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

Autor: M. Najafi, H. Roughani Mamaghani, M. Salami-Kalajahi, V. Haddadi-Asl
Jazyk: perština
Rok vydání: 2009
Předmět:
Zdroj: علوم و تکنولوژی پلیمر, Vol 22, Iss 1, Pp 11-19 (2009)
Druh dokumentu: article
ISSN: 1016-3255
2008-0883
DOI: 10.22063/jipst.2009.688
Popis: 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).
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