Polymer blends between polyaniline (PANI) nano/large particles and chloroprene rubbers were fabricated and investigated as the electroresponsive materials. The effects of the chloroprene type, particle size, particle concentration, and electric field strength on the electrical properties, the storage modulus sensitivity, and the dielectrophoresis force were studied. Chloroprene W provides the highest storage modulus sensitivity at 55% and is chosen as the matrix. The electrical conductivity and the dielectric constant of the blends increase with an increasing concentration of PANI nano/large particles. The storage modulus of the blends (with and without the electric field) increases linearly with the PANI content. The maximum storage modulus sensitivities of the blends with PANI nano and large particles at E = 2 kV/mm are 73% at 0.01 vol% and 63% at 0.1 vol%, respectively. The dielectrophoresis force of all specimens increases monotonically with increasing electric field strength. The blends with PANI-nano and large particles at 0.01 vol% generate higher dielectrophoresis forces than those of the pure chloroprene W. For the 0.1 vol% of PANI nano and large particles, the resultant deflection angle and dielectrophoresis forces are lower than those of the 0.01 vol% systems and the pure chloroprene W, presumably due to the diminishing resultant dipole moments generated with increasing PANI concentration. (c) 2012 Wiley Periodicals, Inc. Adv Polym Techn 32: E556E571, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/adv.21301