Enzyme-mediated radical initiation of acrylamide polymerization:: main characteristics of molecular weight control
Enzyme-mediated radical initiation of acrylamide polymerization:: main characteristics of molecular weight control
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DOI：
10.1016/s0032-3861(01)00041-6
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发表时间：
2001-06-01
期刊：
影响因子：
4.6
通讯作者：
Maréchal, E
中科院分区：
文献类型：
--
作者：
Durand, A;Lalot, T;Maréchal, E
研究了辣根过氧化物酶催化氧化还原体系(过氧化氢/β-二酮)引发的丙烯酰胺自由基聚合，重点研究了聚合物的相对分子质量的控制。特别考察了2，3-戊二酮(Acac)作为β-二酮的情况。结果表明，ACAC的浓度和酶的浓度很容易控制聚合物的相对分子质量。过氧化氢的浓度不会在很大程度上影响分子量，除非在酶降解或副反应干扰正常酶循环的极端情况下。由P-二酮的化学结构变化引起的分子量变化归因于对酶循环的反应性。用经典的自由基聚合动力学方程和酶催化的具体表达式对实验结果进行了合理化。理论表达式所显示的趋势解释了实验结果所给出的演化。(C)2001爱思唯尔科学有限公司。保留所有权利。
The free-radical polymerization of acrylamide initiated by a redox system (hydrogen peroxide/beta -diketone) catalyzed by horseradish peroxidase is studied with emphasis on the control of the molecular weight of the polymer. The case where 2,3-pentanedione (Acac) is used as the beta -diketone is particularly examined. It is shown that the concentration of Acac and that of the enzyme readily control the molecular weight of the polymer. The concentration of hydrogen peroxide does not influence the molecular weight to a significant extent except at extreme values for which enzyme degradation or side reactions interfere with the normal enzymatic cycle. The variations of the molecular weight induced by changes in the chemical structure: of the P-diketone are attributed to the reactivity toward the enzymatic cycle. The experimental results are rationalized by the use of classical kinetic equations for free-radical polymerization and including the specific expressions of enzymatic catalysis. The tendencies indicated by the theoretical expressions account for the evolutions given by the experimental results. (C) 2001 Elsevier Science Ltd. All rights reserved.