| 초록 |
Poly(p-phenylene benzobisoxazole) (PBO) is a rigid-rod molecule with extended chain conformation. PBO fibers have very high tensile strength and modulus, but their performance under compression is known very poor. In order to improve mechanical properties of PBO fibers, nanocomposites of PBO/(multi-wall carbon nanotube (MWNT)) were synthesized by in-situ polymerization in poly(phosphoric acid) (PPA). MWNT was oxidized under ozone gas flow before making nanocomposites. It was confirmed that oxidative groups such as –OH and -COOH were introduced to MWNT by using Raman spectroscopy, X-ray Photoelectron Spectroscopy and SEM. Thus, some kinds of lateral interaction between PBO and ozone-treated MWNT was expected after heat treatment of the fibers at high temperature. PBO/MWNT nanocomposite fibers were prepared by spinning the liquid crystalline as-polymerized solution. The morphology, mechanical and thermal properties of the PBO/MWNT fibers was characterized. |
