Effect of Processing Variables on the Structure and Properties of Plasma Polymerized Films on Metal Substrates

项目概要建议书编号：CTS-9407809 P.I.：博埃里奥研究所：辛辛那提大学等离子体聚合是一种过程，在这个过程中，当向气体施加电场时，自由电子与单体分子之间的碰撞，在“单体”的低压气体或等离子体中形成离子和自由基等活性物种。活性物种与自身或与单体反应，在暴露在等离子体中的固体表面形成聚合物涂层。等离子体聚合是一种非常有吸引力的金属研究前处理方法，因为它可以将材料的合成和加工结合到一个步骤中。许多关于等离子体聚合的研究已被报道，但大多数只集中在一个方面，例如工艺变量对成膜速度的影响。在这项研究中，辛辛那提大学与福特汽车公司和固特异轮胎橡胶公司合作，确定用于在金属衬底上沉积等离子体聚合薄膜的工艺变量、薄膜的分子结构，特别是表面和界面结构，以及作为橡胶-金属和光谱分析(XPS)、二次离子质谱仪(SIMS)、俄歇电子光谱(AES)、反射吸收红外光谱(RAIR)、椭偏仪、表面增强拉曼散射(SERS)、扫描电子显微镜(SEM)、原子力显微镜(AFM)将用来确定工艺参数，如放电功率和频率、单体、流量、压力和衬底表面化学成分对薄膜分子结构和形貌的影响。将使用电化学阻抗谱(EIS)、断裂力学测试和工业测试方法来确定薄膜的性能特征，例如它们对金属衬底的腐蚀保护、沉积在金属衬底上的薄膜的界面断裂能，以及作为橡胶与金属和结构胶粘剂粘接底漆的薄膜的性能。在断裂力学和粘接试验后，将使用表面分析来检查试件的破坏表面，以确定破坏机制。所获得的结果将用于建立用于沉积薄膜的工艺变量、它们的分子结构和它们的性能之间的关系，并将代表着对重要的、快速扩展的聚合物薄膜领域的知识库的显著增强。与福特的合作将主要涉及铝材的结构粘接和表面分析。与固特异的合作将涉及橡胶与金属的粘合和表面分析。

Project Summary Proposal Number: CTS-9407809 P.I.: Boerio Institution: University of Cincinnati Plasma polymerization is a process in which active species such as ions and radicals are formed in a low pressure gas or plasma of a "monomer" by collisions between free electrons and monomer molecules when an electric field is applied to the gas. The active species react with themselves or with monomers to form polymer coatings on the surfaces of solids that are exposed to the plasma. Plasma polymerization is an extremely attractive process for pretreatment of investigations of metals since it enables materials synthesis and processing to be combined into one step. Many investigations of plasma polymerization have been reported but most have focused on only one aspect, such as the effect of processing variables on the rate of film formation. In this research, the University of Cincinnati is collaborating with Ford Motor Co. and Goodyear Tire and Rubber Co. to determine relationships between the processing variables that are used to deposit plasma polymerized films on metal substrates, the molecular structure of the films, especially the surface and interfacial structures, and the performance of the films as primers for rubber-to-metal and spectroscopy (XPS), secondary ion mass spectrometry (SIMS), Auger electron spectroscopy (AES), reflection-absorption infrared spectroscopy (RAIR), ellipsometry, surface-enhanced Raman scattering (SERS), scanning electron microscopy (SEM), and atomic force microscopy (AFM) will be used to determine the effect of processing variables such as discharge power and frequency, monomer, flow rate, pressure, and substrate surface chemistry on the molecular structure and morphology of the films. Electrochemical impedance spectroscopy (EIS), fracture mechanics tests, and industrial test methods will be used to determine performance characteristics of the films such as the corrosion protection they impart to metal substrates, the interfacial fracture energy of films deposited on metal substrates, and the properties of the films as primers for rubber-to-metal and structural adhesive bonding. Surface analysis will be used to examine the failure surfaces of specimens after fracture mechanics and adhesive bonding tests to determine the failure mechanisms. The results obtained will be used to develop relationships between the processing variables used to deposit the films, their molecular structure, and their properties and will represent a significant enhancement to the knowledge base in the important, rapidly expanding field of thin polymer films. Collaboration with Ford will mostly involve structural adhesive bonding of aluminum and surface analysis. Collaboration with Goodyear will involve rubber-to-metal bonding and surface analysis.