Single-side polypyrrole coated conductive and flexible polyurethane films

Area of Science:

• Materials Science
• Polymer Chemistry

Background:

• Conductive polymer composites are essential for flexible electronics.
• Polyurethane (PU) films offer excellent stretchability.
• Existing methods for coating PU with polypyrrole (PPy) often result in two-sided coatings.

Purpose of the Study:

• To synthesize a novel single-side PPy coated PU composite film.
• To investigate the properties of this new composite as an alternative to two-side coated films.
• To characterize the morphology, conductivity, and mechanical properties of the PU/PPy composite.

Main Methods:

• Chemical oxidative polymerization of pyrrole (Py) at the acetonitrile (ACN)/water interface.
• Single-side coating of PU films using aqueous Py solution and cerium ammonium nitrate (CAN) in ACN.
• Characterization using four-point probe conductivity, FTIR, DSC, SEM, and mechanical testing.

Main Results:

• Successfully synthesized single-side PPy coated PU composite films (PU/PPy or PUP).
• Determined PPy coating thickness of 16 μm.
• Achieved a glass transition temperature (T_g) of -60.38 °C.
• Obtained a maximum conductivity of 3.5 × 10^-4 S cm^-1 on the PPy-coated side, with the back side remaining insulating.

Conclusions:

• The single-side coating method provides a viable alternative to traditional two-side coating techniques.
• The developed PU/PPy composite exhibits selective conductivity, maintaining the insulating properties of the uncoated side.
• This material holds potential for applications requiring localized conductivity in stretchable substrates.