'Preparation and properties of silicone rubber thermal insulation composites'

Hollow glass bead(HGB)/ high tempe-rature vulcanized silicone rubber(HTV) and expan-ded vermiculite(EVMT)/HTV thermal insulation composites were prepared using HGB and EVMT as thermal insulation fillers blended with HTV, respectively. The effects of type and amount of thermal insulation fillers on the thermal insulation and mechanical properties of thermal insulation composites were investigated. The results showed that with the increasing amount of HGB and EVMT, the thermal conductivity of the thermal insulation composite decreased obviously. Compared with HTV, when the mass ratio of HGB to HTV was 20/100 and the mass ratio of EVMT to HTV was 10/100, the thermal conductivity of the thermal insulation composites decreased by 20.44% and 12.34%, respectively. Both HGB and EVMT could improve the modulus at 100% and Shore A hardness of HTV thermal insulation composites, and reduce its tensile strength and elongation at break. When the mass ratio of HGB to HTV was 20/100, and the mass ratio of EVMT to HTV was 10/100, the tensile strength of the thermal insulation composite were 10.51 MPa and 11.59 MPa, and Shore A hardness were 71.6 and 59.1, respectively.