Reaction kinetics of polymeric reagents
Reaction kinetics of polymeric reagents
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聚合物试剂的反应动力学
DOI：
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发表时间：
1985
期刊：
影响因子：
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通讯作者：
H. Morawetz
中科院分区：
文献类型：
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作者：
H. Morawetz
通过对含聚合物体系中反应动力学的研究，发现：(1)在稀溶液中，偶氮苯残基的热异构化和光化学异构化不会因其进入聚合物骨架而受到阻碍。在玻璃态下，聚合物侧链或主链上的偶氮苯残基的异构化反应动力学反映了自由体积和体积松弛的分布。(2)聚合物与低分子试剂的反应可能受到邻基效应和聚合物主链对其微环境极性贡献的影响。(3)酶对聚合物侧链的攻击强烈地依赖于敏感键与主链的间距。(4)在两个柔性链分子之间的反应中没有观察到预期的“动力学排斥体积效应”。(5)连接到膨胀的交联凝胶上的基团的反应可能反映了局部极性的空间变化。(6)水溶性试剂对乳胶粒的侵袭可能仅限于乳胶粒表面。(7)多离子的存在对涉及两个小离子物种的反应产生不同的影响。
Kinetic studies of reactions in systems containing polymers have led to the following observations: (1) In dilute solution the thermal and the photochemical isomerization of azobenzene residues is not impeded by their incorporation into a polymer backbone. In the glassy state, the kinetics of the isomerization of azobenzene residues in polymer side chains or backbones reflect the distribution of free volume and volume relaxation. (2) Reactions of polymers with low molecular weight reagents may be affected by neighboring group effects and by the contribution of the polymer backbone to the polarity of its microenvironment. (3) Attack of an enzyme on a polymer side chain depends sharply on the spacing of the susceptible bond from the chain backbone. (4) The expected “kinetic excluded volume effect” in reactions between two flexible chain molecules was not observed. (5) Reactions involving groups attached to a swollen crosslinked gel may reflect spatial variations of the local polarity. (6) Attack of water-soluble reagents on latex particles may be restricted to the surface of the particle. (7) The presence of a polyion exerts various effects on reactions involving two small ionic species.