A series of soluble polyacrylates containing different azobenzene side chains have been synthesized via atom transfer radical polymerization (ATRP) technique, from which the side-chain nonlinear optical (NLO) polymers with controllable molecular weight and low polydispersity (1.1-1.4) have been obtained. The third-order NLO absorption and refraction coefficients were simultaneously determined by Z-scan technique. The polymerization activity of the azobenzene-containing acrylate monomers and the third-order NLO properties of the obtained polyacrylates were both dominated by the electronic effect of the different substituents in the azobenzene side chain. The results of Z-scan with and without an aperture showed that all the azobenzene-containing monomers and polymers have both nonlinear absorption and nonlinear refraction. The third-order NLO susceptibility (chi((3))) of all the azobenzene-containing samples under the laser irradiation is 1.0-5.0 x 10(-11) esu. (C) 2008 Elsevier Ltd. All rights reserved.