PEEL STRENGTH AND MECHANICAL PROPERTIES OF THE SILICONE RUBBER/CLAY NANOCOMPOSITES

초록

Silicone rubber is suitable for the thermal insulator of the rocket motors owing to its heat resisting properties as well as its excellent elasticity and restoring force. However the adhesion properties of the silicone rubber should be improved greatly to be used as the thermal insulator because of its poor adhesiveness coming from the low surface tension. Functional groups were incorporated through copolymerization to the silicone rubber to induce chemical reaction with the functional groups in the propellant/liner components to enhance the adhesion properties. Room temperature valcanizing (RTV) silicone rubbers were compounded with silane coupling agent and carbon black. Natural sodium montmorilonite, MMT modified with γ-aminopropyltriethoxy silane and MMT modified with diamine compounds were also incorporated into the silicone rubber composites. The grafting of the silane compounds on the surface of the clay was verified with Fourier Transform Infrared Spectroscopy. Peel strength of the silicone rubber composites with the liner components was measured by using the T-peel test method. Addition of carbon black and APTES raised the peel strength of the silicone rubber composites. The peel strength increased further when the modified clays were incorporated into the silicone rubber. Mechanical properties and heat resistance of the silicone rubber composites measured by using UTM and TGA, respectively, were enhanced significantly as a result of the addition of the clays. Authors gratefully acknowledge the support by Defense Acquisition Program Administration and Agency for Defence Development