벌키 그룹을 갖는 새로운 Poly(hydroxyamide)s의 합성 및 특성

Abstract

Aromatic polyhydroxyamides(PHAs) having poly(ethylene glycol)methyl ether(MPEG) group and/or ether linkages in the polymer main chain were synthesized by solution polycondensation at low temperature. PHAs were studied by FT-IR, 1H-NMR, DSC, TGA, XRD, Dynamic Mechanical Analyzer(DMA), Universal Testing Machine(UTM) and Limiting Oxygen Index(LOI). The inherent viscosities of the PHAs measured at 35 ℃ in DMAc solution were in the range of 0.68～1.49 dL/g. Solubility of PHAs was soluble or partially soluble in Tetrahydrofuran(THF) and Trifluoroacetic acid(TFA), and pyridine as well as aprotic solvents, but the PBOs were nearly insoluble in a variety of solvents. PHAs were converted to polybenzoxazoles(PBOs) by thermal cyclization reaction and endothermic peak by thermal cyclization was observed in the range of 210∼350 ℃. The 40% weight loss temperature of the PHAs showed in the range of 414∼777℃, and PBOs except for PBO 1 showed in the range of 424∼628 ℃. Char of PHAs and PBOs showed high values in the range of 24∼56%, and 35∼64%. Storage modulus of PHAs was decreased as increasing chain of MPEG. Initial modulus and Tensile strength of the PHAs were showed in the ranges of 0.12～0.22 GPa, and 2.24～3.43 MPa, which were increased with increasing mole ratio of quinoxaline. The LOI values of PHAs were increased with mole ratio of quinoxaline.