Organic Montmorillonite as a Substitute for Aerosilica in Addition‐Type Liquid Silicone Rubber Systems

Abstract

Abstract Summary: A novel addition‐type liquid silicone rubber (SR)/organic montmorillonite (OMMT) nanocomposite has been synthesized. N , N ‐Di(2‐hydroxyethyl)‐ N ‐dodecyl‐ N ‐methylammonium chloride was used as an intercalation agent to treat Na + ‐montmorillonite and form a novel kind of OMMT. Three types of SR/OMMT composites were synthesized with different amounts of OMMT, and were compared with an aerosilica‐modified SR system. Tensile strength, and other properties determined by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), were compared. A combination of Fourier‐transform infrared (FT‐IR) spectroscopy, wide‐angle X‐ray diffraction (WAXD), scanning electron microscopy (SEM), and transmission electronic microscopy (TEM) studies showed that SR/OMMT composites were on the nanometer scale, and the segmented structure of the SR was disrupted by the presence of OMMT, as a result of the reaction between the monomer and the intercalation agent. Results showed that the physical and mechanical properties of an SR system with 1 phr of OMMT were nearly equal to that of an SR system with 3 phr of aerosilica because of the exfoliation of the OMMT and the resultant nano‐effect in the system. WAXD spectra of the organic montmorillonite (OMMT)‐intercalated silicone rubber magnified image WAXD spectra of the organic montmorillonite (OMMT)‐intercalated silicone rubber