EFFECT OF ANTIOXIDANTS ON MECHANICAL, PHYSICAL AND AGING PROPERTIES OF HYBRID RADIATION-PEROXIDE VULCANIZED LATEX

Oxidative aging of a rubber-based product occurs stepwise throughout its operating life; during the manufacturing processes and even during storage. Exposure to oxidation causes chemical, mechanical and physical changes resulting in declining functional performance. In order to inhibit the oxidation rate, this study is looking at the usage of antioxidant which was added into the radiation-peroxide vulcanized latex to trap or deactivate the free radicals. All the physical properties of the latex films were in compliance to the standard specifications. The addition indicated that 2.5 pphr of Aquanox Lp antioxidant offered superior effect compared to Irganox 1520 in slowing down the oxidative aging process of the hybrid RVNRL-peroxide latex films. The values of tensile stress, modulus at 500% and modulus at 700% were compared before and after accelerated aging test for 22 hours at 100oC and showed major drop of 1.3%, 42.2% and 46.3% respectively. Prolong aging via 7 days accelerated aging test at 70oC also showed that the values of the tensile stress, modulus at 500% and modulus at 700% dropped at 6.8%, 33.4% and 41.9%, respectively.