Synthesis, Structure And Properties Of PBO/SWNT Composite Fibres

PBO [poly (p-phenylene-2,6-benzobisoxazole)] fibre is a high performance fibres. It possesses super strength, super modulus and high thermal stability. It is a rigid-rod polymer and the molecular interaction is poor. This leads to fibres'defects such as the lower compressive strength and the inferiors ultraviolet radiation resistant ability. Because of these defects, PBO/SWNT composite fibres were prepared to enhance the mechanical properties and thermal stability and to improve its ultraviolet radiation resistant ability.Raw single-walled carbon nanotubes were treated with strong acid to increase the polarity functional groups on the surface of SWNTs. The products were named as SWNTs-COOH. The structure and the surface topograph of SWNTs were characterized. The results showed that the carboxyl groups were assuredly embodied on the surface of SWNTs after functionalization, which improved the solution ability in solvents.As the method was put forward, DADHB/TAP/SWNTs-COOH complex salt polymerized to PBO/SWNT composites. The synthesis of PBO/SWNT was studied and some crucial factors influencing polymerization were analyzed. The structure of PBO/SWNT composites and the DADHB/TAP/SWNTs-COOH complex salt were characterized. In addition, the single point method was employed to survey the special viscosity coefficient of PBO/SWNT composites. The results indicated that the way of SWNTs'addition and the amount of SWNTs'addition had important influences on preparing the PBO/SWNT composites.PBO/SWNT composites were spun by dry-jet spinning. The surface structure and the crystal structure of PBO/SWNT composite fibres were characterized. The thermal stability, mechanical properties and resistant ultraviolet radiation properties were analyzed. The results indicated that the surface of PBO/SWNT composite fibres was not as good as PBO fibres. The thermal stability of PBO/SWNT composite fibres was better than PBO fibres. In addition, the mechanical properities were promoted largely because of the synergy between SWNTs and PBO. When the amount of addition was 7.5mass%, the tensile strength of PBO/SWNT composite fibres was raised by 60%. At the same time, PBO/SWNT composite fibres improved its ultraviolet radiation resistant ability and expanded its application.