Synthesis and characterization of thermally crosslinked polyimide with second-order nonlinear optical chromophore

Synthesis of three novel crosslinked polyimides with push-pull azobenzene group has been developed. 4-Nitre4′-[N, N-bis (2-aminoethyl)]aminoazobenzene was first prepared, then poly(amic acid) prepolymer, one crosslinkable component, was obtained by aminolysis of alternating styrene-maleic anhydride copolymer, alternating thiophene-maleic anhydride copolymer or alternating benzofuran-maleic anhydride copolymer with it, and at last the crosslinked second-order nonlinear optical polyimide was synthesized by crosslinking and imidizing poly (amic acid) prepolymer with corresponding alternating copolymer. The crosslinking and imidizing processes were studied by IR and UV-Vis spectra. The chromophore density in one of the crosslinkable components, poly(amic acid) prepolymer, and the thermal stability of crosslinked polyimide thin film were measured by UV-Vis spectra.

Synthesis of three novel crosslinked polyimides with push pull azobenzene group has been developed. 4 Nitro 4′ [N,N bis(2 aminoethyl)]aminoazobenzene was first prepared, then poly(amic acid) prepolymer, one crosslinkable component, was obtained by aminolysis of alternating styrene maleic anhydride copolymer, alternating thiophene maleic anhydride copolymer or alternating benzofuran maleic anhydride copolymer with it, and at last the crosslinked second order nonlinear optical polyimide was synthesized by crosslinking and imidizing poly(amic acid) prepolymer with corresponding alternating copolymer. The crosslinking and imidizing processes were studied by IR and UV Vis spectra. The chromophore density in one of the crosslinkable components, poly(amic acid) prepolymer, and the thermal stability of crosslinked polyimide thin film were measured by UV Vis spectra.