Emulsion-polymerized poly(styrene-rand-butyl acrylate) (St-BA) copolymers exhibit damping capabilities over a wide temperature range with changes in the monomer ratio. Blending copolymers of different compositions results in a multiclamping peak, further widening the effective damping temperature range. Adding carbon black (CB) reduces the peak damping intensity but enhances damping at higher temperatures. The addition of dodecyl benzene sulfonic acid to an St-BA/CB aqueous dispersion improves the dispersion of CB in the polymer, reducing the percolation threshold and improving the conductivity while slightly affecting the mechanical behavior. The electrical properties of the St-BA/CB system are affected by the copolymer composition, influencing the polymer surface tension. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 115:1922-1928, 2010