CONTROLLED THERMAL POLYMERIZATION OF STYRENE IN PRESENCE OF MOLECULAR BROMINE AND ELEMENTAL FE(0)

In this work, molecular Bromine (Br2) and zero-valent iron (Fe(0)) were used as the catalyst in the thermal polymerization of styrene (St) without any additional initiator at 110 °C. The polymerizations indicated controlled characteristics at appropriate molar ratio of Fe(0) to Br2, i.e., a remarkable increase of molecular weights with St conversion and the narrow molecular weight distributions. Gel permeation chromatography (GPC) results of the polymer are presented here and PDI values and molecular weight of thermal polymerization of St in the presence or absence of Br2 and Fe(0) were investigated and it can be seen that the number average molecular weight (Mn,GPC) increases almost linearly and remarkably with conversion. Effect of Br2 and Fe(0) on the kinetics were also studied and good results were obtained. The polymerization is regulated by in situ generated FeIIIBr3 by reaction of Br2 and Fe(0). The results suggested that the Fe(0)/Br2 catalyzing polymerization is a classical atom transfer radical polymerization (ATRP) process with easier operation and more economical components. This method is widely used in the synthesis of polymers with specific application, and almost every industry such as petroleum industry is dependent on it in some or the other way.

کلیدواژه ها:

Controlled Radical Polymerization ، Molecular Bromine (Br2) ، Elemental Fe(0) ، Atom Transfer Radical Polymerization (ATRP)