Preparation and Properties of Hollow Glass Microsphere/Silicone Rubber Composite Material with the Transition Layer of Silicone Resin

Hollow glass microsphere (HGM)/silicone rubber composite material was prepared by using silicone resin as the transition layer between silicone rubber and HGM. Silane coupling agent was hydrolyzed on the surface of HGM by in-situ polymerization to form the silicone resin layer. And then such modified HGM was added to the silicone rubber to prepare HGM/silicone rubber composite material. The curing process, mechanical property, morphology, thermal stability, and electrical property were studied. It is found that the transition layer of silicone resin can speed up the curing reaction. And the curing time becomes longer with the increase of HGM. The transition layer of silicone resin also improves the compatibility between HGM and silicone rubber. And the mechanical properties of the silicone rubber are reduced with the increase of HGM. The introduction of HGM can improve the thermostability of the silicone rubber. And HGM can obviously reduce the dielectric constant (from 3.4 to 2.6) and increase the dielectric breakdown strength (from 14.78 kV/mm to 16.71 kV/mm) of the samples.