Study of Atom Transfer Radical Polymerization of Styrene and Its Gel Effect by Monte Carlo Simulation Method

Najafi, M.; Roughani Mamaghani, H.; Salami-Kalajahi, M.; Haddadi-Asl, V.

doi:10.22063/jipst.2009.688

Study of Atom Transfer Radical Polymerization of Styrene and Its Gel Effect by Monte Carlo Simulation Method

Document Type : Research Paper

Authors

M. Najafi

H. Roughani Mamaghani

M. Salami-Kalajahi

V. Haddadi-Asl

10.22063/jipst.2009.688

Abstract

Atom transfer radical polymerization (ATRP) of styrene was carried out at 105°C and a Monte Carlo simulation was employed to model the system. The variations of monomer conversion, the initiator concentration, average molecular weight, and molecular weight distribution were evaluated as the reaction proceeded. According to the results obtained, for similar reaction time, monomer conversion is higher when gel effect is taken into account. Also, the concentration of initiator suddenly drops at the initial stages of polymerization, and finally reaches zero. In addition, in the presence of gel effect, bimolecular termination rate constant decreases during the polymerization. Moreover, number- and weight-average molecular weights linearly rise as the polymerization progresses; this also is a confirmation to the living nature of the polymerization. Finally, the molecular weight distribution of polymers synthesized narrows at high monomer conversion. In effect, polydispersity index decreases from about 2 (at the onset of polymerization) to around 1.3 (towards the end of polymerization).

Keywords

Polystyrene

ATRP

Monte Carlo simulation

gel effect

polydispersity index