Precisely Functionalized Alternating Copolymers Based on Substituted Stilbene Monomers

ARRA声明：该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。技术总结：控制合成聚合物中官能团位置和聚合物主链结构的能力对于理解基本结构性质关系以及设计具有重要性能特征的聚合物材料非常重要。 取代苯乙烯与马来酸酐或N-取代马来酰亚胺的交替共聚合将作为一种新的途径进行研究，以合成高分子，精确控制官能团的位置和密度沿聚合物主链沿着。空间拥挤的1，2-二苯基乙烷单元与五元环状酰亚胺或酸酐单元的结合导致预期当与较少约束的聚合物链相比时显著变硬的结构。本研究的合成目标将包括新的空间拥挤的聚阴离子和聚阳离子的电荷密度沿着链的交替共聚，使专门设计和制备的功能性苯乙烯和马来酰亚胺共聚单体的定期变化。 将研究空间受限的主链和官能团的位置对基本性质如持久性长度和溶液流变性质的影响。固态核磁共振将用于研究马来酸酐和马来酰亚胺共聚单体的链立体化学。 硬化的聚阴离子和聚阳离子将与具有相似链骨架的聚两性离子结构进行比较。这些新型的聚电解质和聚两性离子将通过可控自由基聚合技术被连接成双亲水性嵌段共聚物（DHBC）。 这些DHBC结构将被用来帮助建立结构属性关系，管理？同类指控在DNA中观察到的吸引力以及PI最近的报告？非技术概要：新的精确功能化的聚合物材料，基于容易放大和工业实践的自由基聚合化学，具有跨越广泛的先进技术前沿的实际影响的巨大潜力。 该提案中描述的基础研究可以促进一种新的聚合物平台，该平台有可能用于生产用于储氢的新型多孔和高表面积网络材料，用于控制水性流体中流动的新型刚性聚电解质，可用于膜的新型凝胶，以及新型纳米颗粒稳定剂。 此外，从本研究的新聚合物衍生的新棒-线圈水性嵌段共聚物的合成和研究将提供基本的仿生信息，这些信息可以在各种生物医学应用中产生影响，例如治疗递送。 积极参与研究项目将要求研究生掌握现代聚合和合成化学，并以强大的跨学科模式与其他科学家和工程师互动，以充分表征和了解这些新聚合物材料的特性。参与这项研究的研究生将与弗吉尼亚理工大学聚合物短期课程的工业研究人员互动，并将指导高分子和界面研究所的暑期本科生。美国国家科学基金会REU计划。 这种具体的培训将是有价值的启动可行的职业生涯，为这些研究人员在各种工业和学术领域的重要维持和发展的国家？的科技企业。

ARRA STATEMENT:This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).TECHNICAL SUMMARY:The ability to control functional group placement and polymer backbone structure in synthetic polymers is important for understanding fundamental structure property relationships as well as designing polymeric materials with important performance characteristics. The alternating copolymerization of substituted stilbenes and maleic anhydride or N-substituted maleimides will be studied as a new route to synthesize macromolecules with precise control of the placement and density of functional groups along the polymer backbone. The incorporation of the sterically crowded 1,2-diphenylethane units, in conjunction with the five member cyclic imide or anhydride units, results in structures that are anticipated to be considerably stiffened when compared to less constrained polymer chains. Synthetic targets of this research will include new sterically crowded polyanions and polycations with a regular variation of charge densities along the chain enabled by the alternating copolymerization of specifically designed and prepared functional stilbenes and maleimide comonomers. The consequences of the sterically constrained backbones and placement of functional groups on fundamental properties such as persistence length and solution rheological properties will be studied. Solid state NMR will be used to study the enchainment stereochemistry of the maleic anhydride and maleimide comonomers. The stiffened polyanions and polycations will be compared to polyzwitterionic structures with similar chain backbones. These new polyelectrolytes and polyzwitterions will be enchained into double hydrophilic block copolymers (DHBC) by controlled free radical polymerization techniques. These DHBC structures will be used to assist in establishing structure property relationships that govern the ?like-charge? attraction observed in DNA and more recently reported from the PI?s laboratory in a synthetic DHBC derived from a substituted stilbene-alt-maleic anhydride zwitterionic copolymer.NON-TECHNICAL SUMMARY:New precisely functionalized polymeric materials, based on easily scaleable and industrially practiced free radical polymerization chemistries have significant potential to have practical impact across a broad range of advanced technology frontiers. The fundamental research described in this proposal could foster a new polymer platform which has the potential to be used to produce new porous and high surface area network materials for hydrogen storage, new rigid polyelectrolytes for control of flow in aqueous fluids, new polyelectrolyte gels which could be applied in membranes, and new nano-particle stabilization agents. In addition the synthesis and study of new rod-coil aqueous block copolymers, derived from the new polymers of this study, will provide fundamental biomimetic information that can have impact in various biomedical applications such as therapeutic delivery. Active participation in the research project will require graduate students to master modern polymerization and synthetic chemistries and to interact with other scientists and engineers in a strong interdisciplinary mode in order to fully characterize and understand the properties of these new polymeric materials. The graduate students involved with this research will interact with industrial researchers in Virginia Tech polymer short courses and will mentor summer undergraduate students in the Macromolecules and Interfaces Institute?s NSF REU program. This specific training will be valuable for initiating viable careers for these researchers in a variety of industrial and academic areas important for sustaining and growing the nation?s science and technology enterprise.