Two-Photon Photocuring for Non-Autoclave Fabrication

Physical Optics Corporation (POC) proposes to develop a new laser-induced Two-Photon Curing (LITPC) system for non-autoclave curing of polymers through illumination by infrared (IR) laser emission. This system will be used by U.S. Air Force personnel forthe fast repair of composite materials in field conditions. In contrast with current curing technologies based on ultraviolet (UV) illumination, the proposed system will permit effective treatment of deep cracks and caverns. The improved depth of curingwill be achieved through the utilization of the IR emission and specially developed chromophores added to the monomer compounds. The selected monomers have low absorption for IR light while chromophores will have significantly enhanced two-photonabsorption in IR region. In Phase I, POC successfully demonstrated the two-photon absorption technology for IR polymer curing, developed means for increasing the rate and volume of polymerization under a laser illumination, and tested chromophores withenhanced two-photon absorption in the IR spectrum. In Phase II, POC will develop a prototype of a LITPC system for IR curing of polymers and will develop the technology for its use with selected compositions of light-curable monomers and effectivetwo-photon absorbing chromophores.