title: Critical evaluation of the microwave effect on radical (co)polymerizations.
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.
authors.affiliation: Center for Macromolecular Engineering, Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
authors.forename: Yungwan
authors.initials: Y
authors.lastname: Kwak
authors.forename: Robert T
authors.initials: RT
authors.lastname: Mathers
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Matyjaszewski
mesh_terms: D060326:Chemistry Techniques, Synthetic / Q000295:instrumentation / Q000379:methods*; D007700:Kinetics; D020366:Methylmethacrylate / Q000737:chemistry; D008872:Microwaves; D058105:Polymerization; D011108:Polymers / Q000138:chemical synthesis* / Q000737:chemistry; D020058:Styrene / Q000737:chemistry; D013696:Temperature
chemical_list: D011108:Polymers; D020366:Methylmethacrylate; D020058:Styrene