Talc modification with bis[3-(triethoxysilyl)propyl]tetrasulfide (TESPT)-based coating to improve the mechanical characteristics of silicone rubber

Abstract

Rubber is a main material of prosthetic foot products. A local product of Indonesian prosthetic foot is available in the market. However, the quality of the product need to be improved. Several material formulations have been made to make prosthetic foot more elastic, strong, and affordable. An optimization formula of talc powder reinforced silicone rubber has been carried out in the previous study. However, the bonding between talc powder and silicone rubber is weak. In the present study, the talc powder is coated with a bis[3-(triethoxysilyl)propyl]tetrasulfide (TESPT) in order to obtain strong bond between talc powder and silicone rubber. Mechanical characterizations were conducted to compare the composites with and without TESPT coating. The characterization include tensile and hardness tests. The tribometer tests are also conducted to compare both composites, it evaluates the value of friction and wear mass of the composites. The results show that the composites using coated talc powder can reduce wear and friction force. The friction and wear of composites containing coated talc powder is better than the local products. The hardness of the composites containing coated talc powder increases compared to those without coating. While the use of coated talc powder reduces the tensile strength and elongation at break.