Abstract In this study, 4,4′-diphenylmethane diisocyanate and polytetramethylene glycol were used to prepare a prepolymer; N,N′-bis(4-hydroxybenzylidene)-2,6-diaminopyridine (BHBP) was used as a chain extender; and these elements were combined to prepare a novel polyurethane, BHBP/PU. Gel permeation chromatography revealed that the molecular weight of the BHBP/PU samples increased as the BHBP content was increased. Fourier transform infrared spectroscopy demonstrated that high BHBP content facilitated strong hydrogen bonding in the samples. Differential thermogravimetry indicated that the initial decomposition temperature of BHBP/PU-3 was approximately 10 °C higher than that of BHBP/PU-1. Differential scanning calorimetry and dynamic mechanical analysis revealed that increasing the BHBP content substantially increased both the glass transition and dynamic glass transition temperatures of the BHBP/PU samples. The tensile strengths of BHBP/PU-1, BHBP/PU-2, and BHBP/PU-3 were 7.7, 10.9, and 21.6 MPa, respectively, with corresponding Young’s moduli of 0.7, 1.9, and 3.3 MPa. These results demonstrated that both the tensile strength and Young’s modulus of the BHBP/PU samples increased as the BHBP content was increased. Moreover, the BHBP/PU samples exhibited excellent shape recovery of >90%.

中文翻译：

---

含苯甲酰基和吡啶环的席夫碱扩链剂制备形状记忆聚氨酯的合成及性能

摘要 本研究以4,4'-二苯基甲烷二异氰酸酯和聚丁二醇制备预聚物；N,N'-双(4-羟基亚苄基)-2,6-二氨基吡啶(BHBP)用作扩链剂；并将这些元素结合起来制备了一种新型聚氨酯，BHBP/PU。凝胶渗透色谱显示 BHBP/PU 样品的分子量随着 BHBP 含量的增加而增加。傅里叶变换红外光谱表明高 BHBP 含量促进了样品中的强氢键。差示热重分析表明，BHBP/PU-3 的初始分解温度比 BHBP/PU-1 高约 10 °C。差示扫描量热法和动态力学分析表明，增加 BHBP 含量会显着提高 BHBP/PU 样品的玻璃化转变温度和动态玻璃化转变温度。BHBP/PU-1、BHBP/PU-2 和 BHBP/PU-3 的拉伸强度分别为 7.7、10.9 和 21.6 MPa，相应的杨氏模量分别为 0.7、1.9 和 3.3 MPa。这些结果表明，随着 BHBP 含量的增加，BHBP/PU 样品的拉伸强度和杨氏模量都增加。此外，BHBP/PU 样品表现出>90% 的出色形状恢复。这些结果表明，随着 BHBP 含量的增加，BHBP/PU 样品的拉伸强度和杨氏模量都增加。此外，BHBP/PU 样品表现出>90% 的出色形状恢复。这些结果表明，随着 BHBP 含量的增加，BHBP/PU 样品的拉伸强度和杨氏模量都增加。此外，BHBP/PU 样品表现出>90% 的出色形状恢复。