Research On Reinforcement Of High Temperature Vulcanized Silicone Rubber By Graphene And Multi-Walled Carbon Nano-Tubes

In this thesis we have studied HTV silicone rubber composites.Silicone rubber is reinforced by graphene and multi-walled carbon nanotubes.Although graphene and carbon nanotubes have exceptional mechanical,thermal and electrical properties but these fillers give only fraction of their original strength when mixed in polymer matrix due to poor dispersion and weak inter-facial forces between filler and polymer matrix.Numbers of different new strategies are adopted to attain better dispersion of these nano fillers within polymer matrix.Graphene oxide was prepared from graphite by using modified Hummers9 method and reduced to obtain reduced graphene oxide.Addition of reduced graphene oxide in to silicone rubber by two-roll mixing technique gave poor dispersion state.New techniques,based on sol-gel,were developed to improve the degree of dispersion of reduced graphene oxide in silicone rubber.Reduced graphene oxide was dispersed in sol gel and later this semi-solid sol-gel was:mixed in to silicone rubber.Reduced graphene oxide showed improved dispersion properties in silicone rubber.In another work this technique was extended to disperse multi—walled carbon nanotubes in silicone rubber.Prepared materials and composites were analyzed by SEM,TGA,XRD,FTIR and TEM.All samples were tested for mechanical and thermal properties to measure and compare the reinforcement effect with the increase and decrease of filler loading.