Abstract Introducing hydroxyl (OH) groups onto the surface of chemically inert hexagonal boron nitride (h-BN) is conducive to the exfoliation and functionalization of h-BN, meanwhile could enhance the intermolecular forces with polymer as well. However, chemical inertness generated by partially ionized B N bonds makes the introduction of OH groups still remains a challenge. Here, we reported a scalable one-step thermal calcination method for the fabrication of OH-functionalized h-BN nanosheets (OH-BN). Then, transparent, strong, and flexible as well as flame retardant nanocomposite films of as-prepared OH-BN and PVA were prepared through an aqueous solution casting technique. Due to hydrogen-bond self-assembly and crystalline-region self-relief, elongation at break, tensile strength, and Young's modulus of PVA nanocomposite film were simultaneously increased by 109.3%, 73.6%, and 144.4% with as low as 0.2 wt % OH-BN. Besides, the self-stiffness phenomenon that damages the material elasticity during dynamic service process of PVA nanocomposite films was effectively hindered. Meanwhile, the superior visible light transmittance and higher absorption quality to UV-light were also confirmed, which promoted its practical use in artificial cornea materials. Attributing to the well-dispersed state and layered structure, incorporated OH-BN presented a barrier function to suppress the delivery of thermal degradation products of PVA matrix, thus enhancing thermal stability and fire safety. Herein, we come to a conclusion that the scalable one-step synthesis of OH-BN and environmentally friendly fabrication of PVA/OH-BN nanocomposite films as well as excellent properties greatly contribute to the development of the practical application of h-BN nanosheets, thus obtaining multifunctional composite materials.

中文翻译：

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用于获得多功能聚乙烯醇纳米复合薄膜的羟基化氮化硼纳米片的可扩展一步合成：多方位性能改进

摘要 在化学惰性的六方氮化硼（h-BN）表面引入羟基（OH）基团有利于h-BN的剥离和功能化，同时也可以增强与聚合物的分子间作用力。然而，部分电离的 BN 键产生的化学惰性使得引入 OH 基团仍然是一个挑战。在这里，我们报道了一种可扩展的一步热煅烧方法，用于制造 OH 功能化的 h-BN 纳米片（OH-BN）。然后，通过水溶液浇铸技术制备了所制备的 OH-BN 和 PVA 的透明、坚固、柔韧以及阻燃的纳米复合薄膜。由于氢键自组装和结晶区自释放，断裂伸长率、拉伸强度和杨氏 PVA 纳米复合薄膜的 s 模量同时增加了 109.3%、73.6% 和 144.4%，而低至 0.2 wt% 的 OH-BN。此外，有效抑制了PVA纳米复合薄膜动态服役过程中破坏材料弹性的自僵现象。同时，也证实了其优越的可见光透射率和对紫外光的更高吸收质量，促进了其在人造角膜材料中的实际应用。由于其良好的分散状态和层状结构，掺入的OH-BN具有阻隔功能，可抑制PVA基体热降解产物的传递，从而提高热稳定性和防火安全性。在此处，