Synthesis and kinetics of polymerization of hydrophilic monomers: 2,3-dihydroxypropylacrylate and 2,3-dihydroxypropylmethacrylate
Synthesis and kinetics of polymerization of hydrophilic monomers: 2,3-dihydroxypropylacrylate and 2,3-dihydroxypropylmethacrylate
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亲水性单体丙烯酸2,3-二羟丙酯和甲基丙烯酸2,3-二羟丙酯的合成及聚合动力学
DOI：
10.1002/pola.1162
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发表时间：
2001
期刊：
影响因子：
--
通讯作者：
P. Calle
中科院分区：
文献类型：
--
作者：
F. García;J. L. Peña;J. Delgado;N. García;J. Guzmán;E. Riande;P. Calle
甘油(1，2，3-三羟基丙烷)与丙烯酸和甲基丙烯酰氯反应，得到了不含羟基、含一个羟基或含两个羟基的不饱和单体。将不同单体的摩尔分数的实验值与考虑涉及两个或七个动力学常数的不同机理得到的理论值进行了比较。只有假设羟基的反应性随着取代基的存在而改变，理论和实验结果才能达到一致。研究了甲基丙烯酸二羟丙酯(GA)和甲基丙烯酸2，3-二羟基丙酯(GM)在水-二氧六环溶液中不同温度下的自由基聚合反应。用紫外光谱技术测定了反应的动力学常数，并与相同条件下测得的甲基丙烯酸甲酯、甲基丙烯酸甲酯、甲基丙烯酸羟乙酯和甲基丙烯酸羟乙酯的结果进行了比较。在50~65°C温度范围内，甲基丙烯酸单体GM的Kp/kt1/2值大于0.5L1/2mol−1/2 S−1/2，超过了丙烯酸单体GA的2L1/2moL−1/2 S−1/2，可能是已报道的此类单体的最高值。用电子顺磁共振波谱研究了GM的聚合反应。所有聚合物在反应混合物中都是可溶的，直到非常高的转化率，并且当单体浓度等于或低于1摩尔L−1时，从未检测到凝胶效应。
Unsaturated monomers containing none, one, or two hydroxyl groups were obtained by the reaction of glycerol (1,2,3-trihydroxypropane) with acrylic and methacrylic chloride. The experimental values of the mole fractions of the different monomers were compared with those theoretically obtained by considering different mechanisms involving two or seven kinetic constants. Agreement between the theoretical and experimental results could only be achieved by assuming that the reactivity of the hydroxyl groups changed with the presence of the substituents. The investigation of the radical polymerizations 2,3-dihydroxypropylacrylate (GA) and 2,3-dihydroxypro- pylmethacrylate (GM) was carried out at several temperatures in water–dioxane solutions. Ultraviolet spectroscopic techniques were used to determine the kinetic constants, and the results were compared with those obtained in the same conditions for methyl acrylate, methyl methacrylate, 2-hydroxyethylacrylate, and 2-hydroxyethylmethacrylate. The values of the ratio kp/kt1/2 for the methacrylic monomer GM were higher than 0.5 L1/2 mol−1/2 s−1/2 at temperatures between 50 and 65 °C. These values exceeded 2 L1/2 mol−1/2 s−1/2 for the acrylic monomer GA, perhaps the highest values reported for this kind of monomer. Electron paramagnetic resonance spectroscopy was also used to study the polymerization of GM. All the polymers were soluble in the reaction mixture until very high conversions, and the gel effect was never detected at monomer concentrations equal to or lower than 1 mol L−1. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 1843–1853, 2001