RADIATION GRAFT MODIFICATION OF ETHYLENE-PROPYLENE RUBBER .1. EFFECT OF MONOMER AND SUBSTRATE STRUCTURE

Radiation grafting of hydrophilic vinyl monomers onto ethylene propylene elastomers (EPM rubbers) by the simultaneous method was studied. The present work centres upon gamma radiation-induced grafting of acrylamide (AAm), N-vinyl-2-pyrrolidone (NVP), 2-hydroxyethyl methacrylate (HEMA) and acrylonitrile (AN) onto four different EPM rubbers. Metal-based homopolymerisation inhibitors including Mohr's salt, Cu(NO3)2 and FeSO4 were evaluated and found to prevent homopolymerisation and significantly increase graft yield. Lithium nitrate was evaluated as a graft promoter. The effect of oxygen upon grafting was also studied. The role of the type of EPM rubber on grafting efficiency for a variety of monomers was investigated, to optimise grafting conditions for each EPM rubber and monomer. The properties of the resulting copolymers have been studied by SEM techniques.