Molecular design of nanometric zinc borate-containing polyimide as a route to flame retardant materials

Zinc borate (Zn2B6O11·3H2O) nanoparticles were successfully prepared by using an emulsion liquid membrane (W/O/W emulsion) to control the size of particles with Na2B4O7·10H2O, boric acid and ZnSO4·7H2O as raw materials. All materials were dispersed with the polyimide (PI) precursor, poly (amic acid). Using a combination of dissolving the poly (amic acid) and mixing fatty acid surfactant-coated zinc borate nanoparticles; we have demonstrated the formation of nanocomposites with uniform nanoparticles dispersion. We report the first deposition of nanocomposite polyimides from solution using spin-coating. The microstructures and morphology of the as-obtained samples were studied by X-ray diffraction (XRD), infrared spectra (IR), scanning electron microscopy (SEM) equipped with an energy-dispersive X-ray spectrometer (EDX), transmission electron microscopy (TEM) and thermogravimetric analysis (TGA).