Continuous Free‐Radical Polymerization with Long‐Chain Branching and Scission in a Tanks‐in‐Series Model
Continuous Free‐Radical Polymerization with Long‐Chain Branching and Scission in a Tanks‐in‐Series Model
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DOI：
10.1002/mats.201300148
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发表时间：
2014-03
影响因子：
1.4
通讯作者：
H. Tobita
中科院分区：
文献类型：
--
作者：
H. Tobita
涉及聚合物转移反应的自由基聚合，导致长链支化和断裂，如在高压乙烯聚合的情况下，被认为是一个罐在串联模型。在串联罐模型中，停留时间分布（RTD）变得更窄，接近活塞流反应器（PFR）的停留时间分布，因为罐的数量N增加。随着N值的增加，分子量分布相当快地接近PFR的分子量分布。另一方面，高度支化的聚合物的支化密度和回转半径可以显示出与PFR的明显差异，即使当N值大至20时。目前的理论方法将提供很大的洞察连续生产过程具有复杂的RTD。
Free-radical polymerization that involves the polymer transfer reactions, leading to both long-chain branching and scission, as in the cases of high-pressure ethylene polymerization, is considered for a tanks-in-series model. In a tanks-in-series model, the residence time distribution (RTD) becomes narrower to approach that for a plug flow reactor (PFR), as the number of tanks, N increases. The molecular weight distribution approaches rather quickly to that for a PFR, as the N-value increases. On the other hand, the branching density and the radius of gyration of highly branched polymers may show clear differences from that for a PFR, even when N-value is as large as 20. The present theoretical approach would provide great insight into the continuous production processes having complex RTDs.