Preparation of carbon nanotubes as the conductive coating layer on flexible thermal-resistant substrate by permeating method and its residual stress analysis

A polyarylate (PAR) substrate was first prepared by hot pressing and then carbon nanotubes (CNTs) were coated on its surface by a low-temperature spraying method. In order to eliminate the residual stress and enhance the adhesive ability between the substrate and the coated CNT layer, an optimal thermo-permeating process is proposed. The relationship between the thickness of the permeating layer and the residual stress of coating layers was investigated. Triple-layer structure models were provided to evaluate the residual stress of coating layers. The experimental results show that if the sample was treated by the optimal thermo-permeating process, its residual stress was dramatically reduced from 1.7×10³ MPa to 0.45 Pa; meanwhile, its adhesive ability was intensively enhanced from 1B to 5B according to ASTM D3359 adhesion classifications.