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

技术综述材料科学的进步是当合成和详细的表征方法结合起来产生新的理解时发生的。在这个GALI项目中，合作者将使用阴离子聚合来创建界面尺寸和共聚单体含量有系统变化的梯度共聚物。这项工作的一个基本前提是，界面过渡区是梯度共聚物整体形态特征的活跃成分，对最终的物理性能起着非常重要的作用。合作研究团队计划证明，在总体化学成分相同的情况下，对梯度共聚物的界面进行系统的剪裁可以产生一系列最终的聚合物性能。PI实验室开发的新的固态核磁共振实验策略将是该项目不可或缺的一部分，因为这些方法提供了在链水平上检测刚性和可移动部分的变化的可能性，并确定是否一个或两个共单体可以占据不同的不同形态区域。建议的策略提供了在宽温度范围内为非均相梯度共聚聚合物中的每个共聚单体组分提供特定组分数据的关键优势。精心设计的混合形态材料将被创建和分析，以确定是否可以通过量身定做的非晶界面区结构来改善物理性能(例如，在冲击强度和/或弯曲模数方面)。非技术摘要Jeffery White教授和他的研究小组与雪佛龙菲利普斯化工公司合作，试图发现如何以新的方式控制由现有大分子制成的有用新材料的创建。这些新型材料被称为梯度共聚物，它是由不同类型的大分子以不同的顺序化学键合而成。合作者通过初步实验发现，在合成的全部材料中，相对较小的区域被称为界面(因为它对应于结合在一起的不同类型分子的转变)，实际上对材料的整体行为有很大影响。为了找出混合物中每种类型的分子对产生理想或不理想的末端性质的贡献，已经并将继续开展先进的表征实验。这些类型的实验的独特之处在于，它们有可能指定整体材料中哪些类型的分子结构对所需的整体行为具有最大的影响。由于俄克拉荷马州大学和工业科学家之间合作的特殊方面，来自各个层次的学生将有机会参与研究，并观察学术和工业环境中科学和技术实践的差异。此外，这些制造新材料的智能方案似乎适合于消除在早期材料中造成问题的必要的有害环境添加剂的添加。

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.