Organo-soluble polyimide (TBAPP–OPDA)/clay nanocomposite materials with advanced anticorrosive properties prepared from solution dispersion technique Original Research Article

A series of organic soluble polymer–clay nanocomposite (PCN) materials that consist of organic soluble polyimide (SPI) and layered montmorillonite (MMT) clay are successfully prepared by the solution dispersion technique. The as-synthesized PCN materials are characterized by infrared spectroscopy, wide-angle powder X-ray diffraction, transmission electron microscopy and scanning electron microscopy. Polymer–clay nanocomposite materials, in the form of coating, incorporating with low clay loading on cold-rolled steel (CRS) are found much superior in anticorrosion over those of bulk SPI on the basis of a series of electrochemical measurements of corrosion potential, polarization resistance and corrosion current in 5 wt% aqueous NaCl electrolyte. Effects of the material composition on the O2/H2O molecular permeability, optical clarity and thermal stability of SPI along with PCN materials, in the form of both membrane and fine powder, are also studied and compared to insoluble polyimide system prepared from the thermal imidization by molecular permeability analysis, UV–vis transmission spectra, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), respectively.