Properties of Natural Rubber Filled with Silica from Rice Husk Coated with Polyethylene

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Kanjarat Sukrat
Adisak Jaturapiree
Ekrachan Chaichana
Thanunya Saowapark

Abstract

          This study aimed to investigate cure characteristics and tensile properties of natural rubber filled with
silica from rice husk coated with polyethylene. The rice husk silica (SC/RH) was obtained after calcination rice husk at 700˚C. The results show that SC/RH containing 99% of silica with amorphous structure. The SC/RH was improved with polyethylene (PE) through in situ polymerization comparing with the commercial silica (SC/com). It was found that the silica surface was coated with PE. For further study, untreated silica (SC/RH and SC/com) and PE treated silica (SC/RH-PE and SC/com-PE) were introduced as filler into natural rubber (NR). The experimental results obviously show that the decrease in cure time and the increase in torque difference and tensile strength of NR composites with incorporation of PE treated silica. This is due to the reduction of the adsorption of curing accelerator and filler-filler interaction on the silica surface via PE leading to the improvement in rubber - filler interaction which corresponded well with bound rubber result.

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Research Articles

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