Abstract: In this paper we wish to report our results on investigation of the kind and the concentration of the hydroperoxides initiators on the polymerization rate. Four kinds of peroxides with different concentration have been examined such as), tert-butyl hydroperoxide (TBHP), cumene hydroperoxide (CHP), methyl ethyl ketone hydroperoxide (MEKP) and benzoyl peroxide (BP). Results show that the rate of the reaction depends on the type and percentage of initiators.