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(公共法律111-5)资助的。技术摘要：控制合成聚合物中的官能团位置和聚合物主干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。取代二苯乙烯与顺丁烯二酸酐或N-取代马来酰亚胺的交替共聚将成为一条精确控制聚合物主链上官能团位置和密度的大分子合成新途径。空间密集的1，2-二苯乙烷单元与五元环酰亚胺或酸酐单元的结合，得到的结构与约束较少的聚合物链相比预计会相当坚硬。这项研究的合成目标将包括新的空间密集的聚阴离子和聚阳离子，这些阴离子和聚阳离子通过特殊设计和制备的功能二苯乙烯和马来酰亚胺共聚单体的交替共聚，使电荷密度沿链规则变化。将研究空间约束的主链和官能团的放置对基本性质的影响，如持久性、长度和溶液流变性。固体核磁共振将用于研究马来酸酐和马来酰亚胺共聚单体的包结立体化学。硬化型聚阴离子和聚阳离子将与具有相似链状主链的聚两性离子结构进行比较。这些新的聚电解质和多两性离子将通过可控的自由基聚合技术被包裹成双亲水嵌段共聚物(DHBC)。这些DHBC结构将被用来帮助建立治理类似电荷的结构性质关系。在脱氧核糖核酸中观察到的吸引力，以及最近由皮？S实验室报道的由取代的二苯乙烯-α-马来酸酐两性共聚物衍生的合成DHBC中的吸引力。非技术摘要：基于易于缩放和工业实践的自由基聚合化学的新型精确功能化的聚合物材料具有巨大的潜力，将在广泛的先进技术前沿产生实际影响。该方案中描述的基础研究可能会培育出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比表面积网络材料、用于控制水溶液流动的新型刚性聚电解质、可应用于膜的新型聚电解质凝胶以及新型纳米粒子稳定剂。此外，从本研究的新聚合物衍生的新型棒-线圈水嵌段共聚物的合成和研究将提供基本的仿生信息，可能会对各种生物医学应用产生影响，例如治疗给药。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，并以强有力的跨学科模式与其他科学家和工程师互动，以便充分表征和了解这些新的聚合材料的性能。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进行互动，并将指导高分子与界面研究所-S国家科学基金会REU项目的暑期本科生。这一具体的培训对于这些研究人员在对国家的生存和发展至关重要的各种工业和学术领域--S科技企业--开始可行的职业生涯将是有价值的。

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.