Effect of split addition of initiator and antioxidant in radiation vulcanised natural rubber latex

In radiation vulcanisation of natural rubber latex (RVNRL), the crosslinking of rubber particles is brought about by γ-radiation from a 60Co source. The optimum radiation dose for obtaining maximum properties for RVNRL film is 15 k.Gy. The residual n-BA in the latex causes several problems in the products derived from the latex. The split dose addition of n-BA was proposed to overcome this difficulty. The order of addition of antioxidants also has some effect on radiation crosslinking reaction as antioxidants are the free radical scavengers. Accordingly, the effect of different modes of addition of antioxidant, on mechanical properties of the vulcanisates, was studied. Among the different methods attempted the addition of antioxidant at mid time (M.I) and after irradiation (A.I) registered better mechanical properties and better thermal stability.