THERMAL-DEGRADATION OF POLYCHLOROPRENE RUBBER

Accelerated thermal ageing of polychloroprene rubber was studied by measuring the residual deformation under constant deflection in air. The results obtained were processed using the Arrhenius model for the change in reaction rate with temperature. It was found that the apparent activation energy of the ageing process depends up on the degree of thermal degradation. There was also found to be a linear relationship between ln A and activation energy (ageing compensation effect). Thermal analysis (TG, DTG, DTA) of polychloroprene rubber was carried out at various heating rates to determine the apparent activation energy changes for the thermal oxidative degradation under non-isothermal conditions as a function of the degree of transformation. The thermal analysis results were correlated with those obtained in studying the change of the residual deformation under constant deflection, so that mechanical ageing of polychloroprene rubber may be correlated with the formation of volatile products on heating this material.