FLUOROPOLYMER BINDERS FOR CARBON NANOTUBE-BASED TRANSPARENT CONDUCTIVE COATINGS

摘要

This invention relates to flexible, transparent and conductive coatings and films formed using carbon nanotubes (CNT) and, in particular, single wall carbon nanotubes, with polymer binders. Preferably, coatings and films are formed from carbon nanotubes applied to transparent substrates forming one or multiple conductive layers at nanometer level of thickness. Polymer binders are applied to the CNT network coating having an open structure to provide protection through infiltration. This provides for enhancement of properties such as moisture resistance, thermal resistance, abrasion resistance and interfacial adhesion. Polymers may be thermoplastics or thermosets, or a combination thereof. Polymers may also be insulative or inherently electrical conductive, or any combination of both. Polymers may comprise single or multiple layers as a basecoat underneath a CNT coating, or a topcoat above a CNT coating, or combination of the basecoat and the topcoat forming a sandwich structure. A fluoropolymer containing binder, which is a solution of one fluoropolymer or a blend of fluoropolymers, which may be formulated with additives, is applied onto a carbon nanotube-based transparent conductive coating at nanometer level of thickness on a clear substrate such as PET and glass. The fluoropolymers or blend can be either semi-crystalline (with low level of crystallinity) or amorphous, preferably to be amorphous with low refraction index. Binder coating thickness can be adjusted by changing binder concentration, coating speed and/or other process conditions. This binder coating significantly improves optical transparency, and also maintain or increases conductivity of the CNT-based coating. With other benefits such as abrasion, thermal and moisture resistance, this binder coating and the resulting products is used for display and electronic applications.