새로운 방향족 폴리벤즈옥사졸 공중합체의 합성 및 특성에 관한 연구

Abstract

New aromatic Poly(hydroxyamide)s (PHAs) were prepared from 4,4‘-(2,3-quinoxalinedioxy)dibenzoic acid, 4,4‘-(2,3-pyridinedioxy)dibenzoic acid and 3,3’-dihydroxy benzidine by a direct polymerization. The PHAs were analyzed using FT-IR, ¹H-NMR, DSC, TGA and XRD. The inherent viscosites of PHAs at 35℃ in DMAc solution were in the range of 0.55∼0.83dL/g. In a survey of solubility, we checked that the PHAs were dissolved in organic solvents such as DMF, DMAc, DMSO and NMP. PHA1, 2 and 3 were slightly dissolved in the THF solvent. On the contrary, PBOs were only partially dissolved in sulfuric acid. All the PHAs exhibited strong endothermic curves in the range of 230∼300℃. The 10% weight loss degradation temperatures of PHAs were observed in the range of 317∼457℃. For PBOs, the 10% and maximum weight loss degradation temperatures were observed in the range of 616∼628℃ and 621∼653℃, respectively. The char yields of PBOs at 900℃ showed high values of 70.8∼71.8%.