End-Use Properties of Pineapple Leaf Fibre Filled Natural Rubber

The effects of incorporating pineapple leaf fibre (PLF) as a filler on the end-end properties of natural rubber vulcanizates were studied at different filler contents and particle sizes. The pineapple leaf fibre was used within filler contents, 0 to 40 phr at the following filler particle sizes, 75, 150 and 300 μm. The PLF was characterized for filler properties while carbon black (N330) served as the reference filler. The natural rubber vulcanizates were compounded on a two-roll mill. Results showed that the abrasion resistance of filled natural rubber vulcanizates was generally higher than that of the unfilled natural rubber vulcanizate at filler content, 5 phr, and for PLF (150 and 300 μm) and carbon black filled natural rubber vulcanizates, the abrasion resistance decreased within filler content, 5 to 20 phr after which it increased with filler content. CB exhibited better abrasion resistance in the vulcanizates than PLF at filler contents greater than 20 phr. The hardness of filled natural rubber vulccanizates was generally greater than that of unfilled vulcanizate and increased with increases in filler particle size at filler contents, 10 and 20 phr. The specific gravity of the rubber vulcanizates increased gradually with the increase in filler content at filler content greater than 5 phr, and increased with increases in filler particle size at any filler content considered. The swelling index of filled natural rubber vulcanizates in toluene generally decreased with increasing filler particle size at filler contents, 5, 10 and 40 phr whereas the swelling index for PLF (150 μm) filled natural rubber decreased with increases in filler content. CB filled vulcanizates absorbed the highest amount of toluene (2.5%) in the vulcanizates at filler content, 40 phr. PLF (150 and 300 μm) generally gave optimum performances in the end-use properties of the rubber vulcanizates determined within filler contents, 30 and 40 phr. The incorporation of pineapple leaf fibre into natural rubber was found to improve the end-use properties of natural rubber vulcanizates and therefore, has potential in the formulation of natural rubber products.