Ion-Beam and Surface-Analytical Studies of Macromolecular Surfaces

高分子材料表面和界面的研究对于确定与粘附、涂层、生物相容性、降解和反应性等技术应用相关的结构-性能关系至关重要。在这个提议中，描述了基于初级低能稀有气体离子束引起的溅射和散射的有机和聚合物表面的表面敏感测量。具体来说，Langmuir-Blodgett （LB）薄膜制备技术将用于控制薄膜的结构、取向和聚合程度。这些将被用于研究离子形成过程，从而产生有关链长和聚合链键合的信息。二次离子质谱（SIMS）方法将使用LB膜作为聚合物表面的模型系统，SIMS也将探测膜本身的界面化学。结合平均取向的分子力学计算结果，并与低损伤条件下的实验结果进行比较，研究了有序聚合物表面取向的低能离子散射（ISS）分析。嵌段共聚物、相容性共混物和表面改性聚合物的表面组成研究将通过结合电子显微镜、接触角分析、化学分析电子能谱（角相关方法）、ISS和傅立叶变换红外光谱，以获得一个完整的描述表面和动力学的聚合物界面。

The study of the surfaces and interfaces of polymeric materials is extremely important in determining structure-property relationships relevent to technological applications in adhesion, coatings, biocompatibility, degradation, and reactivity. In this proposal, surface-sensitive measurements of organic and polymeric surfaces are described, based on sputtering induced by and scattering of a primary low-energy noble-gas ion beam. Specifically, Langmuir-Blodgett (LB) thin-film preparation techniques will be used to control structure, orientation, and degree of polymerization of films. These will be utilized to study the ion-formation processes which give rise to information about the chain length and bonding of a polymeric chain. Secondary Ion Mass Spectrometry (SIMS) methods will be developed using the LB film as a model system for the polymer surface, also SIMS will probe the interfacial chemistry of the films themselves. Low-energy Ion Scattering (ISS) analysis of the orientation of ordered polymer surfaces will be studied by combining results from molecular mechanics calculations of average orientation and compared to experimental results under low-damage conditions. Studies of the surface composition of block copolymers, compatible blends, and surface-modified polymers will be accomplished by combining electron microscopy, contact angle analysis, Electron Spectroscopy for Chemical Analysis (angular dependent methods), ISS and Fourier Transform Infrared Spectroscopy to get a complete description of the surface and dynamics of the polymer interface.