A smart optical material characterized in that when the material is at ambient temperature (≤30° C.), it is opaque to at least one color light in the visible light spectrum and when the material is at an elevated temperature of at least 80° C., it is substantially transparent to the at least one color light. The smart optical material is also characterized as having before thermal aging an elongation-at-break of at least 15% and after thermal aging in air at 200° C. for seven days an elongation-at-break that is unchanged or is at least 12% and has decreased by from >0% to less than 50%. Also included are related formulations, methods, uses, articles and devices.