Herein, we report significantly enhanced mechanical properties and thermal conductivity of polyimide (PI) by incorporating a small amount (0.01 wt %) of individualized boron-doped high-quality graphene as a filler. The boron-doped expandable graphite (B-EG) was synthesized by mixing boric acid (H₃BO₄) with expandable graphite (EG) and thermally treating the mixture at 2450 °C for 30 min using a graphite furnace in an argon atmosphere. The boron-doped graphene (B-g) was prepared by the solution-phase exfoliation of B-EG with an ultrasonication process, which is a method to obtain individualized graphene as well as few-layer graphene. The PI nanocomposites were prepared using the obtained graphene. The PI nanocomposites synthesized with high-quality B-graphene (B-g) showed enhanced mechanical properties and thermal conductivity compared to those of pure PI due to the doping effects and strong interfacial interactions between graphene and the PI matrix.

中文翻译：

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结合了个性化掺硼石墨烯的聚酰亚胺纳米复合材料的增强的机械性能和导热性

在本文中，我们报道了通过掺入少量（0.01 wt％）的个性化掺硼优质石墨烯作为填料，聚酰亚胺（PI）的机械性能和导热性显着提高。通过混合硼酸（H ₃ BO ₄）来合成掺硼可膨胀石墨（B-EG））和可膨胀石墨（EG），并在氩气气氛中使用石墨炉在2450°C下将混合物热处理30分钟。硼掺杂的石墨烯（Bg）是通过B-EG的固溶相剥离和超声处理制备的，这是一种获得个性化石墨烯和少层石墨烯的方法。使用获得的石墨烯制备PI纳米复合材料。与纯PI相比，由高质量B-石墨烯（Bg）合成的PI纳米复合材料显示出增强的机械性能和导热性，这归因于石墨烯与PI基质之间的掺杂效应和强烈的界面相互作用。