Electrically conductive polymer composites filled with carbon black have been studied for decades in a variety of sensor and shielding applications. Despite significant advances, these systems remain plagued by high processing viscosity and brittle mechanical behavior due to the high carbon black loading required for sufficient electrical conductivity.
Using layer-by-layer (LbL) assembly from low viscosity aqueous mixtures containing carbon black and polyelectrolytes, dense composite films containing > 45 wt% CB are produced that are less than one micron thick and exhibit electrical conductivity of more than 2 S/cm or less than 500 ohm/square sheet resistance (Carbon 2006 and Synthetic Metals 2007). Even with such a high concentration of carbon black these films remain very flexible.
The LbL deposition process is a route to creating low-cost conductive films that may be used in a variety of sensing and shielding applications. These films can be processed using traditional photolithography (Electroanalysis 2007).
Intrinsically conductive polymers, such as PEDOT-PSS have also been deposited in conjunction with nano-TiO2 particles to impart UV-protection (Langmuir 2008). ICPs typically show increasing resistance when exposed to UV light due to damage done to their conjugated structure, but the addition of this colloidal protection enhances UV stability and simultaneously improves transparency without hurting electrical conductivity.