Multi-scale modification of aerospace silicone rubber damping material with wide temperature range

Abstract

Silicone rubber has stable performance in a wide temperature range. However, as its damping factor in the effective damping temperature range is small and the damping performance is limited, multi-scale modification is required. Firstly, the molecular scale modification was carried out, and the molecular structure was adjusted by changing the vinyl content and the addition amount of alkylhydrosilane. The results show that the growth of the vinyl side chain and the successful grafting of the alkyl hydrogen silane on the vinyl side chain increase the barrier of motion of the molecular chain and enhance the damping performance of the silicone rubber. When the vinyl content is 15%(mass fraction, the same as below) and the molar ratio of hydrosilane to vinyl is 3:1, silicone rubber exhibits the best damping performance. On this basis, the micro-scale modification was continued. The results showed that adding phenyl hydrogen-containing silicone oil improved energy absorption efficiency because of the synergistic effect of forming π-π strong interaction bonds and increasing relaxation time. When the damping agent is added at 2%, silicone rubber exhibits the best damping performance. The effective synergy of molecular scale and micro scale significantly enhances the damping performance of silicone rubber, and the multi-scale modification strategy is suitable for preparing damping silicone materials with wide temperature range.

Keywords

• silicone rubber
• damping performance
• dynamic mechanical analysis
• multi-scale modifi-cation