Synthesis of Poly Dimethyl Siloxane with Terminal Hydroxyl Groups

A variety of polymer such as: ethyl cellulose, Cellulose acetate, polyester and etc have been served widely in insulation of double-base solid propellant. Proper insulation of double base propellants should have features such as: 1- low absorption NG; 2- Without or low producion of smoke; 3- good adhesion of insulator to propellants surface; 4- with suitable vanished and thermal parameters and etc. In this paper polymer used in insulation of double base propellant are reviewed and their physical and chemical characteristic are investigated and compared. Then hydroxyl terminated poly dimethylsiloxane was synthesized and the effect of temperature, reaction time, ratio of raw material, type and intensity of agitation, type of catalyst, solvent and quenching reagents on molecular weight of poly dimethysiloxane was studied. Also a new method for one step synthesis of a hydroxyl terminated polydimethylsiloxane is presented.