Dynamics and Phase Equilibra of Polymers: Finite Size Effects

本研究的总体目标是发展对约束、表面和界面对聚合物薄膜混合物的动力学和相稳定性影响的微观理解。该策略是使用有关界面的信息作为探针来了解相稳定性和动力学。该策略的一个关键方面是专注于独立“调整”底物和聚合物的分子参数，以控制分子相互作用。这将涉及合成具有不同功能的新型去甲硼烯类聚合物，合成可定制反应性的新型无机二氧化碲基玻璃，以及硅衬底的表面处理。本研究分为两部分，第一部分采用变角椭圆偏振光谱（VASE）和前向反冲光谱（FRES）相结合的方法，研究变厚度均聚物双层间界面厚度的变化；L.从这方面的研究中获得的平衡界面厚度信息将有助于深入了解共聚物（随机和双嵌段）对混合物相稳定性的影响。该提案的第二阶段涉及对这些聚合物与不同特征的基质接触的混合物中润湿层的形成和共存相的相关研究，以便深入了解“界面”场在均聚物混合物中润湿层的形成和生长中的作用。这项工作的另一个方面是利用有关润湿层的信息来开发共聚物对薄膜混合物相稳定性影响的新见解。由于薄膜聚合物在许多技术中起着“主动”和“被动”的作用，因此技术需求激发了人们对这一领域的兴趣。例如，它们在微传感器、大面积发光显示器和选择性薄膜应用中发挥“主动”作用。“被动”应用包括用作磁性存储介质的保护涂层和润滑剂，生物相容性和用作薄膜粘合剂。由于总体性质的信息提供的指导是有限的，因此在这些条件下对聚合物性质有一个基本的了解是至关重要的。* * *

Green 9705101 The overall goal of this study is the development of a microscopic understanding of the effects of confinement and of surfaces and interfaces on the dynamics and phase stability of polymeric thin film mixtures. The strategy is to use information about the interface as a probe to understand the phase stability and dynamics. A critical aspect of this strategy is focused at independently "tuning" the molecular parameters of the substrate and of the polymers in mrder to have control over the molecular interactions. This will involve novel synthesis of new norborene-like polymers with varying functionalities, synthesis of novel inorganic tellurium dioxide-based glasses whose reactivity can be tailored and surface treatments of a silicon substrate. The proposed study is divided into two parts, the first of which involves using a combination of variable angle spectroscopic ellipsometry (VASE) and forward recoil spectrometry (FRES) to study the development of the interfacial thickness between homopolymer bilayers of varying thickness, L. Information learned from the equilibrium interfacial thickness from this aspect of the study will give insight into the effect of copolymers (random and diblock) on the phase stability of the mixtures. The second phase of this proposal involves a related study of the formation of wetting layers and coexistence phases in mixtures of these polymers in contact with the substrates of varying characteristics in order to gain insight into the role of the "interfacial" fields on the formation and growth of the wetting layer in homopolymer mixtures. An additional aspect of this work is to use information about the wetting layer to develop new insights into the effect of copolymers on the phase stability of the thin film mixtures. %%% Interest in this area is motivated by technological need since thin film polymers serve "active" and "passive" roles in many technologies. For example, they serve "active" roles in microsen sors, large area light emitting displays and selective membrane applications. "Passive" applications include use as protective coatings and lubricants for magnetic storage media, biocompatibility and use as thin film adhesives. Because information about bulk properties provides limited guidance, it is critical to develop a fundamental understanding of polymeric properties under these conditions. ***