Novel phenomenon of autoacceleration in the free radical oxidative polymerization of vinyl monomers: a thermochemical approach

The development of anilinium 2-acrylamide-2-methyl-1-propanesulfonate (Ani-AMPS) monomer, confirmed by 1H NMR, 13C NMR, and FTIR, is systematically studied. Ani-AMPS contains two polymerizable functional groups, so it was submitted to selective polymerization either by free-radical or oxidative polymerization. Therefore, poly(anilinium 2-acrylamide-2-methyl-1-propanesulfonic) [Poly(Ani-AMPS)] and polyaniline doped with 2-acrylamide-2-methyl-1-propanesulfonic acid [PAni-AMPS] can be obtained. First, the acrylamide polymer, poly(Ani-AMPS), favored the π-stacking of the anilinium group produced by the inter- and intra-molecular interactions and was studied utilizing 1H NMR, 13C NMR, FTIR, and UV-Vis-NIR. Furthermore, poly(Ani-AMPS) fluorescence shows quenching in the presence of Fe2+ and Fe3+ in the emission spectrum at 347 nm. In contrast, the typical behavior of polyaniline is observed in the cyclic voltammetry analysis for PAni-AMPS. The optical properties also show a significant change at pH 4.4. The PAni-AMPS structure was corroborated through FTIR, while the thermal properties and morphology were analyzed utilizing TGA, DSC (except PAni-AMPS), and FESEM.

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Evaluation of addition rates of thiyl radicals to vinyl monomers by flash photolysis. 4. Solvent effects on rates of free-radical reactions. Addition of the p-aminobenzenethiyl radical to styrene

Journal of the American Chemical Society ◽

10.1021/ja00366a033 ◽

1982 ◽

Vol 104 (2) ◽

pp. 568-572 ◽

Cited By ~ 37

Author(s):

Osamu Ito ◽

Minoru Matsuda

Keyword(s):

Free Radical ◽

Solvent Effects ◽

Flash Photolysis ◽

Radical Reactions ◽

Vinyl Monomers ◽

Free Radical Reactions ◽

Thiyl Radicals

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Mechanochemical Reactions Leading to Reinforcement in Rubbers

Rubber Chemistry and Technology ◽

10.5254/1.3542230 ◽

1960 ◽

Vol 33 (4) ◽

pp. 929-939

Author(s):

R. J. Ceresa

Keyword(s):

Free Radicals ◽

Free Radical ◽

Covalent Bond ◽

Vinyl Monomers ◽

Research Association ◽

Block Copolymerization ◽

Wide Range ◽

Carbon Gel ◽

Internal Mixer ◽

Mechanochemical Reactions

Abstract The development of the single rotor internal mixer (at the British Rubber Producers' Research Association) has facilitated the research into mechanochemical reactions of a wide range of high polymers. The term “mechanochemical” has been applied to reactions such as mastication, the mechanism of which involves the primary step of mechanical scission of a polymer chain into polymeric free radicals at a carbon to carbon or other covalent bond. The processes which have been studied previously include the cold mastication of rubberlike polymers, the formation of carbon gel, the interpolymerization of two elastomers during blending, and block copolymerization by the cold mastication of polymers plasticized by vinyl monomers. The evidence for the polymeric free radical nature of these reactions has recently been reviewed.

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Universal xanthate-mediated controlled free radical polymerizations of the “less activated” vinyl monomers

Journal of Polymer Science Part A Polymer Chemistry ◽

10.1002/pola.24320 ◽

2010 ◽

Vol 48 (22) ◽

pp. 5206-5214 ◽

Cited By ~ 23

Author(s):

Yuefang Yan ◽

Wei Zhang ◽

Yansheng Qiu ◽

Zhengbiao Zhang ◽

Jian Zhu ◽

...

Keyword(s):

Free Radical ◽

Vinyl Monomers ◽

Radical Polymerizations

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Evaluating the Effect of Termination by Chain - Chain Coupling in Living Free-Radical Polymerizations

Australian Journal of Chemistry ◽

10.1071/ch03041 ◽

2003 ◽

Vol 56 (8) ◽

pp. 775 ◽

Cited By ~ 15

Author(s):

Jeffrey Pyun ◽

Ian Rees ◽

Jean M. J. Fréchet ◽

Craig J. Hawker

Keyword(s):

Free Radical ◽

Star Polymers ◽

Star Polymer ◽

Direct Result ◽

Vinyl Monomers ◽

Linear Polymers ◽

Radical Coupling ◽

Novel Approach ◽

Vis Spectroscopy ◽

Radical Polymerizations

A novel approach based on the reaction of multifunctional star polymers with chromophore-labelled linear polymers is presented for evaluating the extent of termination by chain–chain coupling during living free-radical polymerizations. A mixed initiating system consisting of an unlabelled, multifunctional initiator and an excess of a monofunctional alkoxyamine initiator containing a chromophore, such as pyrene, is used to initiate the living polymerization of vinyl monomers leading to a mixture of star and linear polymers. The occurrence of chain–chain coupling is readily identified and quantified by isolating the star polymer that is obtained and elucidating the level of incorporation of pyrene units by UV/vis spectroscopy. This allows the level of chain–chain coupling to be determined since the inclusion of pyrene into the star structure is a direct result of termination by radical coupling.

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