In the study, the conductive graphite flakes filled poly(urethane-imide) composites (PUI/GFs) with high performance were constructed by the thermal imidization self-foaming reaction. It was found that the foaming action could promote the redistribution of GFs during curing process and the formation of stable linear conductive pathways. The percolation threshold of PUI/GFs composites was lowered from 1.26 wt% (2000 mesh GFs) or 0.86 wt% (1000 mesh GFs) to 0.79 wt% (500 mesh GFs), which were relatively low percolation thresholds for polymer/GFs composites so far. When the content of 500 mesh GFs was 4.0 wt%, the electrical conductivity of the composite was as high as 3.96 × 10⁻¹ S/m. Also, a poly(urethane-imide) (PUI) matrix with excellent thermal stability (T_d10%: 334.97 °C) and mechanical properties (elongation at break: 324.52%, tensile strength: 15.88 MPa) was obtained by introducing the rigid aromatic heterocycle into the polyurethane (PU) hard segments. Moreover, the zero temperature coefficient of resistivity for the composites was observed at the temperature range from 30 °C to 200 °C. Consequently, PUI/GFs composites may provide the novel strategy for considerable conductive materials with high thermal stability in electrical conductivity.

在研究中，通过热酰亚胺化自发泡反应构建了高性能的导电石墨片填充聚（氨基甲酸乙酯-酰亚胺）复合材料（PUI/GFs）。发现发泡作用可以促进固化过程中GFs的重新分布和稳定的线性导电通路的形成。PUI/GFs 复合材料的渗透阈值从 1.26 wt%（2000 目 GFs）或 0.86 wt%（1000 目 GFs）降低到 0.79 wt%（500 目 GFs），这是聚合物/GFs 复合材料的相对较低的渗透阈值，因此远的。当500目GFs的含量为4.0 wt%时，复合材料的电导率高达3.96×10 ^-1  S/m。此外，聚（氨基甲酸乙酯-酰亚胺）（PUI）基质具有出色的热稳定性（T _d10%: 334.97 °C) 和机械性能（断裂伸长率：324.52%，拉伸强度：15.88 MPa）是通过将刚性芳香杂环引入聚氨酯 (PU) 硬链段中获得的。此外，在 30 °C 至 200 °C 的温度范围内观察到复合材料的电阻率温度系数为零。因此，PUI/GFs 复合材料可以为具有高热稳定性的导电材料提供新的策略。