residual stress in coating layer of composite material was not as low as expected.In this study,hollow glass microspheres were added as inorganic filler,into epoxy polymer.Composite polymer with hollow glass microspheres showed low thermal expansion with small increase of elastic modulus. As are sult,residual stress in coating layer of composite material was decreased by compounding hollow glass microspheres. Improvement on avoiding cracks and peelings were expected by this result.

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