Copolymerization of Methyl Methacrylate and Dodecyl Methacrylate Initiated by Bifunctional Peroxide

Ljubica Tomašek, Ante Jukić, and Zvonimir Janović*
Faculty of Chemical Engineering and Technology, University of Zagreb, Marulićev trg 19, P.O. Box 177,
HR-10000 Zagreb, Croatia E-mail: zjanov@fkit.hr

Abstract
This paper deals with the kinetic study of methyl methacrylate (MMA) and dodecyl methacrylate (DDMA) free radical polymerization initiated with the bifunctional initiator 1,1-di(tertbutylperoxy)cyclohexane (BPCH). The reactions were carried out in xylene solution up to high conversions in an isothermal reaction calorimeter. The results were compared with values obtained by using dibenzoyl peroxide as a conventional monofunctional initiator. The influence of monomer mixture composition and initiator functionality on initial reaction rate, conversion and polymer molecular mass distribution was described and discussed. The polymerization rate was found to be in the order: DDMA > DDMA/MMA > MMA for both type of initiators, with significantly higher values obtained by using BPCH. It was established that in polymerizations initiated with BPCH high reaction rates and high polymer molecular masses were achieved simultaneously. As a result, the short-cycle reactions with reduction in polymerization time of up to 50% were accomplished with the bifunctional initiator at appropriate polymerization temperature.

Key words: methyl methacrylate, dodecyl methacrylate, bifunctional peroxide initiator, polymerization, kinetics