An emulsion polymer (i.e., latex) has been used as the polymer matrix starting material in order to lower the percolation threshold of single-walled-carbon-nanotube (SWNT)-filled polymer composites (e.g., see Figure). A percolation threshold below 0.04 wt.-% SWNT is achieved. This composite system offers the potential for conductive polymers that are relatively inexpensive, mechanically robust, environmentally stable, and easy to process.