| 초록 |
Aromatic polyimides are well known as one of the most important classes of high performance polymers due to their excellent stability in thermal, mechanical and electrical properties and chemical resistance. In this study, a series of hydroxyl-containing polyimides (HPI) were prepared via two-step method of thermal, chemical and solution imidization of poly(amic acid)s. These polyimide precursors were cast on glass plate and treated up to 450oC under argon atmosphere to induce thermal rearrangement to polybenzoxazoles (PBO) by chain reformation and the following evolution of CO2/CH3COOH. PBO films showed excellent thermal stability than precursor polyimides and tremendous performances in their gas permeation properties as surpassing polymeric upper bound. |
