Theory of Polymer Crystallization

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Nontechnical SummaryMost of the materials today are made from polymers constituting a multi-billion-dollar industry. Whether we think about plastic cups, packaging materials, high-performance nano- and micro-devices, clothing materials, or aircraft parts, these are fabricated through polymeric chains. An understanding of how to control organization of polymers into desirable structures under a variety of externally imposed conditions is currently missing. However, such an understanding is vital to promulgate design rules for making new materials as well as for improving the performance of the materials available today. The proposed research will contribute to the understanding of polymer crystallization in terms of both kinetic pathways and the emergence of the ordered structures. This proposal is aimed at building new conceptual models and discovering new laws of polymer crystallization. In addition, the proposed theoretical work complements many experimental efforts being actively pursued worldwide.The results of the proposed research will have impact in numerous applied areas such as polymer processing, and fabrication of polymeric nanomaterials. Training of graduate students in this challenging research area is the strong educational component of this proposal.Technical SummaryCrystallization of polymers is full of intrigue and a fundamental understanding of how polymer chains organize into hierarchical structures continues to be elusive. Using advanced theoretical and computational tools to account for the unique attribute of the conformational entropy and topological defects in cooperation with enthalpic driving forces for assembly this proposal addresses (a) single crystal morphology and relative stabilities of flat lamellae, hollow pyramids, bowls, scrolls, and twisted lamellae, (b) kinetics of melting, and (c) origin of melt-memory. This proposal is aimed at building new conceptual models and discovering new laws of polymer crystallization. In addition, the proposed theoretical work complements many experimental efforts being actively pursued worldwide.The results of the proposed research will have impact in numerous applied areas such as polymer processing, and fabrication of polymeric nanomaterials. Most of the materials today are made by processing semicrystalline polymers. These materials constitute a multi-billion-dollar industry. A fundamental understanding of the behavior of this important class of polymeric materials will help to design and process novel polymeric materials with enhanced benefits to our society. Training of graduate students in this challenging research area is strong educational component of this proposal.