Effects of Deformation History on Viscoelasticity of Filled Rubber Compounds

Effects of deformation history and surface activity of carbon black on viscoelastic behavior of carbon black filled rubbers were investigated. Storage modulus (G') decreased by the repeated strain sweeps in the strain region of γ=0.001∼0.4. The change in G' depends on maximum strain, γ max. As the γ max increases, the G' in the small strain region drops. The samples showed recovery in G' by being kept at a given temperature. The degree of recovery in G' was found to depend on the temperature and the surface activity of carbon black. The degree of recovery in G' for graphitized carbon black filled compound which has weak interaction between polymer and filler, is higher compared to the nongraphitized one. The recovery behavior in G' for graphiitzed carbon black was found to be due to viscosity of rubber for matrix.