Investigation of crosslinking kinetics of silicone rubber/POSS nanocomposites

This study focus on investigation peroxide crosslinking kinetics of silicone rubber/Poly Oligomeric Silsesquioxane (POSS) nanocomposites by using a nonlinear phenomenological model and also evaluating performance of the model on peroxide vulcanization of silicone. In composite materials, silicone is needed to adhere reinforcing fibers in order to maintain internal pressures. POSSs can be used to improve the adhesion between silicone and common reinforcing fibers such as Kevlar and Rayon through the polar and/or reactive groups which are able to join the chemical structure during crosslinking process. In this study, Octavinyl-POSS (O-POSS), Methacryl-POSS (M-POSS), and octamaleamic acid-POSS (OM-POSS) are incorporated to a reference silicone compound. Effects of POSS type and ratio on the vulcanization kinetics are studied. It is revealed that this model can be successfully used for the nanocomposites. The kinetic parameters are found to be consistent with proposed reaction mechanisms and with rheological variations due to POSS incorporation.