Mechanical Properties of Highly Filled Elastomers VII. The Shear Modulus of Rubbers Containing Fillers with a Bimodal Size Distribution

摘要

A polyurethane rubber was filled with a mixture of coarse and fine sodium chloride particles. The size of the coarse particles was about 250 m, that of the fine particles about 35 m. The mixing ratio of coarse to fine particles was varied systematically. The total content of filler ranged from 0 to 70 per cent by volume. For these materials, the shear modulus was determined in the rubbery state, i.e. far above the glass-rubber transition temperature. The modulus depended on the total content of filler as well as on the mixing ratio of coarse to fine. A theoretical explanation could be given. (Author)