The influence of both electron beam irradiation and step-crosslinking
process on the high abrasion furnace (HAF) carbon black loaded natural rubber
(NR) vulcanizates are reported. With irradiation, a higher crosslinking density,
ν, thermal conductivity, λ, glass transition temperature, Tg, and decreased
specific heat capacity, Cp, have been observed for the irradiated materials as
compared with the unirradiated ones. Meanwhile, the step-crosslinking process
has a slight effect on the crosslinking density, glass transition temperature and
thermal properties of these composites. The results of such changes in thermal
conductivity are explained with the help of a simple modified model.