Helical polysilane wrapping onto carbon nanotube: preparation, characterization and infrared emissivity property study

A helical polysilane/multi walled carbon nanotubes composite was fabricated by wrapping helical HPS copolymer around the surface of modified nanotubes through surface oxidation. HPS was pre-polymerized by Wurtz-type coupling reaction in chloroform (CHCl3), demonstrating optical activity and adoption of a predominately signal-handed helical conformation. Various kinds of characterization including Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), transmission electron microscopy (TEM), ultraviolet-visible spectroscopy (UV-vis), thermogravimetric analysis (TGA), circular dichroism (CD) and Raman spectroscopy have been utilized to demonstrate HPS noncovalently wrapped around the nanotubes to protect their original graphite structure. The wrapped HPS exhibited enhanced thermal stability and increased optical activity after wrapping. The infrared emissivity property of the composites at 8–14 μm was investigated as well. These results indicate the HPS/f-MWNTs composites possess a much lower infrared emissivity value (ε = 0.576) than raw MWNTs, which resulted from synergistic effect of the particular helical conformation of HPS and improved interfacial interaction between the organic polymers and inorganic nanoparticles.