Specific Interactions in Polymer Systems

这两个合作伙伴将继续研究特定相互作用对聚合物共混物相行为的影响。 拟议的工作的一部分涉及完成几年前开始的工作链结构的影响，在解决方案和共混物中，其中的组件包含相互氢键的官能团的数量一样和不一样的接触。 这些系统特别适合研究，因为红外光谱可以用来计算精心选择的系统中的接触次数。 正在进行的工作涉及超支化和树枝状聚合物中的支化效应，交联网络中的网眼尺寸和嵌段共聚物共混物中的微相分离。 拟议的研究的第二部分涉及一种新技术，二维傅里叶变换红外/介电光谱仪的应用。 介电弛豫测量已被用于多年的聚合物链的动力学的探针，通过检测的过渡和弛豫，是各种类型的耦合或局部运动的结果。 红外光谱提供了分子水平结构的探针，在某些系统中，分子间相互作用。 显然，一种技术（或者更准确地说，一种混合技术）可以测量各种跃迁和弛豫的温度和频率范围，同时探测所涉及的官能团及其运动耦合的程度，这将是一种非常强大的分析工具。 预计该仪器将开辟各种新的研究领域，本科生将参与“侦察”实验，作为他们高级项目的一部分，以帮助探索和建立这些领域。 同时，这种混合光谱仪将用于探索与我们的研究的主要推力相关的问题，这些问题以前无法解决，特别是缔合体系中官能团和聚合物链的动力学。这一新的研究领域在加强研究活动和教育方面具有相当大的潜力。 就前者而言，该技术的发展应该允许探索各种材料中涉及弛豫和转变的官能团，而不仅仅是聚合物。 在教育方面，通过让本科生参与研究、技术开发研讨会和将该仪器纳入我们的本科生实验室的机制，将教授和强调将调查方法和技术相结合以解决复杂问题的重要性。

The two co-PI's will continue research on the effect of specify interactions on the phase behavior of polymer blends. One part of the proposed work concerns the completion of work initiated a few years ago on the effect of chain architecture on the number of like and un-like contacts in solutions and blends where the components contain functional groups that hydrogen bond to one another. These systems are particularly amenable to study because infrared spectroscopy can be used to count the number of contacts in well-chosen systems. Work in progress involves the effect of branching in hyperbranched and dendrimer-like polymers, mesh size in cross-linked networks and microphase separation in blends involving block copolymers. The second part of the proposed research involves the application of a new technique, a two-dimensional Fourier transform infrared/dielectric spectrometer. Dielectric relaxation measurements have been used for many years as a probe of the dynamics of polymer chains, through the detection of the transitions and relaxations that are a result of various types of coupled or local motions. Infrared spectroscopy provides a probe of molecular level structure and, in certain systems, intermolecular interactions. Clearly, a technique (or, more accurately, a hybrid-technique) that can measure the temperature and frequency range of various transitions and relaxation's, while simultaneously probing the functional groups involved and the degree to which their motions are coupled, would be an extremely powerful analytical tool. It is expected that this instrument will open up various new areas of research and undergraduate students will be involved in "scouting" experiments as part of their senior projects to help explore and establish these. At the same time, this hybrid spectrometer will be used to explore problems associated with the major thrust of our research that could not be tackled previously, particularly the dynamics of functional groups and polymer chains in associating systems.%%%This new area of research has considerable potential for enhancing both research activities and education. In terms of the former, the development of the technique should allow the functional groups involved in relaxations and transitions in various materials, not just polymers, to be explored. In terms of education, through the mechanisms of involving undergraduates in the research, seminars on technique development and incorporating this instrument into our undergraduate laboratories, the importance of combining methods of investigation and techniques in order to tackle complex problems will be taught and emphasized.