Associating Polymers in the Strong Interaction Regime: Validation of the Bond Lifetime Renormalization Model
Associating Polymers in the Strong Interaction Regime: Validation of the Bond Lifetime Renormalization Model
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DOI：
10.1021/acs.macromol.2c02446
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发表时间：
2023-03-10
期刊：
影响因子：
5.5
通讯作者：
Sokolov, Alexei P.
中科院分区：
文献类型：
--
作者：
Ge, Sirui;Carden, Gregory Peyton;Sokolov, Alexei P.
对缔合聚合物的动力学和粘弹性特性的定量理解仍然是一个挑战。本研究详细分析了具有两个不同端基（形成多个氢键的脲和形成较弱氢键的羧酸）功能化的遥爪 PDMS 的介电和流变数据。结果分析表明，在强键合脲官能化样品的情况下，键解离和键重排时间相似，但在相互作用较弱的羧酸端基的情况下则不同。我们证明这些结果与键寿命重整化模型的预测非常吻合。所提出的结果表明，流变数据仅可用于估计强相互作用状态下键解离的活化能，并且至少在本文研究的系统中，在这些估计中应明确考虑片段弛豫。
Quantitative understanding of dynamics and viscoelastic properties of associating polymers remains a challenge. This study presents detailed analysis of dielectric and rheological data for telechelic PDMS functionalized with two different end groups, urea that forms multiple hydrogen bonds and carboxylic acid that forms much weaker hydrogen bonds. Analysis of the results revealed that the bond dissociation and bond rearrangement times are similar in the case of strong bonding urea-functionalized samples but are different in the case of weaker interacting carboxylic acid end groups. We demonstrate that these results agree well with the predictions of the bond lifetime renormalization model. The presented results suggest that rheological data can be used for the estimation of activation energy for bond dissociation only in the strong interaction regime and that segmental relaxation should be explicitly accounted for in these estimates, at least, in the systems studied herein.