Synthesis of novel single-walled carbon nanotubes/poly (p-phenylene benzobisoxazole) nanocomposite

Poly (p-phenylene benzobisoxazole) (PBO) fibers are some of the strongest organic polymer fibers. However, the introduction of single-walled carbon nanotubes (SWNT) into the PBO backbone might lead to improvements in their alignment and physical properties. Therefore, SWNT was cut and functionalized by three oxidative cutting methods. After cutting, three different types of SWNT were obtained. Furthermore, copolymerization of SWNTs with PBOpolymer was successfully carried out in a mixed solvent of polyphosphoric acid and methanesulfonic acid. The SWNTs were homogeneously distributed throughout the films of copolymerized products, as determined by Raman spectroscopy. The benzoxazolemoieties could be formed between the carboxyl of SWNTs and o-aminophenol derivatives of PBO polymer. The length of SWNTs affected the dispersion and reaction activity. Short SWNTs could react with the PBO polymer more easily and form more covalent bonds.