Acrylate-methylmethacrylate copolymers have been synthesized for nonlinear optical applications. Acrylate monomer units are characterized by the presence in the side chain of phenylbenzoxazole groups containing electron donor-electron acceptor substituents. The phase behavior of all polymers has been investigated by DSC, X-ray diffraction and polarizing microscopy: two of them exhibit liquid crystalline behavior of smectic type. For four polymers, nonlinear optical properties have been examined by second harmonic generation measurements on thin films (1 mm thickness) electrically poled by corona discharge. Second order susceptibility coefficients d33 and average relaxation times <t>, relative to the time stability of the chromophore poling, have been measured.