SBIR-STTR Award

The proposal describes the improvements that can be made using expanding monomers in coating compositions for aircraft transparencies such as those used in polycarbonate windows. It shows how the bonding between the coating film and the substrate can be made extremely intimate so that changes in temperature, pressure and humidity do not result in delamination or destruction of coating properties. A program is outlines which will relate the physical properties of the cured polymeric film with that of the substrate. To accomplish this task in an effective manner, the proposal cites the unique experience of this company, Epolin, inc. And its founder, Dr. Murray Cohen as pioneers in the development of expanding polymer technology.

Phase I established the feasibility for the development of superior optical coatings on plastic panels, notably polycarbonate. The success of this effort was based upon the use of monomeric materials in cured coating compositions which reduce significantly the amount of shrinkage that normally occurs when state"of-the-art compositions are cured. Data from phase I are given which conclude that the most promising coatings were based on a dual cure cationic epoxy system which is initiated first by ultraviolet light and completed by thermal post-bake. We can make use of a preformed spiroorthocarbonate, nsoc, or an inzsitu formed spiroorthoester as the expanding monomer. Phase II will complete the development of these coatings. The best -properties of state-of-the-art compositions will be retained. At the same time improvements in adhesion, impact resistance and lowered moisture uptake can be gained. Evaluations are proposed which will give quantitative evidence needed for commercial development. American optical co. Has agreed to perform quasi-field testing to help show what final modifications must be made to the coating comoposition.