The synthesis and characterization of new dyes, prepared in two steps from chloromethylstyrene, and containing azo moieties or stilbene are reported. All synthesized monomers show spectroscopic properties (nuclear magnetic resonance, ultraviolet) in accordance with the attempted structure. These monomers have been copolymerized with styrene and the nonlinear optical properties of the new compounds and those of previously described polymeric imines have been studied via second harmonic generation.