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Critical Evaluation of the Microwave Effect on Radical (Co)Polymerizations

✍ Scribed by Yungwan Kwak; Robert T. Mathers; Krzysztof Matyjaszewski


Publisher
John Wiley and Sons
Year
2011
Tongue
English
Weight
613 KB
Volume
33
Category
Article
ISSN
1022-1336

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✦ Synopsis


Abstract

Critical evaluations of the microwave effect on initiation, propagation, and termination during conventional radical polymerizations (RPs) of methyl methacrylate (MMA) and random copolymerization of styrene (St) with (meth)acrylates are examined by comparing microwave heating (MWH) and conventional heating (CH). Poly(methyl methacrylate) with similar $ \overline M_{\rm n} $, $ \overline M_{\rm w} $/$ \overline M_{\rm n} $, and conversion are obtained under precisely controlled temperature, indicating very small changes of propagation rate constant. Rate enhancement in the absence of precise temperature control is mostly due to the higher reaction temperature of the reaction mixture than the apparent value indicated on display. Rates of initiator decomposition under well‐controlled temperature are essentially the same for MWH and CH.


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