Copolymerization metathesis polycondensation chemistry is being pursued to create refined, practical models of high-volume polymers such as low density polyethylene, metallocene polyethylene, and polyvinyl chloride. The objective of this aspect of the research is to better understand polymer structure and thus enhance the performance of the world's largest volume synthetic material (polyolefins). The effort focuses on macromolecular synthesis discovery research, including fundamental exploration of polymer structure.
In addition, different metathesis polymerization strategies will be employed to synthesize a variety of complex polyolefin structures: core/shell nanoparticles using nonaqueous emulsion ADMET chemistry, thin film laminates via solid state metathesis chemistry, nanoblends using dual heterogeneous catalyst systems, precision ionomers/carboxylic acid polymers using tailored diene monomers, and peptide modified polyolefins using melt polymerization techniques. Each of these new materials represents opportunity for discovery; specific applications targeted for them include pro-drug delivery, tissue engineering, high strength ionomers, conductive polymer laminates, and materials offering enhanced gas transport.
NON-TECHNICAL SUMMARY
The common theme for the proposed activity is to improve the behavior of a class of plastics known as polyolefins. During the past 60 years plastics have become a major industry that affects everyone in society from providing better packaging to new textiles to cutting edge technologies found in sophisticated applications such as televisions, cars, computers, and medical devices. In fact, plastics have become the most used synthetic material in the world. This NSF supported research can lead to new plastic materials such as biosensors, lightweight conductors, high strength nanocomposites, even tailored pharmaceuticals. The work will be conducted at the graduate research level in collaboration with major research facilities in the USA (at University of Pennsylvania, Florida State University) as well as the Japan Atomic Energy Agency, and the Max Planck Institute for Polymer Research in Germany.
From an educational perspective, the research will enhance the "Florida Opportunity Scholars" (ROS) program at the University of Florida. This program targets undergraduate students who are the first generation in their families to attend a university and is available when family income is less than $40,000. The goal is to attract these talented yet disadvantaged students into the fields of science and engineering.
The world's most used plastic is called polyethylene and is found everywhere in society, from common household goods to ingenious utility in medicine, such as found in artificial hip joints. It is inexpensive, nontoxic and fairly simple to make. It's importance is signaled by a Chemistry Nobel Prize being awarded in 1963 for the original discovery of one form of polyethylene (many forms exist). No one questions the importance of this material, and while much is known about its chemical makeup, even today - decades after its original discovery - mysteries exist with respect to its ultimate chemical structure. The research done by in this project has addressed several of these mysteries. We have learned more about its crystalline makeup and how such crystallization can influence polyethylene's behavior as a material for use by all of us. Further, we have uncovered a forms of polyethylene crystalline structure that had not been observed before. This new knowledge creates potential opportunity for new applications, both in common day materials as well as in medicine. Considering a broader perspective, this work has served as an excellent tool in providing an educational basis for both undergraduate students and graduate students seeking Masters and PhD degrees in Chemistry. The students who worked on this project have moved on either to professional schools (undergraduates to medicine or graduate school, for example) or graduate students to academic or industrial positions. Further, we have focised on international exchange of undergraduate and graduate students such that we can compete globally in the world of chemical research. The National Science Foundation provides vital support in helping our nation compete globally in science.
