Study On The Properties Of Room Temperature Vulcanized Silicone Rubber Modified By Carbon Nano Materials

In the application of electrical industry,there is shortcomings of low conductivity,low thermal conductivity,and poor mechanical strength in the silicone rubber.Carbon materials with excellent performance was used to improve the properties of silicone rubber at low filler loading.This paper mainly studies the effect of trace(?0.2wt%)carbon nano fillers on properties of silicone rubber.First,graphene oxide(GO)and multi walled-carbon nanotubes(MWCNTs).were surface modified by ?-aminopropyl triethoxy silane(KH550)and 4,4'-diphenyl methane diisocyanate(MDI),respectively.Then carbon nano materials and ?,?-dihydroxy poly dimethyl diphenyl siloxane(phenyl silicone rubber),?,?-dihydroxy poly dimethyl siloxane(methyl silicone rubber)were blended by solution mixing method and cured at room temperature.The results showed that:(1)Two kinds of silicone rubber matrix composites are still insulated with trace amounts of fillers,the volume resistivity>1013??cm.(2)The light transmission of composites decreased with the increase of carbon nano fillers content.The transmittance of composites with modified carbon nano fillers was better in the ultraviolet region.(3)With the nano carbon materials,the thermal conductivity and tensile strength of methyl silicone rubber composites were higher than that of phenyl silicone rubber composites.At 0.2wt%of nano fillers,the thermal conductivity of phenyl silicone rubber composites with KH550 modified GO was increased by 56%,compared with that of pure silicone rubber(0.169W·mn-1·K-1).The tensile strength of methyl silicone rubber composites was increased by 67%,compared with that of pure methyl silicone rubber composites.(4)When the mass content of MDI modified GO was 0.2wt%,the Tg of the composite was-127.0?,which was 22.1? lower than that of the pure silicone rubber.