Acquisition of a Rheometer and Materials Processing Equipment

9305286温尼流变法是测量材料粘弹性特性最常用和最可靠的技术。这种流变仪，流变固体分析仪，满足校园许多研究人员的样品配置要求，因为它可以容纳熔融聚合物，玻璃薄膜，纤维，浓缩溶液，橡胶和复合材料。加工设备包括用于组合各种组件的熔体混合器和用于形成样品以供随后的结构和机械评估的小型挤出机。在整个工程与应用科学学院和艺术与科学学院，这种新设备将补充宾夕法尼亚大学教师目前使用的实验技术。在我们的研究实验室中，我们通过使用挥发性溶剂制备共聚物/均聚物共混物，这是工业上避免的做法，并使用透射电子显微镜和小角度x射线散射来评估形貌和相行为。有了提议的设备，混合物将在不使用溶剂的情况下制备，我们广泛的形态学研究将与新的流变学研究相关。在另一个例子中，宾夕法尼亚大学目前正在使用合成技术元素和热分析以及广角x射线散射来研究预陶瓷聚合物。新设备将提供一种使用挤出机制造纤维的方法，并使用流变仪研究预陶瓷聚合物的机械性能。其他研究项目包括：将导电聚合物的结晶度和电导率与材料的粘弹性特性联系起来，通过扩散和零剪切粘度来比较聚合物混合物中的分子运动，并通过中子散射和流变学测试离聚体溶液的理论模型。该项目的一个重要目标是通过使用类似的加工技术，并更加强调微观结构和宏观特性的相互依赖性，使宾夕法尼亚大学的研究与工业问题更加相关。* * *

9305286 Winey Rheometry is the most common and reliable technique for measuring viscoelastic properties of materials. This rheometer, a Rheometrics Solids Analyzer, satisfies the sample configuration requirements of many researchers on campus, in that it can accommodate molten polymers, glassy thin films, fibers, concentrated solutions, rubber, and composites. The processing equipment, includes a melt mixer for combining a variety of components and a small extruder to form samples for subsequent structural and mechanical evaluation. Throughout the School of Engineering and Applied Science and the School of Arts and Sciences, this new equipment will compliment the experimental techniques currently used by Penn faculty. In our research laboratories we prepare copolymer/homopolymer blends by using a volatile solvent, a practice which is avoided by industry, and evaluate the morphology and phase behavior using transmission electron microscopy and small angle x-ray scattering. With the proposed equipment, blends will be prepared without using a solvent and our extensive morphological studies will be related to new rheological studies. In another example, preceramic polymers are currently studied at Penn by using synthetic techniques elemental and thermal analysis, and wide angle x-ray scattering. The new equipment will provide a means of fabricating fibers, using the extruder, and studying the mechanical properties of the preceramic polymers, using the rheometer. Other research projects include: relating the percent crystallinity and conductivity of a conducting polymer with the viscoelastic properties of the materials, comparing the molecular motion in polymer blends as measured by both diffusion and zero shear viscosity, and testing theoretical models of ionomer solutions by neutron scattering and rheology. An important goal of this project is to make the research at Penn more relevant to industrial concerns by using similar processing techniques and g iving more emphasis to the interdependence of microscopic structure and macroscopic properties. ***