Tricyanoquinodimethane-derived chromophores for second-order nonlinear optical polymers

The tricyanoquinodimethane group is one of the strongest pi-acceptors known to date. Yet it has not been employed as an acceptor in NLO chromophores with common aromatic pi-bridges. As an easily accessible example 7-(4-di-n-butylaminophenyl)-7,8,8-tricyanoquinodimethane is examined with respect to thermal/chemical stability and nonlinear optical efficiency. A derivative bearing an hydroxyethyl-spacer was synthesized and covalently attached to functionalized polyimides in a polymer analogous reaction. The second harmonic generation coefficients (d(33)) of the resulting nonlinear optical polymers were measured using the Maker-fringes experiment.