A new strategy for improving high‐temperature mechanical properties of HNBR/ZDMA composites through polymerization of ZDMA promoted by zinc methylmercaptobenzimidazole

Abstract

In this work, zinc methylmercaptobenzimidazole (MMBZ) was introduced into hydrogenated nitrile butadiene rubber (HNBR) matrix with zinc dimethacrylate (ZDMA) as a reinforcing filler to prepare HNBR/ZDMA composites. The effects of MMBZ on the crosslinking network, high‐temperature mechanical properties, and interfacial interaction between HNBR and poly(zinc dimethacrylate) (PZDMA) in the HNBR/ZDMA composites were systematically investigated using Fourier transform infrared spectroscopy (FTIR) and crosslinking density test. It was found that MMBZ accelerated the in situ polymerization of ZDMA to form PZDMA in the HNBR matrix. In addition, the results of FTIR, transmission electron microscopy, and stress–strain behavior at different temperatures also demonstrated that the MMBZ was able to facilitate the grafting of PZDMA onto the HNBR molecular chains, which obviously strengthened the interfacial interaction between HNBR and PZDMA. In comparison to the HNBR/ZDMA composite without MMBZ, the tensile strength and elongation at break of the HNBR/ZDMA‐MMBZ composite with 8 phr MMBZ at 130°C sharply increased from 9.8 MPa and 250% to 15.5 MPa and 305%, respectively. The strategy proposed in this work for the preparation of HNBR/ZDMA composites with high‐temperature mechanical properties is simple to produce on a large scale, which will further promote the development and application of HNBR.