Cationic ring opening polymerization of octamethylcyclotetrasiloxane initiated by solid superacid

Abstract

Kinetics of the cationic ring opening polymerization of octamethylcyclotetrasiloxane (D₄) in bulk initiated by solid superacid was studied. The optimalizing experimental conditions were based on preliminary experiments. Higher temperature was beneficial to equilibrium conversion while stirring intensity beyond a certain level displayed no obvious effect on the rate of the reaction. A kinetic model was elicited and kinetic parameters were obtained through optimization. The calculated activation energies were 32.6 and 34.1 kJ mol^–1 for D4 and all other annuluses (D_x), respectively.