加硫ゴム中におけるゴム : 充填剤の相互作用

Abstract

The stress-strain relation of filler lorded rubber vulcanizates was studied by use equations of (1) and (2). [numerical formula] Good applicability of eq. (1) for unfilled and non-active filler filled vulcanizates was comfirmed, but the deviation appeared at large deformation for carbon black filled one. Moreover, unfilled and non-active filler filled vulcanizates give a simple exponential curve in f/F(α)-α plot which may be estimated the effect of addition force, whereas the carbon black filled ones give curves having a steep increase at large deformation. In the filled vulcanizates, the actual elastic force involes various effects, such as the volume effct, the secondary force arising from a rubber-rubber interaction and a rubber-filler one. The volume effect can be eliminated by using a modified elongation α'. The rubber-rubber interaction can be evaluated from the pseudo-crosslink theory as unfilled rubber. It is assumed that rubber-rubber interaction consists of the pseudo-crosslinks formation between rubber and filler and orientation of chain due to increased tension of rubber molecule. It was recognized experimentally that these factors are proportional to the volume of filler or the total surface area of filler and the elongation ratio.