A general model for the ideal chain length distributions of polymers made with reversible deactivation
A general model for the ideal chain length distributions of polymers made with reversible deactivation
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DOI：
10.1039/d1py01331a
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发表时间：
2022-01-07
影响因子：
4.6
通讯作者：
Konkolewicz, Dominik
中科院分区：
文献类型：
--
作者：
Kearns, Madison M.;Morley, Colleen N.;Konkolewicz, Dominik
聚合物分子量或链长分布是聚合物体系的核心特征，其分布与聚合物材料的性质和性能密切相关。利用链端的可逆活化/失活，将单体添加到链端的活性形式，建立了聚合物的理想分布模型。理想的分配集中在生命链上，系统不可逆的终止或转移对系统的影响最小。该模型适用于ATRP、RAFT和阳离子聚合，也可用于描述复杂体系，如共混聚合物和嵌段共聚物。该模型可以很容易和准确地拟合分子量分布，给出增殖与失活的比率，以及聚合条件下链被激活/失活的平均次数。否则，很难从转化数据或分子量分布来评估每条链的平均活化周期数。由于该模型可以应用于广泛的聚合，提供有关潜在聚合过程的有用信息，它可以用来提供大分子合成和反应结果的基本见解。
Polymer molecular weight, or chain length distributions, are a core characteristic of a polymer system, with the distribution being intimately tied to the properties and performance of the polymer material. A model is developed for the ideal distribution of polymers made using reversible activation/deactivation of chain ends, with monomer added to the active form of the chain end. The ideal distribution focuses on living chains, with the system having minimal impact from irreversible termination or transfer. This model was applied to ATRP, RAFT, and cationic polymerizations, and was also used to describe complex systems such as blended polymers and block copolymers. The model can easily and accurately be fitted to molecular weight distributions, giving information on the ratio of propagation to deactivation, as well as the mean number of times a chain is activated/deactivated under the polymerization conditions. The mean number of activation cycles per chain is otherwise difficult to assess from conversion data or molecular weight distributions. Since this model can be applied to wide range of polymerizations, giving useful information on the underlying polymerization process, it can be used to give fundamental insights into macromolecular synthesis and reaction outcomes.