Isolobal Zwitterionic Niobium and Tantalum Imido and Zirconium Monocyclopentadienyl Complexes: Theoretical and Methyl Methacrylate Polymerization Studies

2008 ◽  
Vol 27 (7) ◽  
pp. 1417-1426 ◽  
Author(s):  
Rocío Arteaga-Müller ◽  
Javier Sánchez-Nieves ◽  
Javier Ramos ◽  
Pascual Royo ◽  
Marta E. G. Mosquera
Keyword(s):  
Methyl Methacrylate ◽  
Methyl Methacrylate Polymerization

Methyl methacrylate polymerization involving a cobalt ortho-iminobenzosemiquinone complex: Determination of the chain transfer constant

2015 ◽  
Vol 56 (3) ◽  
pp. 267-275 ◽  
Author(s):  
E. V. Kolyakina ◽  
Yu. E. Ovchinnikova ◽  
I. D. Grishin ◽  
A. I. Poddel’skii ◽  
D. F. Grishin
Keyword(s):  
Methyl Methacrylate ◽  
Chain Transfer ◽  
Transfer Constant ◽  
Methyl Methacrylate Polymerization ◽  
Chain Transfer Constant

On the Mechanism of Radical Polymerization of Methyl Methacrylate with Dithiobenzoic Acid as Mediator

2006 ◽  
Vol 59 (8) ◽  
pp. 549 ◽  
Author(s):  
Duc Hung Nguyen ◽  
Philipp Vana
Keyword(s):  
Methyl Methacrylate ◽  
Induction Period ◽  
Hydrogen Abstraction ◽  
Ester Group ◽  
Reaction Scheme ◽  
Ionization Mass ◽  
Controlled Polymerization ◽  
Induction Periods ◽  
Methyl Methacrylate Polymerization ◽  
Raft Agent

Dithiobenzoic acid (DTBA) induces controlled polymerization behaviour in methyl methacrylate polymerization at 60°C, accompanied by a pronounced induction period of several hours. DTBA is partially transformed during this induction period into a dithioester with a tertiary ester group moiety, which constitutes an efficient reversible addition–fragmentation chain transfer (RAFT) agent. The transformation reaction is proposed to proceed via a hydrogen abstraction from DTBA by radicals and subsequent termination of the formed phenylcarbonothioylsulfanyl radical with propagating radicals. The proposed reaction scheme was implemented into a computer model, by which the rate coefficient of the hydrogen abstraction from DTBA and of the reinitiation of the intermediate phenylcarbonothioylsulfanyl radical was estimated. The model is in agreement with all of the species observable by electrospray ionization mass spectrometry, with the extent of the experimental induction periods, and with the absolute concentrations of dithioesters that act as efficient RAFT agents during the polymerization. A protocol that uses a cocktail of initiators is introduced, by which the induction period in DTBA-mediated polymerization is effectively eliminated.

Synthesis, Structure, and Methyl Methacrylate Polymerization Activity of a Mixed π-Ferrocene π-Toluene Complex of Potassium Tris(hexamethyldisilazide)magnesiate

2004 ◽  
Vol 23 (6) ◽  
pp. 1197-1199 ◽  
Author(s):  
Gordon W. Honeyman ◽  
Alan R. Kennedy ◽  
Robert E. Mulvey ◽  
David C. Sherrington
Keyword(s):  
Methyl Methacrylate ◽  
Methyl Methacrylate Polymerization
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