Coordination Crosslinking of Acrylonitrile-Butadiene Rubber and its Properties

A novel vulcanization method, vulcanization through metal coordination crosslinking, is developed. In this method copper sulfate (CuSO4) particles are simply incorporated into acrylonitrile-butadiene rubber (NBR), and no other vulcanizing agent nor additional additives are involved. It is totally different from traditional covalent or non-covalent vulcanization approaches of rubber. The crosslinking of CuSO4 particles filled NBR was induced by in situ coordination between nitrogen atoms of nitrile groups (-CN) and copper ions (Cu2+) from CuSO4. Several factors including heating temperature and time, the contents of CuSO4 and nitrile groups were investigated in this paper. The generation of a core (CuSO4 solid particle) -shell (adherent NBR) structure leads to the excellent mechanical properties of the coordination vulcanizates.