Effects of Trace Water on Self-Assembly of Sulfonated Block Copolymers During Solution Processing
Effects of Trace Water on Self-Assembly of Sulfonated Block Copolymers During Solution Processing
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溶液加工过程中微量水对磺化嵌段共聚物自组装的影响
DOI：
10.1021/acsapm.0c00806
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发表时间：
2020
影响因子：
5
通讯作者：
Stein, Gila E.
中科院分区：
文献类型：
--
作者：
Madathil, Karthika;Lantz, Kayla A.;Stefik, Morgan;Stein, Gila E.
研究了磺化嵌段共聚物的溶液浇铸膜在水净化、气体分离和燃料电池中的应用。众所周知，溶剂组成影响磺化嵌段共聚物溶液和相应膜中形成的结构。由于磺酸化聚合物的吸湿性质，溶液通常含有微量水，并且微量水对结构形成的影响之前尚未探索过。水将驱动磺酸的解离，这反过来可能通过破坏酸基团之间的氢键来加速聚合物链的重排。在这项工作中，我们研究了微量水的磺化五嵌段共聚物（SPC）的溶液状态的结构和最终的膜形态，使用小角X-射线散射的影响。使用的溶剂是甲苯和正丙醇的混合物，其中水与磺酸的摩尔比（λ）不同。在λ = 0的溶液中，SPC采用无序结构。向SPC溶液中添加微量水（λ = 3.2）驱动快速自组装成有序的层状结构。然而，溶液中微量水的存在对将SPC加工成膜几乎没有影响，因为水在干燥环境中将迅速从干燥膜中逸出。对于薄膜处理，环境湿度比溶液中的微量水更重要，因为随着溶剂蒸发，空气中的水分为薄膜提供了恒定的水供应。虽然有许多变量控制溶液浇铸SPC膜的形态，但这些研究表明，微量的水在溶液状态自组装的动力学和热力学以及膜干燥过程中纳米级结构的演变中起着关键作用。
Solution-cast films of sulfonated block copolymers are investigated for applications in water purification, gas separations, and fuel cells. It is well known that solvent composition influences the structures that form in solutions of sulfonated block copolymers and in the corresponding films. The solutions often contain trace water due to the hygroscopic nature of sulfonated polymers, and the effect of trace water on structure formation has not been previously explored. Water will drive dissociation of sulfonic acid, which in turn might accelerate the rearrangement of polymer chains by disrupting hydrogen bonds between acid groups. In this work, we examine the effects of trace water on the solution-state structure of a sulfonated pentablock copolymer (SPC) and the ultimate film morphology using small-angle X-ray scattering. The solvent used was a mixture of toluene andn-propanol with varying molar ratios of water to sulfonic acid (λ). In solutions with λ = 0, the SPC adopts a disordered structure. The addition of trace water (λ = 3.2) to SPC solutions drives a rapid self-assembly into an ordered lamellar structure. However, the presence of trace water in the solution has little effect on processing the SPC into films as water will rapidly escape from the drying film in a dry environment. For film processing, ambient humidity is more important than trace water in the solution as moisture in air provides a constant supply of water to the film as the solvent evaporates. While there are many variables that control the morphology of solution-cast SPC films, these studies demonstrate that trace amounts of water play a critical role in kinetics and thermodynamics of solution-state self-assembly and the evolution of nanoscale structures during film drying.
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溶剂可调多嵌段离聚物形态及其与模量、水膨胀、方向依赖性离子传输和执行器性能的关系
影响因子：
4.6
作者：
Wenjian Zheng;C. Cornelius
通讯作者：
C. Cornelius
预测二元溶剂混合物中磺化五嵌段共聚物的溶液形态
DOI：
10.1002/polb.23914
发表时间：
2015
期刊：
Journal of Polymer Science Part B
影响因子：
--
作者：
Philip J. Griffin;Grace B. Salmon;Jamie T Ford;K. Winey
通讯作者：
K. Winey
离聚物溶液到薄膜的固化取决于溶剂类型及其对形态和离子传输的影响
影响因子：
6
作者：
Donghui Wang;Yanfang Fan;Mingqiang Zhang;R. Moore;C. Cornelius
通讯作者：
C. Cornelius
影响因子：
4.6
作者：
Mineart, Kenneth P.;Jiang, Xi;Spontak, Richard J.
通讯作者：
Spontak, Richard J.
影响因子：
9.5
作者：
Elisabeth R. Thomas;Amit Jain;Stewart C. Mann;Yi Yang;Matthew D. Green;W. Walker;F. Perreault;Mary Laura Lind;R. Verduzco
通讯作者：
Elisabeth R. Thomas;Amit Jain;Stewart C. Mann;Yi Yang;Matthew D. Green;W. Walker;F. Perreault;Mary Laura Lind;R. Verduzco