UV curable Polysobutylene Oligomers for Photonic Application

A novel radiation curable photo-polymer comprised of a vinyl ether functional polyisobutylene oligomer is described. One-part formulations undergo UV cure in seconds through a cationic mechanism. The UV cured films exhibit mechanical flexibility, high moisture barrier, and good thermal / oxidative stability. Formulations with conventional vinyl ether and epoxy reactive diluents allow for tailoring the refractive index in the 1.48-1.50 range at 589 nm. The UV cured films exhibit high transparency in the 400-700 nm wavelength region and stable refractive index after accelerated aging. An example of an encapsulated device sealed in a glass case passing 1000 hours of accelerated aging at 85°C and 85% relative humidity is presented.