Ionic Liquids ‐ New Solvents in the Free Radical Polymerization
Ionic Liquids ‐ New Solvents in the Free Radical Polymerization
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离子液体 - 自由基聚合中的新溶剂
DOI：
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发表时间：
2007
期刊：
影响因子：
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通讯作者：
A. Schmalfuss
中科院分区：
文献类型：
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作者：
G. Schmidt;I. Woecht;A. Schmalfuss
分析离子液体在聚合物合成中的作用是一个活跃的研究领域。[1]使用离子液体作为自由基聚合的溶剂意味着可以观察到聚合速率和分子量的显著增加。本文研究了苯乙烯（S）与甲基丙烯酸甲酯（MMA）、甲基丙烯酸缩水甘油酯（GMA）和甲基丙烯酸羟丙酯（HPMA）与丙烯腈（AN）在乙基3甲基咪唑乙基硫酸盐（[EMIM]EtSO 4）中的共聚行为。离子液体是具有相当高极性和粘度的液体。这两个特性与传播速率系数kp和终止速率系数kt密切相关。[2-4]终止的速率常数k t降低时，IL的浓度，因此反应混合物的粘度增加，而增长速率系数kp随着增加IL含量。IL的粘度可以通过使用IL与常规有机溶剂的混合物来改变-这里IL [EMIM]EtSO 4与DMF混合-或者通过改变温度来改变。研究了离子液体（[EMIM] EtS 04）的粘度对甲基丙烯酸甲酯（MMA）和苯乙烯/丙烯腈（S/AN）聚合动力学的影响。
The analysis of the influence of ionic liquids (ILs) in polymer synthesis as an alternative for common organic solvents is still an active field of research.[1] Using ILs as solvents for free radical polymerizations implies a significant increase in polymerization rates and molecular weights which can be observed. In this work we examined the copolymerization behaviour of styrene (S) and methyl methacrylate (MMA), glycidyl methacrylate (GMA) and 2-hydroxypropyl methacrylate (HPMA) with acrylonitrile (AN) in i-etyhl-3-methylimidazolium ethylsulfate ([EMIM]EtSO 4 ). ILs are liquids with comparable high polarities and viscosities. These two characteristic properties are strongly correlated with the rate coefficients of propagation kp and termination k t . [2-4] The rate constant of termination k t decreases when the IL concentration and therefore the viscosity of the reaction mixture is increased, whereas the propagation rate coefficient kp increases with increasing IL content. The viscosity of the IL can be varied by either working with mixtures of IL with conventional organic solvents - here the IL [EMIM]EtSO 4 was mixed with DMF - or by variation of the temperature. The influence of the viscosity of the IL ([EMIM]EtS04) on polymerization kinetics of methyl methacrylate (MMA) and styrene/acrylonitrile (S/AN) was investigated.