Crystallization and Structure Formation in Model Polymer Blends

9900638 runt控制聚合物共混物的固态微观结构和结晶的关键因素比纯半结晶体系的关键因素了解得更少，部分原因是由于这种混合物固有的复杂性。PI最近的工作（主要使用小角度x射线散射测量）对包含弱相互作用和强相互作用的非晶态聚合物的模型熔融混溶共混物进行了研究，从而深入了解了影响这些体系最终微观结构的因素。这项初步工作，连同其他初步实验，为进一步研究指明了一些重要的方向。拟议的研究主要分为两个方面。主要重点是发展对模型共混物中聚环氧乙烷（PEO）结晶和微观结构发展的基本理解。这方面的工作将主要通过同时进行小角和广角x射线散射实验来进行。此外，PI将对PEO在共混物中的球晶生长动力学进行平行研究，特别强调强分子间相互作用的影响。第二个重点领域涉及单晶和熔融结晶PEO和共混物的固态结构及其介电弛豫行为之间的关系。从这项工作中得出的原理应该是完全通用的，并为多组分聚合物体系的性能优化提供了基础。

9900638RuntThe key factors controlling the soid-state microstructure and crystallization of polymer blends are less well understood than those of neat semi-crystalline systems, due in part to the inherent complexity of such mixtures. Recent work by the PI (using principally small angle x-ray scattering measurements) on model melt-miscible blends containing weakly-and strongly-interacting amorphous polymers has provided insight into the factors that influence the final microstructure in these systems. This initial work, along with other preliminary experiments, point to a number of important directions for further research.The proposed research falls into two main areas. The primary focus is on developing a fundamental understanding of crystallization and microstructure development of poly(ethylene oxide) [PEO" in model blends. This aspect of the work will be conducted primarily using simultaneous small-and wide-angle x-ray scattering experiments. In addition, the PI will undertake a parallel study of the kinetics of spherulitic growth of PEO in blends, with particular emphasis on the influence of strong intermolecular interactions. The second focus area concerns the relationship between the solid-state structure of single crystalline and melt-crystallized PEO and blends, and their dielectric relaxation behavior. The principles derived from this work should be completlely general and provide a basis for optimal tailoring of properties in multicomponent polymer systems.