Highly thermally stable electro-optic response in poled guest-host polyimide systems cured at 360°C

In a major development of the new poling process for electro-optic polyimide guest-host systems [Wu et al., Appl. Phys. Lett. 58, 225 (1991)], a thermally stable EO response at 200°C for 80 h is demonstrated for poled polyimide films cured at 250°C for 1 h plus an additional curing at 360°C for 0.5 h. Thermal stability at 300°C for 2 h is demonstrated for the same system cured at 360°C for 0.25 h plus an additional curing at 300°C for 0.33 h. High-temperature densification curing (360°C) is found to be essential in realizing a thermally stable EO response of poled guest-host polyimides at high temperatures.