New diamine, 4-(4-diphenylphosphino)phenyl-2,6-bis(4-aminophenyl)pyridine, was prepared, and the related polyamides (PAs) bearing 2,6-diphenylpyridyl units and pendant diphenylphosphinophenyl groups were synthesized by direct polycondensation of this diamine and various aromatic diacids in N-methyl-2-pyrrolidinone (NMP) using triphenyl phosphite and pyridine as condensing agents. The resulting PAs with inherent viscosities of 0.78–1.06 dL g−1 are readily soluble in polar aprotic solvents such as NMP, N, N-dimethylacetamide, and dimethylsulfoxide as well as less polar solvents such as m-cresol and pyridine. All the PAs are amorphous and could be solution-cast into transparent, flexible, and tough films, which have tensile strengths of 68.2–88.8 MPa, tensile moduli of 1.9–2.4 GPa, and elongations at break of 5.4–10.3%. These polymer films also exhibit high optical transparence with the UV cutoff wavelength in the 361–412 nm range. These PAs display glass transition temperatures of 316–332°C, 10% mass loss temperatures of 524–553°C, and more than 48% residues at 800°C in nitrogen, respectively. Their high char yields and good limited oxygen index values ranging from 39 to 44 indicate the prepared PAs show good thermal stability and flame-retardant property.

中文翻译：

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衍生自 4-(4-diphenylphosphino) phenyl-2,6-bis(4-aminophenyl)pyridine 和各种芳香族二羧酸的新型可溶性耐热聚酰胺

制备了新型二胺4-(4-二苯基膦基)苯基-2,6-双(4-氨基苯基)吡啶，并通过直接缩聚反应合成了相关的带有2,6-二苯基吡啶基单元和侧基二苯基膦基苯基的聚酰胺(PAs)这种二胺和各种芳香族二酸在 N-甲基-2-吡咯烷酮 (NMP) 中使用亚磷酸三苯酯和吡啶作为缩合剂。所得的特性粘度为 0.78–1.06 dL g-1 的 PA 易于溶于极性非质子溶剂，如 NMP、N, N-二甲基乙酰胺和二甲亚砜以及极性较小的溶剂，如间甲酚和吡啶。所有的 PA 都是无定形的，可以通过溶液浇铸成透明、柔韧和坚韧的薄膜，其拉伸强度为 68.2-88.8 MPa，拉伸模量为 1.9-2.4 GPa，断裂伸长率为 5.4-10.3%。这些聚合物薄膜在 361-412 nm 范围内的 UV 截止波长下也表现出高光学透明度。这些 PA 的玻璃化转变温度分别为 316-332°C，10% 的质量损失温度为 524-553°C，在 800°C 的氮气中残留超过 48%。它们的高炭产率和良好的有限氧指数值范围从 39 到 44 表明制备的 PA 显示出良好的热稳定性和阻燃性能。