Phosphorylated Cashew Nut Shell Liquid Prepolymer Modified Kaolin as a Reinforcing Filler for Rubber Vulcanizates—Comparison with SRSO Modified Kaolin and Cloisite

Abstract

NR (natural rubber) based and its blend with BR (polybutadiene rubber) and NBR (nitrile rubber) composites were synthesized using reinforcing filler and other relevant additives. PCNSL (phosphorylated cashew nut shell liquid) modified kaolin, SRSO (sodium salt of rubber seed oil) modified kaolin and commercially available cloisite 30b were used as filler for reinforcement to achieve improved mechanical properties. Kaolin was modified with PCNSL either in two methods, by solvent treated method or sodium salt method and varying concentrations were prepared for comparison. No rate of intercalation was found with solvent treated PCNSL, but achieved with sodium salt of PCNSL. While comparing SRSO and SPCNSL, it is found that better intercalation and property improvement were achieved with only SRSO, since it possesses up to 18 carbon atoms in the side chain than the PCNSL with 15 carbon atoms side chain.