NEW 3RD-ORDER NONLINEAR POLYMERS FUNCTIONALIZED WITH DISPERSE-RED ANDDISPERSE-ORANGE CHROMOPHORES WITH INCREASED STABILITY

New and very stable polymers with good optical third-order nonlinearit ies have been prepared by condensation between a copolymer of maleic a nhydride and octadecene and appropriate Disperse Red and Disperse Oran ge type chromophores. The nonlinear response of low concentration solu tions of the polymers has been determined using a new numerical Z-scan technique. The polymers have been found highly stable, and their nonl inear response is very reproducible, both under intense illumination a nd upon several repeated experiments over months. Especially the polym er where the Disperse Orange 3 chromophore is incorporated in the main chain through imide linkages displays both the highest refractive non linearity and almost no two-photon absorption. Its surprisingly higher nonlinear response with respect to the parent Disperse Orange 3 is de monstrated and discussed.