Effect of Natural Antioxidants on Curing Characteristics and Crosslink Density of Natural Rubber Vulcanisate

摘要

Oil palm leaves is a waste material. Phenolic compound was extracted from oil palm leaves and know as natural antioxidant that could possibly used in natural rubber compound. The present study involves the effect of natural antioxidants that obtained from oil palm leaves on cure characteristics and crosslink density of natural rubber vulcanisate. The natural rubber had been cured at 160°C in three different vulcanization systems which were conventional (CV), efficient (EV) and semi-efficient (SEV). The cure characteristic was been conducted by using Mosanto Rheometer at 160°C for 30 minutes. For swelling test, the specimens were immersed in toluene solvent for 22 hours. The specimens were weighed before and after immersed. CV system showed better result in M90 and curing rate due to higher degree of crosslinking as compared to SEV and EV system. Meanwhile, EV and SEV system showed comparable result in crosslink density with CV system. This is due stronger bonding between monosulphide crosslink. Finally, the results indicated that natural antioxidant has a tendency to substitute commercial antioxidant (TMQ) in the rubber field.