Synthesis and Characterization of Soluble and Thermally Stable Poly(ether–imide–urea)s
作者:Hojjat Toiserkani
DOI:10.1246/bcsj.20130330
日期:2014.5.15
Two series of new modified poly(ether–imide–urea)s, POa–POc and PSa–PSc, with benzoxazole or benzothiazole pendent groups were successfully synthesized by diphenyl azidophosphate (DPAP)-activated one-pot polyaddition reaction of two bis(imide–dicarboxylic acid)s, 2-[3,5-bis(4-trimellitimidophenoxy)phenyl]benzoxazole (1O) or 2-[3,5-bis(4-trimellitimidophenoxy)phenyl]benzothiazole (1S) with various kinds of aromatic diamines a–c. In this direct method, the polymers were prepared by polyaddition reactions of the in situ-formed diisocyanate with the aromatic diamines. For comparative purposes, reference poly(ether–imide–urea)s, PRa–PRc, were also prepared by reacting a bis(imide–dicarboxylic acid) lacking pendent groups, namely, 3,5-bis(4-trimellitimidophenoxy)benzene (2) with the same diamines under similar conditions. Characterization of polymers was accomplished by inherent viscosity measurements, FTIR, 1H NMR spectroscopy and thermogravimetry. The polymers were obtained in quantitative yields with inherent viscosities between 0.19 and 0.37 dL g−1. The solubilities of modified poly(ether–imide–urea)s in common organic solvents as well as their thermal stability were enhanced compared to these of the corresponding unmodified poly(ether–imide–urea)s. The glass-transition temperature, 10% weight loss temperature, and char yields at 800 °C were, respectively, 7–28, 14–38 °C, and 3–7% higher than those of the reference polymers in nitrogen atmosphere.
通过将2-[3,5-双(4-三甲基咪唑苯氧基)苯基]苯并恶唑(1O)或2-[3,5-双(4-三甲基咪唑苯氧基)苯基]苯并噻唑(1S)与各种芳香族二胺a-c进行二苯基叠氮磷酸(DPAP)活化的单锅聚加成反应,成功合成了两种新的改性聚(醚-酰亚胺-脲)系列,即POa-POc和PSa-PSc,它们带有苯并恶唑或苯并噻唑的悬垂基团。在这种直接方法中,聚合物是通过原位形成的二异氰酸酯与芳香族二胺的聚加成反应制备的。为了进行比较,还通过在类似条件下将一种不含悬垂基团的二(酰亚胺-二羧酸)即3,5-双(4-三甲基咪唑苯氧基)苯(2)与相同二胺反应,制备了参考聚(醚-酰亚胺-脲)PRa-PRc。通过固有粘度测量、FTIR、1H NMR光谱和热重分析对聚合物进行了表征。所获得的聚合物的定量收率在0.19和0.37 dL g-1之间。