Synthesis of a novel self-assembling NLO polymeric film

By covalently binding chromophore NPP, N-(4-nitrophenyl)-(L)-prolinol, to a structurally controlled cage-like cross-linking polymer (SCCP), a modified nonlinear optical (NLO) polymeric film prepared by "in situ poling and sol -gel" process successfully overcame the fundamental problem of NPP chromoph ores subliming out from the cages of the "doped'' NLO polymeric film when h eated or placed under UV light. Its d(33) (coefficient of second harmonic g eneration) is 2.0 X 10(-8) esu. measured by IR dichroism. The modified film has a low decay of the SHG signal and preserves 94% of the initial value a fter 50 days at room temperature These properties match that of the "doped" film, indicating that the modified film also retains the main advantages o f the "doped" film.