NSF-CGP Science Fellowship Program: Control of Solute Permeability Across Membranes Made of Di/Triblock Copolyelectrolytes.

9311941瓦拉纳西该奖项将支持俄亥俄州托莱多大学化学工程系萨西达尔·瓦拉纳西教授在美国国家科学基金会-全球伙伴关系中心科学奖学金计划下15个月的资助。瓦拉纳西教授将与日本筑波国家材料与化学研究所(NIMC)有机材料系Norihiko Minoura博士进行为期三个月的合作研究项目。这项研究的重点是控制由双/三嵌段共聚电解质制成的膜的溶质渗透性。这将通过制备膜来实现，通过改变沐浴在膜上的溶液的pH和/或离子强度，可以以可预测的方式调节膜对大布朗溶质的渗透性。反过来，这种能力应该使人们能够使膜在分离两种大小仅有很小差异的溶质时具有高度的选择性。为了实现这一目标，将完善两种膜。首先，将聚电解质吸附在非选择性微孔膜中。第二种是用溶剂浇铸成膜的ABA型三嵌段共聚肽。通过比较微相分离法和微孔膜接枝共聚物法制备的膜的性能特征，以确定哪种方法能获得可靠和坚固的膜，并具有可调的渗透性能。研究结果在多种重要领域具有实际应用的潜力，如药物的自我调节释放和几种生物化学物质的合成。国家材料和化学研究所是一流的设施，在聚合物材料研究方面取得了长足的进步。米努拉博士是膜科学领域的知名专家，尤其是合成聚电解质膜。这种专业化，加上瓦拉纳西教授在该领域的专门知识，应能提供一种极好的协作，这种协作很可能在今后以非正式的方式继续下去。

9311941 Varanasi This award will support a fifteen month grant under the NSF-CGP (Center for Global Partnership) Science Fellowship Program for Professor Sasidhar Varanasi, Department of Chemical Engineering, University of Toledo, Ohio. Professor Varanasi will undertake a three month cooperative research project with Dr. Norihiko Minoura, Department of Organic Materials, National Institute of Materials and Chemical Research (NIMC) in Tsukuba, Japan. The research will focus on the control of solute permeability across membranes made of di/triblock copolyelectrolytes. This will be accomplished by fabricating membranes, the permeability of which to large Brownian solutes can be tuned in a predictable manner, via changing the pH and/or ionic strength of the solutions bathing the membrane. This ability, in turn, should allow one to make the membrane highly selective in separating two solutes the sizes of which differ only to a small extent. Two kinds of membranes will be perfected to achieve the goal. First, will be polyelectrolytes absorbed in the pores of non-selective microporous membranes. The second would be ABA type triblock copolypeptides cast into a film using a solvent. The performance characteristics of membranes made by microphase separation will be compared to those made via grafting copolymers into microporous membranes to determine which of the methods leads to reliable and robust membranes with "tunable" permeation properties. Results of the research have potential for practical applications in a variety of important fields such as self-regulated release of pharmaceutics and the synthesis of several biochemicals. The National Institute of Materials and Chemical Research is a first- rate facility that has made considerable progress in polymeric materials research. Dr. Minoura is a well-known expert in membrane science in general and in synthetic polyelectrolyte membranes in particular. This specialization coupled with Professor Va ranasi's expertise in the area should provide an excellent collaboration that most likely would continue on an informal basis in the future.