Water-Borne Self-Assembled Monolayers and Films

该提案旨在开发形成自组装单分子膜(SAMS)的新方法，从而扩大这些分子膜的用途和应用。该方法利用烷基硫酸盐自组装膜从水溶液中组装到金属载体上，而不是传统的有机溶剂。这项拟议的工作利用了水溶性吸附物的分子设计和对水处理变量的控制，包括pH、电化学良性的水溶剂。通过界面电容测量等电化学技术，可以对自组装膜的信息进行现场监测。拟议的工作还将调查在应用中使用水性自组装膜的可行性。通过疏水效应，由水溶液形成的低能表面将用作形成表面活性剂薄膜或层状自组装系统的模板，这些系统可以从衬底上移除并用作膜分离的超薄皮肤。这项拟议的研究还为应用自组装膜来缓解腐蚀等工程问题提供了新的机会。水基自组装膜将被用作水相缓蚀剂，以提供和保持超薄的阻挡层，阻止水物种与水相连续接触的底层金属如铜或铁的传输。在水溶液中形成自组装单分子膜的优点包括(1)对薄膜和涂层进行环境清洁的处理，(2)能够利用疏水相互作用设计新型的自组装体系，(3)使用添加的表面活性剂、电化学势和pH来获得对自组装膜的分子水平的前所未有的控制，以及(4)在水体系中开发自组装膜的新技术应用。水溶液中SAM形成的研究可能会引发胶体和表面化学两个不同领域的知识融合，涉及胶束体系和自组装单分子膜的研究。这种融合将导致具有独特性质、优异稳定性和诱人的应用潜力的新型自组装系统的生成大幅增加。

ABSTRACTCTS-9983966Jennings - Vanderbilt U.This proposal seeks to develop new methodologies for forming self-assembled monolayers (SAMS) that will expand the uses and applications of these molecular films. The approach utilizes the assembly of alkanethiolate SAMs onto metal supports from aqueous solutions instead of the traditional organic solvents. The proposed work exploits the molecular design of water-soluble adsorbates and the control of aqueous processing variables including pH, electrochemically benign aqueous solvents. The information of the SAMs can be monitored in situ by electrochemical techniques such as interfacial capacitance measurements. The proposed work will also investigate the feasibility of using water-borne SAMs in applications. Through the hydrophobic effect, the low-energy surfaces formed from aqueous solvents will serve templates for the formation of surfactant films or layered, self assembling systems that can be removed from the substrate and used as ultrathin skins for membrane separations. The proposed research also provides new opportunities for applying SAMs to alleviate engineering problems such as corrosion. Water-borne SAMs will be used as aqueous-phase corrosion inhibitors to provide and maintain a ultrathin barrier layer that impedes the transport of aqueous species to an underlying metal such as copper or iron in continuous contact with an aqueous phase.The advantages of forming self-assembled monolayers in aqueous solutions include (1) environmentally clean processing of films and coating, (2) the ability to utilize hydrophobic interactions to engineer novel self-assembled systems (3) the use of added surfactant, electrochemical potential, and pH to gain an unprecedented control over the molecular-level properties of SAMs, and (4) the development of new technological applications for SAMs in aqueous systems. The study of SAM formation in aqueous solution will likely spark the fusion of knowledge from two separate areas of colloid and surface chemistry involving research on micellar systems and that on self-assembled monolayers. This fusion should result in a dramatic increase in the generation of novel self-assembled systems with unique properties, superior stabilities, and attractive potential for applications.