CAREER: X-ray Absorption Spectroscopy of Thermal Behavior in Polymers

小行星9733068 这个EPSCoR共同资助的CAREER奖将主要使用X射线吸收光谱（XAS）来检查玻璃化转变时的动力学和结构响应。 玻璃化转变是高分子材料中最重要的现象之一。 随着玻璃化转变发生的基本微观结构变化还没有得到很好的理解，也许更重要的是，Tg在特定温度下发生的根本原因还没有被理解。 其他技术，包括核磁共振光谱和中子散射，表明局部结构和动态变化发生在玻璃化转变。 XAS将用于获得定量和精确的结构信息。 初步数据表明，XAS可用于检查在玻璃化转变的局部变化。 该提案描述了一个广泛的实验，将检查发生在当地一级的聚合物的玻璃化转变过程中的重要变化。 这些实验将使一个林德曼型的玻璃化转变的方法，其他人建议的方法，并在本提案中探讨的评价。 该项目的教育部分将涉及少数民族工程计划（MEP）。 俄克拉荷马州大学的近500名本科生是欧洲议会议员，该议员仅限于历史上代表性不足的黑人、西班牙裔和美洲印第安人少数民族。 教师和学生之间的一对一互动是招聘和留住这些学生的关键之一。 PI与MEP计划的联系包括本科生经历的各个方面，从招聘过程到毕业。 它将包括前往主要是少数民族高中和会谈，旨在帮助招聘过程。 ***

9733068 Grady This EPSCoR co-funded CAREER award will use primarily X-ray absorption spectroscopy (XAS) to examine responses in dynamics and structure at the glass transition. The glass transition is one of the most important phenomena in polymeric materials. The fundamental microscopic structural changes that occur with the glass transition are not well understood, and perhaps even more importantly, the fundamental reason that Tg occurs at the specific temperature it does for each polymer is not understood. Other techniques, including NMR spectroscopy and neutron scattering, show that local structural and dynamic changes occur at the glass transition. XAS will be used to obtain quantitative and precise structural information. Preliminary data show that XAS can be used to examine local changes at the glass transition. This proposal describes a broad range of experimentation which will examine the important changes occurring at the local level as a polymer progresses through its glass transition. These experiments will enable an evaluation of a Lindemann-type approach to the glass transition, an approach suggested by others and explored in this proposal. %%% The educational component of this project will involve the Minority Engineering Program (MEP). Almost 500 undergraduates at the University of Oklahoma are members of the MEP, which is limited to the historically underrepresented Black, Hispanic and American Indian ethnic minorities. One-on-one interactions between faculty and students are one of the keys to recruiting and retaining these students. The PI's association with the MEP program includes all facets of the undergraduate experience, from the recruiting process to graduation. It will involve travel to primarily minority high schools and talks designed to help with the recruiting process. ***