Green and Simple Method for Catalytic Hydrogenation of Diene-Based Polymers

Catalytic hydrogenation of diene-based polymers is investigated in bulk form with different types of homogeneous and heterogeneous catalysts. Among these catalysts, we found that RhCl(PPh₃)₃, which could be promoted by its co-catalyst ligand (PPh₃), was able to diffuse into the bulk polymer. It was shown that a required high conversion (95?mol?%) was achieved within a few hours for the hydrogenation of acrylonitrile-butadiene rubber, styrene-butadiene rubber, and polybutadiene rubber using this catalyst. As an example, the hydrogenation of NBR in bulk form was investigated with respect to the effects of reaction temperature, pressure, and catalyst loading in an attempt to understand the hydrogenation of the bulk polymer.