Gelation in Photoinduced ATRP with Tuned Dispersity of the Primary Chains.
Gelation in Photoinduced ATRP with Tuned Dispersity of the Primary Chains.
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DOI：
10.1021/acs.macromol.2c02159
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发表时间：
2023-03-14
期刊：
影响因子：
5.5
通讯作者：
Kopec, Maciej
中科院分区：
文献类型：
--
作者：
Dawson, Frances;Jafari, Hugo;Rimkevicius, Vytenis;Kopec, Maciej
我们研究了光诱导原子转移自由基聚合（ATRP）中的凝胶化作为铜催化剂负载量的函数，从而主链分散性。使用平行聚合的丙烯酸甲酯与和不添加的二乙烯基交联剂（1，6-己二醇二丙烯酸酯），在初始凝胶化的分子量和主链的分散性的近似值得到。根据Flory-Stockmayer理论，当主链的分散性增加同时保持恒定的单体/引发剂/交联剂比率时，实验凝胶化发生在逐渐降低的转化率下。然后使用分散性和引发效率的测量实验值计算理论凝胶点。对ATRP的Flory-Stockmayer方程进行了经验修正，从而更准确地预测了凝胶点。研究发现，增加主链的分散度不会影响理论凝胶点和实验凝胶点之间的距离，从而不会影响分子内环化的程度。此外，网络的机械性能，如平衡溶胀比和剪切储能模量，表现出很小的变化与催化剂负载量，主要取决于交联密度。
We investigated gelation in photoinduced atom transfer radical polymerization (ATRP) as a function of Cu catalyst loading and thus primary chain dispersity. Using parallel polymerizations of methyl acrylate with and without the addition of a divinyl crosslinker (1,6-hexanediol diacrylate), the approximate values of molecular weights and dispersities of the primary chains at incipient gelation were obtained. In accordance with the Flory–Stockmayer theory, experimental gelation occurred at gradually lower conversions when the dispersity of the primary chains increased while maintaining a constant monomer/initiator/crosslinker ratio. Theoretical gel points were then calculated using the measured experimental values of dispersity and initiation efficiency. An empirical modification to the Flory–Stockmayer equation for ATRP was implemented, resulting in more accurate predictions of the gel point. Increasing the dispersity of the primary chains was found not to affect the distance between the theoretical and experimental gel points and hence the extent of intramolecular cyclization. Furthermore, the mechanical properties of the networks, such as equilibrium swelling ratio and shear storage modulus showed little variation with catalyst loading and depended primarily on the crosslinking density.
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DOI：
10.1002/advs.202003701
发表时间：
2021-03
期刊：
Advanced science (Weinheim, Baden-Wurttemberg, Germany)
影响因子：
--
作者：
Bagheri A;Fellows CM;Boyer C
通讯作者：
Boyer C
影响因子：
5.5
作者：
Li, Wenwen;Gao, Haifeng;Matyjaszewski, Krzysztof
通讯作者：
Matyjaszewski, Krzysztof
影响因子：
3.4
作者：
Rolland, Manon;Lohmann, Victoria;Anastasaki, Athina
通讯作者：
Anastasaki, Athina
影响因子：
5.5
作者：
Gao, Haifeng;Min, Ke;Matyjaszewski, Krzysztof
通讯作者：
Matyjaszewski, Krzysztof
影响因子：
5.5
作者：
Mann, Joseph L.;Rossi, Rachel L.;Appel, Eric A.
通讯作者：
Appel, Eric A.