Materials World Network, SusChEM: Hybrid Sol-Gel Route to Chromate-free Anticorrosive Coatings

技术概述：用六价铬进行表面处理是钝化金属的一种常见的工业实践。然而，铬(VI)是一种已知的致癌物。用新型无铬防腐涂料取代含铬(VI)涂料是一个公共卫生优先事项。本研究研究了掺杂和非掺杂有机-无机混合玻璃的形成，这种玻璃是通过固结“熔融凝胶”而获得的。熔融凝胶具有疏水性、无孔性和气体不渗透性，密封温度较低(135至200摄氏度)，可以直接涂在金属和其他基材上。这项研究的重点是熔融凝胶的结构和化学方面，这些凝胶限制了气体的渗透性，并为金属表面提供了保护。人们感兴趣的一种衬底是镁，因为它密度低、强度高、导热性和导电性好、弹性系数低，因此具有更好的防腐性能的镁合金在汽车、航空航天和生物医学应用中尤其令人感兴趣。在材料研究司的支持下，这个材料世界网络、可持续化学、工程项目建立在美国的Andrei Jitianu(纽约雷曼学院)和Lisa Klein(罗格斯大学)和西班牙的Mario Aparicio(Cerámica y Vidrio研究所、Consejo Superior de Investigacy Científias(CSIC))之间的紧密合作基础上。非技术摘要：传统的金属防腐涂料含有铬(IV)，这是一种已知致癌的有毒物质。为了用更安全的替代品取代这种有害物质，该项目将准备和研究一类含有缓蚀剂的有机-无机“熔融凝胶”。熔融凝胶是通过需要低温处理的简单工艺获得的无孔屏障。它们通过与金属的粘附性和阻止气体和水蒸气通过涂层的传输的能力来防止金属的环境退化。我们的材料世界网络由3个合作伙伴组成，分别是雷曼学院的化学系、罗格斯大学的材料科学与工程系以及西班牙马德里的陶瓷与玻璃研究所(CSIC)。通过结合三个实验室在溶胶-凝胶处理和电化学测试方面的经验，该团队将完成对镁合金和钢的腐蚀保护涂层形成机理的全面研究，这两种涂层通常用于航空航天、汽车和生物兼容的医疗植入物应用。通过这项研究计划，将分享在防腐和密封屏障应用中使用熔融凝胶的更多了解和实用技术。同时，该计划将通过国际多学科方法，在化学、材料科学和腐蚀等相关主题上对学生进行教育。计划进行科学家和学生的交流，以更全面地研究防腐涂料。来自代表不足群体的学生的机会将包括雷曼学院-CUNY的参与，这是一家联邦承认的拉美裔少数族裔服务机构。

TECHNICAL SUMMARY:Surface treatments with Cr(VI) are a common industrial practice for passivating metals. However, Cr(VI) is a known carcinogen. Replacement of Cr (VI)-containing coatings with new chromate-free anticorrosive coatings is a public health priority. This research investigates the formation of doped and undoped hybrid organic-inorganic glasses, which are obtained by consolidating "melting gels". Melting gels are hydrophobic, nonporous and gas impermeable with low sealing temperatures (between 135 and 200 degrees centigrade), and they can be applied directly onto metals and other substrates. The research focuses on the structural and chemical aspects of melting gels that limit gas permeability and impart protection to metal surfaces. One substrate of interest is magnesium, because of its low density, high strength, good thermal and electrical conductivity, and low elastic modulus, making magnesium alloys with improved corrosion protection particularly interesting in auto, aerospace and biomedical applications. With support from the Division of Materials Research, this Materials World Network, Sustainable Chemistry, Engineering project is built on a strong collaboration between the PIs Andrei Jitianu (Lehman College City University of New York) and Lisa Klein (Rutgers University) from US and Mario Aparicio (Instituto de Cerámica y Vidrio, Consejo Superior de Investigaciones Científicas (CSIC)) from Spain. NON-TECHNICAL SUMMARY:Traditional anti-corrosion coatings for metals contain Cr(IV), a toxic material known to cause cancer. In an effort to replace this harmful material with a safer alternative, the project will prepare and study a use class of hybrid organic-inorganic "melting gels" that contain corrosion inhibitors. Melting gels are non-porous barriers obtained by a simple process that requires low temperature processing. They prevent environmental degradation of metals through their adherence to metals and their ability to hinder the transport of gases and water vapor through the coatings. Our Materials World Network consists of 3 partners, the Chemistry Department at Lehman College, the Materials Science & Engineering Department at Rutgers University, and the Institute for Ceramics and Glass (CSIC) in Madrid, Spain. By combining the expertise of three laboratories with experience in sol-gel processing and electrochemical testing, the team will complete a comprehensive study on the mechanisms for forming corrosion protection coatings for magnesium alloys and steels, which are used commonly for aerospace, automotive, and biocompatible medical implant applications. Through this research program, greater understanding and practical know-how in the use of melting gels for anticorrosive and hermetic barrier applications will be shared. At the same time, this program will educate students in relevant topics of chemistry, materials science and corrosion through an international multidisciplinary approach. Exchanges of scientists and students are planned to make a more comprehensive study of anticorrosive coatings. Opportunities for students from underrepresented groups will be included by the participation of Lehman College-CUNY, a federally recognized Hispanic minority serving institution.