Membranes Based on Polymers with Long Alkyl Side-Chains

摘要建议编号：9714305建议类型：调查员发起首席调查员：唐纳德·R·保罗隶属关系：德克萨斯大学奥斯汀分校这项拨款是通过化学和运输系统司界面、运输和分离计划的分离和净化计划子要素授予的。首席研究员是德克萨斯大学奥斯汀分校的唐纳德·保罗博士。这项研究旨在开发具有温度引起的渗透性变化的膜材料。这是一种新的方法，其中渗透率不是温度的平稳增加函数，而是一种微小的温度变化可以作为渗透率大幅变化的开关的情况。这些温度诱导的渗透性开关是通过使用含有烷基侧链的聚合物来实现的，烷基侧链的结晶相对独立于聚合物主链。当材料被加热到超过侧链的玻璃化转变温度时，结晶度的损失打开了运输通道，增加了渗透性。从可渗透膜到相对不透膜的转变发生在侧链的玻璃化转变温度上。这种温度感应型磁导率开关有几个重要的应用。其中最有趣的是利用温度的季节性变化来释放农药和化肥等农业制剂的可能性。当这些药物被放置在由这些聚合物材料制成的胶囊中时，温度开关也可以用来输送药物。这里提出的概念代表了聚合物膜研究的前沿领域。

Abstract Proposal No: 9714305 Proposal Type: Investigator Initiated Principal Investigator: Donald R. Paul Affiliation: University of Texas at Austin This grant is awarded through the Separations and Purification Program sub-element of the Interfacial, Transport and Separations Program of the Chemical and Transport Systems Division. The principal investigator is Dr. Donald Paul at the University of Texas at Austin. The research is directed at the development of membrane materials that have temperature induced changes in permeability. This is a novel approach where the permeability is not a smoothly increasing function of temperature but a rather a situation where a small temperature change can serve as a switch for substantial permeability changes. These temperature induced switches in permeability are brought about by the use of polymers containing alkyl side chain that crystallize relatively independent of the polymer backbone. When the material is heated up beyond the glass transition temperature of the side chains, the loss of crystallinity opens up transport pathways and increases the permeability. The switch from a permeable to a relatively nonpermeable membrane occurs across the glass transition temperature of the side chains. There are several significant applications of such temperature induced permeability switches. Amongst the most interesting is the potential to use seasonal changes in temperature to release agricultural agents such as pesticides of fertilizers. The temperature switches can also be used to deliver drugs when these drugs are placed in capsules make from these polymeric materials. The concepts presented here represent frontier areas of polymer membrane research.