Chromophore-functionalised polymides with high-poling stabilities of the nonlinear optical effect at elevated temperature

Functionalised second-order nonlinear optical (NLO) polyimides have been developed. The key challenge in our approach was a one-step synthesis of these polymers, by reaction of di(hydroxyalkyl) chromophores and diimides utilising the Mitsunobu reaction. Glass transition temperatures in the range of 205–224°C were obtained. Thin spincoated films of the polymers were corona-poled and analysed by second-harmonic generation; values for d33 of 30 pm/V were obtained. Poled order stability measurements over periods of 210–500 h resulted in 70–90% of remaining NLO-response at 125°C.