GOALI: Defining Dynamic Morphology, Order-Disorder Transitions, and Interfaces in Gradient Copolymers

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TECHNICAL SUMMARY Advances in materials science occur when synthesis and detailed characterization methods combine to generate new understanding. In this GOALI project, the collaborators will use anionic polymerization to create gradient copolymers with systematic variations in the interfacial dimensions and co-monomer contents. A fundamental premise of the work is that the interfacial transition zones are active components of the overall morphological character of gradient copolymers and play a very important role in final physical properties. The collaborative research team plans to demonstrate that systematic tailoring of the interface in gradient copolymers, with the same overall chemical composition, can lead to a range of final polymer properties. New solid-state NMR experimental strategies, developed in the PI's laboratory, will be an integral part of the project since these methods offer the potential to detect changes in rigid and mobile fractions at the chain level, and identify if one or both co-monomers can occupy different distinct morphological regions. The proposed strategy offers the key benefit of providing component-specific data for each co-monomer component in heterogeneous gradient copolymers across wide temperature ranges. Deliberate mixed-morphology materials will be created and analyzed to discern if physical property improvements (e.g., in impact strength and/or flex modulus) are possible through tailored construction of the amorphous interfacial regions.NON-TECHNICAL SUMMARYProfessor Jeffery White and his research group, in collaboration with Chevron Phillips Chemical Company, seek to discover how to control the creation of useful new materials made from existing macromolecules, but in new ways. These new types of materials are called gradient copolymers, which are created from different types of large molecules that are chemically bonded in different sequences. The collaborators have found through preliminary experiments that relatively small regions out of the total material synthesized, known as the interface (since it corresponds to the transitions in the different types of molecules bonded together), actually have a large impact on the overall bulk behavior of the material. In an effort to find out the contribution of each type of molecule in the mixture that gives rise to desirable or undesirable end properties, advanced characterization experiments have been and will continue to be developed. The unique feature of these types of experiments is that they have the potential to specify which types of molecular structures in the overall material have the largest impact on desirable bulk behavior. Due to the special aspects of this collaboration between university and industrial scientists within the State of Oklahoma, students from all levels will have the opportunity to participate in research, and observe differences in the practice of science and technology in academic and industrial environments. Further, these intelligent schemes for making new materials appear suitable for eliminating the necessary addition of environmentally deleterious additives that have caused problems in earlier materials.