Effect of silicone rubber based impact modifier on mechanical and flammability properties of plastics recovered from waste mobile phones

The plastics recovered from electronic waste have huge potential to be recycled into new products. However, several earlier works have indicated that the toughness properties of the recovered plastics are significantly low. An impact modifier for such plastics was developed in the current study using silicone rubber waste from mobile phone keypads. The silicone rubber keypads were partially de-vulcanized by a thermo-mechanical process and were further grafted with methyl methacrylate to improve its compatibility with the recovered plastics, also from mobile phone waste. The effect of the silicone rubber based impact modifier on mechanical properties, particularly toughness under room temperature and cryogenic temperatures were analyzed. The effect of silicone impact modifier on visco-elastic properties and flammability of the plastics recovered from mobile phone waste was studied. The results revealed that the addition of silicone rubber based impact modifiers improves the toughness of the recovered plastics to a great extent and also that the improvement in toughness is maintained at cryogenic temperatures. The flame retardancy of the recovered plastics improved tremendously on addition of silicone rubber-impact modifier.