2. Materials
Deproteinized natural rubber latex (DPNR) having 22 % dry rubber content was supplied by
Rubber Research Institute Malaysia (RRIM). Formic acid 98 %, hydrogen peroxide 30 %, methanol was obtained from Fisher Scientific UK. Clear EP 331 with epoxide equivalent weight 182-192 was a liquid diglycidyl ether of bisphenol A, and curing agent was clear epoxy hardener 8161 (isophorone diamine) with amine value 260-284 (mg KOH/gm). Both EP and curing agent were obtained from Euro chemo- pharma, Sdn. Bhd.