Preparation and Characterization of Exfoliated Layered Double Hydroxide/Silicone Rubber Nanocomposites

Silicone rubber (SR)/Mg-Al layered double hydroxide (LDH) nanocomposites were prepared by the solution intercalation of SR crosslinked by a platinum-catalyzed hydrosilylation reaction into the galleries of dodecyl sulfate intercalated layered double hydroxide (DS-LDH). X-ray diffraction and transmission electron microscopy analysis showed the formation of exfoliated structures of organomodified LDH layers in the SR matrix. The tensile strength and elongation at break of SR/DS-LDH (5 wt %) were maximally improved by 53 and 38%, respectively, in comparison with those of the neat polymer. Thermogravimetric analysis indicated that the thermal degradation temperature of the exfoliated SR/DS-LDH (1 wt %) nanocomposites at 50% weight loss was 20 degrees C higher than that of pure SR. Differential scanning calorimetry analysis data confirmed that the melting temperature of the nanocomposites increased at lower filler loadings (1, 3, and 5 wt %), whereas it decreased at a higher filler loading (8 wt %). The relative improvements in the solvent-uptake resistance behavior of the SR/DS-LDH nanocomposites were also observed. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 119: 343-351, 2011