Reinforcement of natural rubber vulcanisates by hydroxyl-terminated liquid natural rubber grafted carbon black

Abstract

This paper deals with the grafting of acyl chloride capped liquid natural rubber (LNR-COCI) onto carbon black by the reaction of the acyl chloride group with the phenolic hydroxyl group on the surface. LNR-COCI was prepared by the reaction of hydroxyl-terminated liquid natural rubber (HTNR) with adipoyl dichloride. The percentage of grafting was estimated to be 18-21% depending on the grafting temperature and the molecular weight of HTNR used. It increased with an increase in the molecular weight of LNR-COCI. The LNR grafted onto carbon black was investigated by IR spectroscopy and by hydrolysis with a dilute THF solution of KOH. It was shown that LNR grafted onto the carbon black surface with ester bonds. The liquid natural rubber-grafted carbon black (LNR-CB) thus obtained, was used to improve the morphological and mechanical properties of NR vulcanisates. Advances in Natural Sciences Vol.4, No.4 (2003) (303-311)