A series of chromophore-functionalized polyimide prepolymers with excellent processibility were prepared by a Michael addition reaction of diamine chromophore 2 with structurally different bismaleimide (BMI) monomers. The effects of the BMI moiety's structure and thermal curing condition on glass transition temperature (Tg) and thermal stability of the polyimides were studied by DSC, TGA, and FTIR. Among the five cured polyimides, PI3, bearing a sulfone moiety, exhibited the highest Tg and thermal decomposition temperature (Td). Its corresponding prepolymer, PP3, was selected to evaluate NLO properties in a simultaneously poling and thermal polymerization process. A relatively large poling-order parameter was observed. The second-order nonlinear coefficient, d33, was 25 pm/V at 1064 nm fundamental wavelength. The second harmonic generation signal was almost without decay up to 170 °C.
|Number of pages||8|
|Journal||Journal of Polymer Science, Part A: Polymer Chemistry|
|State||Published - 15 Sep 1999|