Robust, Rapid Cure Structural Film Adhesive for On-Aircraft Repair

On-aircraft repair of systems with sensitive equipment require adhesives that possess mild curing conditions/temperatures and that rapidly achieve a lap shear strength of 2500 psi or greater as these materials will have to bear considerable loads. It is necessary to develop an adhesive that cures at less than 300°F yet maintains high structural strength up to 350°F under hot, wet conditions. Luna Innovations has developed a reactive hot melt adhesive based on polyurethanes which are applied at temperatures below 100°C ( 400°F) Using thiol functional endgroups, Luna will improve upon the moisture cured polyurethane to provide a robust, rapidly curing RHM adhesive. The novel polyurethane adhesive system will be comprised entirely of commercially available monomers, and will possess similar storage, handling and processing properties of traditional film adhesives. BENEFIT: The proposed reactive hot melt adhesive based on thiol-ene functional polyurethanes will be a profound example of combining industrially relevant know-how with the cutting edge of synthetic organic chemistry to produce novel materials with exciting new properties and applications. In academia, thiol-ene and other click chemistries have been ever becoming more popular approaches to achieve complex molecular architectures through efficient reactions. Researchers at Luna Innovations Incorporated make it a high priority to transfer these breakthroughs into useful, commercial applications both to solve the needs of the Air Force and to provide better living through chemistry.