The polarity of epoxidised natural rubber (ENR) was improved by grafting it with cassava starch (CSt). A graft copolymer between ENR and CSt (ENR-g-CSt) was synthesised from CSt solution and ENR latex by using K2S2O8 as an initiator. The highest percentage efficiency of grafting was obtained with 10 parts per hundred (phr) CSt. The swelling ratio of the ENR-g-CSt particles also decreased as a function of the CSt in the sample due to the polarity of the incorporated CSt. After synthesis, it was used as an impact strengthening agent for a polymer blend. Chemically modified NR polymers can form the basis of many value-added NR products that are environmentally friendly and cost effective for use as biopolymers in the future.
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