Based on a simplification of physical model

the change of conductivity was studied by using the ratio of real current to theoretical current during the stretching of conductive rubber

and the relevant measurement was set up. The composite of polyaniline (PAn) and SBS was prepared by in situ emulsion polymerization technique

which can be processed by melt method (MP) or solution method(SP). The SSP sample was made by the treatment of SP sample with m cresol. The change of conductivity was measured during the stretching of the composites

of which the PAn content is 11. 0%(wt).The results show that;(A) the conducyivity of MP sample markedly increased with elongation

for example

the conductivity increased about 15.6 times at the elongation(k) of 450%;(B) the conductivity of SP sample increased to 5.2 times at k equal to 500%;(C) For SSP sample the change of conductivity was relatively small

1k/σo)k/σo=1+k/(a+bk2) was suggested to express the regularity.The result may be caused by a tenuous interconnected network of conductive component which was induced by secondant doping with m-cresol.