Room temperature‐vulcanized silicone elastomer: Effect of curing conditions and the nature of filler on mechanical and thermal properties

Abstract

Abstract Linear poly(dimethylsiloxane diol) of about 650 D.P. was synthesized by hydrolytic condensation of dimethyldichlorosilane in a saturated solution of sodium chloride. The polymer was then compounded with various fillers, Cab‐O‐Sil, Dicalite, and titanium dioxide, and cured at room temperature in the presence of tin salt and tri‐ or tetrafunctional silane. The tensile strength and elongation of the unfilled rubber were found to be 0.8 kg/cm 2 and 320%, respectively. However, Dicalite White (100 phr)‐reinforced elastomer showed a tensile strength of 40 kg/cm 2 . Crosslink density was determined from the swelling studies. Thermal aging at 150, 200, and 250°C was also studied.