SBIR Phase II: Surface Engineering of Metals with Plasma Polymers

这个小型企业创新研究(SBIR)第二阶段项目将用一种对环境无害的工艺取代目前对环境有害的金属前处理工艺，即在金属表面进行蚀刻，然后在金属表面涂覆一层亚微米的等离子体聚合二氧化硅薄膜。目前用于涂装和粘接的金属前处理工艺表现良好，但会产生大量的废物，包括六价铬和各种无机酸。为了获得比目前最先进的湿化学表面处理更好的性能，等离子体聚合薄膜的表面化学和形态需要针对与粘合剂的特定相互作用进行量身定制。包括基片化学、单体化学和离子动能在内的变量对等离子体聚合物的表面化学和形态的影响将被确定。通过将原位分析技术与胶粘剂试件的加速老化和力学测试相结合，将开发出一种基于等离子体聚合的优越的、环境友好的工艺并将其商业化。通过控制等离子体聚合物表面的沉积条件和/或化学衍生，这些底漆将具有为粘接化学量身定做的易于理解的形貌和表面成分。

This Small Business Innovation Research (SBIR) Phase II project will replace current environmentally damaging metal pretreatment processes with an environmentally benign process whereby the metal surface is etched then coated with a sub-micron film of plasma polymerized SiO2. Current metal pretreatment processes for painting and adhesive bonding perform well, but generate tremendous volumes of wastes, including hexavalent chromium and various inorganic acids. To obtain performance superior to the current state-of-the-art wet chemical surface treatments, the surface chemistry and morphology of the plasma polymerized films need to be tailored for specific interactions with the adhesive. Effects of variables including substrate chemistry, monomer chemistry, and ion kinetic energy on surface chemistry and morphology of plasma polymers will be determined. Then, the effect of the resulting structure on the strength and durability of adhesive joints will be determined.By combining in-situ analytical techniques with accelerated aging and mechanical testing of adhesive specimens, a superior, environmentally benign process based on plasma polymerization will be developed and commercialized. These primers will have well understood morphologies and surface compositions tailored to the adhesive chemistry through control of the deposition conditions and/or chemical derivitization of the plasma polymer surface.