Hydrogenated Natural Rubber from Different Types of Preserved Latex

摘要

One of the major disadvantages of natural rubber (NR) is poor ozone and ageing resistance besides poor oil and chemical resistance. These weaknesses are partly caused by the double bonds present in the rubber molecules. However the number of double bonds can be reduced by hydrogenation. This paper discusses the effect of preservation systems of NR latex used as the starting materials and also the effect of hydrogen peroxide on the efficiency of the hydrogenation reaction. The hydrogenated NR was prepared by reacting NR latex with hydrazine hydrate and hydrogen peroxide. The rubber was characterised by using proton Nuclear Magnetic Resonance (NMR). The results showed that the hydrogenation level is significantly affected by the different preservation systems and the concentration of hydrogen peroxide. The optimum level of hydrogen peroxide concentration was found to be in the range of 20-30% for all types of preservation systems. The use of field latex as a starting material achieved a much higher hydrogenation level (67%) compared to other types of preserved latex examined.