CAREER: Orientational Dynamics in Flows of Thermotropic Polymers

摘要CTS-0093880P。这项建议提出了新的实验方法，结合精心制备的模型聚合物，其目的是明确回答热致聚合物流动的取向稳定性的突出问题。将设计和组装第三代可控环境微观测仪，以直接测量模型材料系列的第一法向应力差和局部和全局取向的各种测量(双折射、紫外二色性、红外二色性和广角X射线散射)。通过研究TLCP链柔性对线性Leslie-Ericksen翻滚参数的影响，以及剪切瞬变过程中微观(取向缺陷)和宏观(双折射)取向的演变，我们将显著提高对TLCP动力学的理解，使之能够与目前的多域模型和进一步的分子模拟发展进行定量比较。我们提出了一项教育计划，将与康涅狄格州当地教师的联系与开发一门新的本科化学工程选修课--《我们的复杂流体的世界》相结合。特别是，计划中的外展工作将包括为高中教师制定一个试点暑期实习计划。聚合物链接，高中教师与化学工程教师合作，开展实践科学项目(4-6周)，专门设计用于在高中课堂上使用的聚合物和其他复杂流体的实验室实验。补充本科课程将首先向学生介绍广泛的与工业相关的复杂流体，包括食品、药品和塑料，以及生物流体，包括滑液和软骨。然后，这门选修课将让学生接触到物质的基本物理性质、微观结构和定量描述，范围从聚合物液体到胶体悬浮液，从表面活性剂溶液到玻璃。

AbstractCTS-0093880P. Mather, University of ConnecticutThis proposal presents new experimental approaches, combined with carefully prepared model polymers, whose aim is to definitively answer outstanding questions of orientational stability for flows of thermotropic polymers. A third-generation controlled environment microheometer will be designed and assembled to allow direct measurements of both first normal stress differences and various measures of local and global orientation (birefringence, UV dichroism, IR dichroism, and wide-angle x-ray scattering) for the series of model materials is proposed. By examining the influence of TLCP chain flexibility on the linear Leslie-Ericksen tumbling parameter, and the evolution of microscopic (orientational defects) and macroscopic (birefringence) orientations in shear transients, we will significantly improve the understanding of TLCP dynamics, enabling both quantitative comparison with present polydomain models and further molecular modeling developments.An education plan is proposed to combine outreach to local teachers in Connecticut with the development of a new undergraduate chemical engineering elective, "Our World of Complex Fluids." In particular, the planned outreach efforts will feature the development of a pilot summer internship program for high school teachers. Polymer Links, in which high school teachers are teamed with chemical engineering faculty to conduct hands-on science projects (4-6 weeks) designed specifically to develop laboratory experiments in polymers and other complex fluids for use in the high school classroom. The complementary undergraduate course will first introduce students to a wide range of industrially relevant complex fluids, including foodstuffs, pharmaceuticals, and plastics along with biological fluids, including synovial fluid and cartilage. Then, this elective will expose students to underlying physical properties, microstructures, and quantitative descriptions of substances ranging from polymeric fluids to colloidal suspensions and from surfactant solutions to glasses.