Tailored and Functionalized Polyolefin Structures via Metathesis Polycondensation Chemistry

无环二烯复分解聚合将用于追求4个研究目标：定义支化聚乙烯和相关（官能化）材料的结构性质关系，为组织工程和其他生物应用创建一套“生物烯烃”，探索固态复分解化学，并继续扩大这种复分解导向缩聚化学的催化剂基础。 基于ADMET化学的精密合成技术将用于制备支化聚乙烯，其中分支特性和频率可以以精确的方式控制。 全新的功能化版本的聚乙烯将被制成，这些模型ADMET聚合物的结构/性能关系将被检查。 这样做将为产生有用的官能化聚乙烯结构设定明确的目标。 除了宾夕法尼亚大学和德国的马克斯·普朗克聚合物研究所之外，还与美国的两个工业研究实验室建立了这方面的研究合作。 含有氨基酸和二肽支链的聚烯烃已经通过这种缩合化学制成，聚合物容易结晶，因此使它们成为用于生物医学应用的耐用材料。 将已知的生物活性肽序列连接到聚烯烃主链上将推进这项研究。 这些材料的生物活性将与两个独立的研究小组合作进行研究，一个在佛罗里达大学，另一个在麻省理工学院;这些聚合物中的高阶结构将通过与日本京都大学的合作获得。 迄今为止，固态复分解聚合已经产生了第一个已知的在室温下发生的复分解缩聚化学。 这种简单的聚合物合成方法可能被证明在生成其他难以处理的聚合物结构方面是有用的，其中一些结构在性质上是共轭的。 与佛罗里达大学研究共轭聚合物系统的研究小组就这方面的工作进行了合作。 ADMET化学的催化剂基础将继续处于低水平。 复分解催化剂的研究，这是在世界各地的几个有机金属实验室进行，有利于ADMET化学;在这个项目中所做的复分解催化剂的工作是专门为复分解缩聚量身定制的。聚乙烯是世界上产量最大的塑料，仅在2000年就生产了超过1100亿磅的需求。 它对社会的影响是明显和重要的，因此对聚乙烯和相关材料进行研究可以影响很多人。 这项研究旨在通过理解与这种材料的结晶相关的基本问题，通过合成功能化版本，以及通过扩展到组织工程，药物递送和其他生物医学应用，进一步加强聚乙烯的效用。 氨基酸和肽被附着在塑料的骨架上，以创造这种新的生物材料。 该研究为化学和材料科学的本科生，硕士生和博士生提供了密集的教育和培训基础。 该计划包括与美国、德国和日本的其他研究小组的几项合作。 这些互动将扩大学生的曝光超越佛罗里达大学和我们的国家。

Acyclic diene metathesis polymerization will be employed in the pursuit of 4 research objectives: to define structure property relationships in branched polyethylene and related (functionalized) materials, to create a set of "Bio-Olefins" for tissue engineering and other bioapplications, to explore solid state metathesis chemistry, and to continue to expand the catalyst base for this metathesis oriented polycondensation chemistry. Precision synthesis techniques based on ADMET chemistry will be used to create branched polyethylene, where the branch identity and frequency can be controlled in an exact manner. Completely new functionalized versions of polyethylene will be made, and the structure/property relationships of these model ADMET polymers will be examined. Doing so will set clear goals for the generation of useful functionalized polyethylene structures. Collaborations on this aspect of the research are established with two industrial research laboratories in the USA in addition to the University of Pennsylvania and the Max Planck Institute for Polymer Research in Germany. Polyolefins containing amino acid and dipeptide branches have been made via this condensation chemistry, polymers which readily crystallize thus rendering them as durable materials for biomedical applications. Attaching known biologically active peptide sequences to the polyolefin backbone will advance this research. The biological activity of these materials will be examined in collaboration with two separate research groups, one at the University of Florida and the other at MIT; higher order structures within these polymers will be accessed via collaboration with Kyoto University in Japan. Solid-state metathesis polymerization thus far has produced the first known metathesis polycondensation chemistry occurring at room temperature. This facile method of polymer synthesis may prove useful in generating otherwise intractable polymer structures, some of which are conjugated in nature. Collaborations regarding this aspect of the work are in place with the research group at the University of Florida that investigates conjugated polymer systems. The catalyst base for ADMET chemistry will continue at a low level. Metathesis catalyst research, which is being done in several organometallic laboratories around the world, benefits ADMET chemistry; the metathesis catalyst work done within this project is being tailored especially for metathesis polycondensation.Polyethylene is the largest volume plastic made in the world, with a demand for more than 110 billion pounds produced in the year 2000 alone. Its impact on society is obvious and important, and so conducting research on polyethylene and related materials can influence a large number of people. This research is designed to strengthen the utility of polyethylene further by understanding fundamental issues associated with crystallization of this material, by synthesizing functionalized versions, and by expanding into tissue engineering, drug delivery, and other biomedical applications. Amino acids and peptides are being attached to the backbone of the plastic to create this new class of biomaterials. The research provides an intensive educational and training basis for undergraduate, Masters, and PhD students in chemistry and materials science. Included in the plan are several collaborations with other research groups in the USA, Germany, and Japan. These interactions will broaden the student's exposure beyond the University of Florida and our nation.