Novel chromophore with tricyanocyclopentenone electronic acceptor and its application in organic EO polymers

Abstract

Novel organic second nonlinear optical chromophore GL-1 based on tricyanocyclopentenone (TCNP) electronic acceptor group were designed and synthesized in this paper. The structure of chromophore GL-1 is characterized by mass spectrum and nuclear magnetic resonance spectroscopy. Chromophore FTC based on traditional tricyanofuran (TCF) electronic acceptor was also prepared as the contrast. Their delocalized energy levels were estimated by UV–Vis spectra. Their thermal properties were studied by thermogravimetric analysis. Obviously, chromophore GL-1 showed lower delocalized energy levels and higher thermal decomposition temperature (just about 286 °C). Electro-optics polymers prepared based on chromophore GL-1 showed the largest SHG coefficients of about 119 pm/V, which was about two times higher than chromophore FTC (about 68 pm/V). These advantages of chromophore GL-1 are attributed to the improvement of first order hyperpolarizability and the attenuatation of intermolecular dipole interaction by the introduction of tricyanocyclopentenone electronic acceptor. And in another word, tricyanocyclopentenone electronic acceptor may be a promising way to drastically change the nonlinear optical features of the titled compounds and show a direction of designing new electron acceptor in the field of nonlinear optical materials.