Investigation on the Coordination Interfacial Reaction by Dynamical Mechanical Analysis

Abstract

Cross‐linking behavior of acrylonitrile butadiene rubber (NBR)/copper sulfate (CuSO4) and NBR/cobalt dichloride (CoCl2) composites were investigated by dynamic mechanical analysis (DMA) under nonisothermal and isothermal modes. In the nonisothermal test, a comparison among the NBR/CuSO4, NBR/CoCl2 and NBR/sulfur revealed that coordination cross‐linking of CuSO4‐NBR and CoCl2‐NBR happened. The isothermal test helped in further understanding of the two reaction processes in the coordination cross‐linking system through analysis of the differential curves of storage modulus G′. Moreover, the nonlinear effect at small strains, generally referred to as the Payne effect, was investigated in the NBR/CuSO4 compounds based on different heat press times from 0 to 40 min. The increasing of G′ suggested that the NBR/CuSO4 compound became highly cross‐linked, producing a strong filler‐polymer interaction, with prolonged heat press time.