Comparison Between Peroxide and Radiation Crosslinking of Nitrile Rubber

In the present study, two methods of nitrile rubber curing were compared: peroxide and radiation crosslinking. Both methods lead to formation of carbon–carbon crosslinks, directly between the polymer chains. The nitrile rubber samples were unfilled, and filled with silica, carbon black, organoclay and graphene nanoplatelets. The chain scission to crosslinking ratio was calculated on the basis of the Charlesby-Pinner equation. It was demonstrated that radiation curing results in lower number of chain scission events than peroxide thermal curing. Mechanical properties tests showed that the radiation-cured samples generally show better tensile strength and larger elongation at break than the peroxide-cured samples with the same values of crosslink density. It was proved that radiation curing can be successfully used to alter the properties of the composite materials based on nitrile rubber.