UV Curable Elastomeric Materials

摘要

Elastomeric coatings used for aerospace applications typically contain volatile organic compounds (VOC) and hazardous air pollutants (HAP) such as methyl ethyl ketone, methyl isobutyl ketone, toluene, or xylene at levels as high as 600 g/L. Despite this fact, these coatings are currently exempt from 1998 National Emissions Standards for Hazardous Air Pollutants (NESHAP) due to the lack of a suitable low-VOC substitute as well as their low usage volume at the time the regulation was drafted and passed. Since that time, the requirement for use in aerospace applications of these coatings has substantially increased. Over the next decade, the U.S. military plans to deploy several new weapons systems that use elastomeric coatings and technology to retrofit several existing systems, including the use of elastomeric coatings to improve the performance of the aircraft. As a result, the emission of VOC from elastomeric coatings is expected to increase to about 2 million pounds per year. In addition to environmental issues, the process for applying elastomeric coatings is time and labor intensive due to the relatively thick coatings that are applied. The required thickness is achieved by applying multiple layers. Applying these coating to an aircraft or missile weapon system is a very cumbersome process and usually requires multiple shifts. The objective of this program is the demonstration and validation of innovative technologies that will result in a nearly 100% reduction of VOC emissions from an elastomeric coating spray application. The coating resin used in this program was developed by Foster-Miller, Inc. (FMI) in part under Strategic Environmental Research and Development (SERDP) funding (WP-1180). This specific resin was chosen based on its potential ability to allow cure of thick layers of filled formulations.