Journal ArticleDOI
Chain Transfer Activity of ω-Unsaturated Methyl Methacrylate Oligomers
TLDR
In this article, the chain transfer activities of a series of ω-unsaturated methyl methacrylate oligomers (dimer, trimer, tetramer, and a higher macromonomer with average chain length of 24 units) were evaluated over the temperature range 45−100 °C.Abstract:
The chain transfer activities of a series of ω-unsaturated methyl methacrylate oligomers [(dimer (1), trimer (2), tetramer (3), and a methyl methacrylate macromonomer with average chain length of 24 units (4)] have been evaluated in methyl methacrylate polymerizations over the temperature range 45−100 °C. Transfer constants were determined by analysis of the ln chain length distributions. The dimer (1) was found to be substantially less effective as a chain transfer agent than the trimer (2) or the higher macromonomers (3, 4) [CT(60 °C) 1, 0.013; 2, 0.19; 3, 0.31; 4, 0.21]. The transfer constants show only a small temperature dependence and no variation with conversion. No discernible retardation was observed in these polymerizations. A reduced yield of polymer observed at conversions >10% in bulk polymerizations of MMA carried out in the presence of 1−4 can be attributed to the absence of the gel (Trommsdorff) effect. The results are interpreted in terms of the addition−fragmentation mechanism for chain ...read more
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Journal ArticleDOI
Living free-radical polymerization by reversible addition - Fragmentation chain transfer: The RAFT process
John Chiefari,Y. K. Chong,Frances Ercole,Julia Krstina,Justine Leigh Jeffery,Tam P. T. Le,Roshan T. A. Mayadunne,Gordon Francis Meijs,Catherine Louise Moad,Graeme Moad,Ezio Rizzardo,San H. Thang +11 more
TL;DR: The authors proposed a reversible additive-fragmentation chain transfer (RAFT) method for living free-radical polymerization, which can be used with a wide range of monomers and reaction conditions and in each case it provides controlled molecular weight polymers with very narrow polydispersities.
Journal ArticleDOI
Controlled/living radical polymerization: Features, developments, and perspectives
TL;DR: In this article, a review of recent mechanistic developments in the field of controlled/living radical polymerization (CRP) is presented, with particular emphasis on structure-reactivity correlations and "rules" for catalyst selection in ATRP, for chain transfer agent selection in reversible addition-fragmentation chain transfer (RAFT) polymerization, and for the selection of an appropriate mediating agent in stable free radical polymerisation (SFRP), including organic and transition metal persistent radicals.
Journal ArticleDOI
Living radical polymerization by the RAFT process
TL;DR: A review of living radical polymerization achieved with thiocarbonylthio compounds by a mechanism of reversible addition-fragmentation chain transfer (RAFT) is presented in this article.
Journal ArticleDOI
Radical addition-fragmentation chemistry in polymer synthesis
TL;DR: In this paper, a review of the development of addition-fragmentation chain transfer agents and related ring-opening monomers highlighting recent innovation in these areas is presented, including dithioesters, trithiocarbonates, dithioco-baramates and xanthates.
Journal ArticleDOI
Kinetics of Living Radical Polymerization
Atsushi Goto,Takeshi Fukuda +1 more
TL;DR: In this article, a review of fundamental kinetic features of living radical polymerization (LRP) is presented, where the authors show that the product from LRP can have a low polydispersity, provided that the number of terminated chains is small compared to the number potentially active.
References
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TL;DR: In this article, the Smith-Ewart equation chain-length-dependent kinetics of particle growth is described and a roadmap for modelling particle growth conclusions is provided. And the particle size distributions are discussed.
Journal ArticleDOI
Formation of CC Bonds by Addition of Free Radicals to Alkenes
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Journal ArticleDOI
Zur polymerisation des methacrylsäuremethylesters1
TL;DR: In this paper, the authors describe the Polymerisation des Methacrylsauremethylesters with Benzoylperoxyd (BPE) with a periode stationarer Geschwindigkeit, beginnend bei etwa 20 bis 25% Umsatz with starker Beschleunigung (explosionsartiger Polymerisationsverlauf nach G. V. Schulz and Blaschke).