Precision Polyolefins Embracing Tacticity, Amorphous Structure Control, and Precision-Enhanced Biological Activity

精密聚烯烃具有立构性、无定形结构控制和精密增强的生物活性

• 批准号: 1203136
• 负责人: K. Wagener
• 金额: $ 30.01万
• 依托单位: University of Florida
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-07-01 至 2015-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1203136&HistoricalAwards=false
• 关键词: Precision; Polyolefins; Embracing; Tacticity; Amorphous

TECHNICAL SUMMARY:Tactic versions of precision polyolefin materials are being prepared to define the importance of proximity of precisely placed chiral centers in a linear polymer chain. The chain-length distance between these chiral centers is of special interest. Crystallization will be examined in detail via variable temperature X-ray techniques and thermal analysis. The precision work will be extended to a systematic study of commercially prepared metallocene-generated polyethylene, since it is now possible to space branches as far apart as 75 carbons. Long-chain alkyl branches will be precisely attached far apart from each other, and the morphological structure of these materials will be explored.The morphology of highly interactive structures, including those possessing ionic liquid entities, will be elucidated as well. Preliminary research suggests that ionic liquid entities, when placed precisely in the polymer backbone, lead to enormous inter-chain interaction in these materials. A detailed study of performance (tensile strength, shear thickening, etc.) as a function of counterion identity comprises a major part of this work. The research will be done in collaboration with expert morphology research groups in the USA, Germany, and Japan.Finally, the PI will synthesize water-soluble versions of these precision materials. Potential uses for water-soluble polymers are quite large. Of particular interest will be a study of ion binding in these water-soluble macromolecules. The research will begin using precision linear copolymers possessing both in-chain and grafted poly(oxyethylene) in varying amounts. The biological activity of these materials, particularly in terms of chiral response, will be measured as well.NON-TECHNICAL SUMMARY:Better understanding of the behavior of the world's largest-volume plastic, polyethylene, comprises a major theme in this research. The PI and his group will prepare polyethylene analogues whose molecules contain branches at regular intervals, thus creating materials with precisely defined architectures. The properties of these materials will be studied with a variety of techniques. The research itself serves as an educational tool at both the undergraduate and graduate level, where the impact of interacting young scientists from a variety of countries is important. For example, a "Research Abroad for Graduate Students" program has been established to give students global exposure. Included are interactions created by government institutions (such as found in Germany at the Max Planck Institute for Polymer Research). Further, the PI will continue to seek and educate undergraduate students who are in the "Florida Opportunity Scholars Program" and who are the first in their families to go to college.

技术总结：正在制备精密聚烯烃材料的战术版本，以确定线性聚合物链中精确放置的手性中心接近的重要性。这些手性中心之间的链长距离是特别感兴趣的。结晶将通过变温X射线技术和热分析进行详细检查。这项精密的工作将扩展到对商业化制备的聚烯烃生成的聚乙烯的系统研究，因为现在可以将分支的间距扩展到75个碳原子。长链烷基支链将精确地彼此远离地连接，并且这些材料的形态结构将被探索。高度相互作用的结构的形态，包括那些具有离子液体实体的结构，也将被阐明。初步研究表明，离子液体实体，当被精确地放置在聚合物主链中时，导致这些材料中巨大的链间相互作用。详细的性能研究（拉伸强度、剪切增稠等）作为一个国家身份的功能包括这项工作的主要部分。这项研究将与美国、德国和日本的形态学专家研究小组合作完成。最后，PI将合成这些精密材料的水溶性版本。水溶性聚合物的潜在用途相当大。特别感兴趣的是对这些水溶性大分子中离子结合的研究。这项研究将开始使用精确的线性共聚物，同时拥有链内和接枝聚（环氧乙烷）在不同的数量。这些材料的生物活性，特别是在手性反应方面，也将被测量。非技术性总结：更好地了解世界上最大体积的塑料聚乙烯的行为，是本研究的一个主要主题。PI和他的团队将制备聚乙烯类似物，其分子以规则的间隔包含分支，从而创造具有精确定义结构的材料。 这些材料的特性将用各种技术进行研究。 这项研究本身是本科生和研究生阶段的教育工具，来自不同国家的年轻科学家的互动影响很重要。例如，设立了一个“研究生出国研究”方案，让学生接触全球。 包括政府机构创造的相互作用（例如在德国的马克斯普朗克聚合物研究所发现的）。此外，PI将继续寻求和教育本科生谁是在“佛罗里达机会学者计划”，谁是第一个在他们的家庭去上大学。