Polystyrene (PS) was obtained from Total Petrochemical. Natural rubber latex (NRL, 61.61% dry rubber content) was supplied by ZARM Scientific & Supplies (Malaysia) Sdn. Bhd. Natural rubber latex waste (WL) was collected from the latex laboratory of the School of Materials and Mineral Resource Engineering at Universiti Sains Malaysia. Styrene graft natural rubber (SNR) was prepared referring to work by Tho (Tho, 2000 ). Deproteinized natural rubber (DPNR) was obtained from Sumirubber Industries (M) Sdn. Bhd. (Sungai Petani, Malaysia). Styrene monomer was purchased from Fluka Chemical Company (M) Sdn. Bhd. (Kuala Lumpur, Malaysia). Ammonium persulfate (NH4)2S2O8 was supplied by Fluka Chemical Company (M) Sdn. Bhd. (Kuala Lumpur, Malaysia). Styrene butadiene rubber (SBR) was obtained from Bayer (M) Co., Ltd and chloroform was supplied by Merck Sdn. Bhd.