Solution homopolymerizations of n-butyl acrylate and styrene mediated using 2,2,5-trimethyl-4-tert-butyl-3-azahexane-3-oxyl (TITNO)

POLYMER

卷:55

Article

Cameron, Neil R.^1,2  Lagrille, Olivier^1,2  Lovell, Peter A.³  Thongnuanchan, Bencha³ 

[1] Univ Durham, Dept Chem, Durham DH1 3LE, England

[2] Univ Durham, Biophys Sci Inst, Durham DH1 3LE, England

[3] Univ Manchester, Ctr Mat Sci, Sch Mat, Manchester M13 9PL, Lancs, England

关键词: Nitroxide-mediated polymerization;    Alkoxyamine dissociation;    Kinetics;   

DOI  :  10.1016/j.polymer.2013.12.060

来源: Elsevier

【 摘 要 】

Use of Styryl-TITNO (the styrene alkoxyamine of 2,2,5-trimethyl-4-tert-butyl-3-azahexane-3-oxyl) as mediator for nitroxide-mediated polymerization (NMP) of n-butyl acrylate (BA) and styrene has been investigated at temperatures <= 110 degrees C. Very good control of molecular weight and molecular weight dispersity with no measurable loss of active chains, and no evidence of tails in the molecular weight distribution as conversion increases, was observed at 90 degrees C for BA and at 70 degrees C for styrene. The alkoxyamine dissociation equilibrium constant values determined for polyBA-TITNO (8.5 x 10(-11) mol L-1 at 90 C) and polystyrene-TITNO (3.1 x 10(-9) mol L-1 at 70 degrees C) are consistent with those required for control when using more established nitroxides that require higher temperatures to achieve these values. The lower optimum polymerization temperatures with Styryl-TITNO as mediator provide new opportunities for NMP and are especially significant for styrene since this appears to eliminate completely the complications from thermal initiation. (C) 2014 Elsevier Ltd. All rights reserved.

【 授权许可】

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