The formation of intra- or intermolecular hydrogen bonding and their influences on polybenzoxazine’s properties were investigated after the model benzoxazine monomers (o-AB-fbz, o-AF-fbz, o-AP-fbz, p-AB-fbz, p-AF-fbz, p-AP-fbz) were synthesized. Because of the different electron-donating abilities of bridging units (benzene, furan and pyridine) in isophthalic acid (IPA), 2,5-furandicarboxylic acid (2,5-FDCA) and 2,6-pyridinedicarboxylic acid (2,6-PDCA), the strength of intramolecular H-bonding involved with the oxygen atom in oxazine ring in o-AB-fbz, o-AF-fbz and o-AP-fbz followed the order of o-AB-fbz > o-AF-fbz > o-AP-fbz, and the strength of the overall H-bonding was arranged as follows: o-AB-fbz < o-AF-fbz < o-AP-fbz. While more intermolecular H-bonding was formed in p-AB-fbz and p-AF-fbz as well as p-AP-fbz. DSC and FT-IR results discovered the relationship between the H-bonding involved with the oxygen atom in oxazine ring and the curing activities of benzoxazines. After curing reaction, the cured systems showed varied glass transition temperature (T_g), and the influence of H-bonding on T_g was revealed by in situ FT-IR analysis. Molecular dynamics (MD) simulation was also applied to investigate the properties of synthesized polybenzoxazines and similar results were obtained. Not only the formation of H-bonding but also their effects on both the curing behaviors of benzoxazine monomers and the thermal properties of cured resins were systematically investigated, which would help us understand polybenzoxazines more deeply and might be a guideline for improving their comprehensive properties only by manipulating the H-bonding.

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氢键相互作用如何影响聚苯并恶嗪的性能？与计算机仿真相结合的实验研究

在模型苯并恶嗪单体（o -AB-fbz，o -AF-fbz，o -AP-fbz，p -AB-fbz，p -AF之后，研究了分子内或分子间氢键的形成及其对聚苯并恶嗪性能的影响。-fbz，p -AP-fbz）被合成。由于间苯二甲酸（IPA），2,5-呋喃二甲酸（2,5-FDCA）和2,6-吡啶二甲酸（2,6- PDCA），与o -AB-fbz，o -AF-fbz和o -AP-fbz中恶嗪环中的氧原子有关的分子内H键强度遵循o -AB-fbz> o -AF-fbz> o -AP-fbz，整个H键的强度安排如下：o -AB-fbz < o -AF-fbz < o -AP-fbz。虽然在p -AB-fbz和p -AF-fbz以及p -AP-fbz中形成了更多的分子间氢键。DSC和FT-IR结果发现与恶嗪环中的氧原子有关的H键与苯并恶嗪的固化活性之间存在关系。固化反应后，固化体系显示出不同的玻璃化转变温度（T _g），并且氢键对T _g的影响通过原位FT-IR分析揭示。分子动力学（MD）模拟也用于研究合成的聚苯并恶嗪的性质，并获得了相似的结果。不仅系统地研究了氢键的形成，而且还研究了它们对苯并恶嗪单体的固化行为和固化树脂的热性能的影响，这将有助于我们更深入地了解聚苯并恶嗪，并且可能仅作为改善其综合性能的指南。通过操纵H键