European Polymer Journal vol:29 issue:7 pages:975-979
The synthesis and second harmonic coefficients, d33, and d31 as well as the related susceptibilities, chi(zzz)(2), of two new series of (NLO-dye methacrylate)-(methyl methacrylate) copolymers were investigated. The NLO-chromophores bound covalently to the polymer chain were 4-nitro-4'-dialkylamino-alpha-cyano-stilbene, 4-nitro-4'-dialkylamino-stilbene. Thin films were obtained by spin-coating and poled by a positive corona discharge using a needle electrode in order to induce noncentrosymmetry into the systems. Nonlinear susceptibilities, chi(zzz)(2), of the films were derived from the analysis of full-angle Maker fringe patterns at 1064 nm. Chi(zzz)(2) values as high as 3.2 . 10(-7) esu could be measured.