Abstract Graphene/polyurethane (PU) porous composites combined the advantages of graphene and PU with high flexibility, electromagnetic shielding as well as fine flame retardant properties were prepared by a simple one-pot process. Graphene/PU composites with the density of 29.5 kg/m3 exhibited polygonal cell structure, which facilitated the multiple reflection attenuation of electromagnetic waves. The transmittance of the resulting composites to near infrared and mid-infrared bands was close to 0%, while the electromagnetic interference (EMI) shielding effectiveness (SE) reached 30 dB at low frequency band. The addition of flexible graphene sheets improved the flame retardancy and the flexibility of polyurethane. The peak heat release rate (PHRR) reduced from 518 to 395 kW/m2, and the elongation at break reached 300%, which was recoverable. The introduction of graphene increased the thermal degradation temperature of PU and played a positive role in the thermal stability of graphene/PU composites. These ultra-light porous composites with high flexibility, EMI shielding and fine flame retardancy showed potential in the fields of flexible electronics and stealth materials.

中文翻译：

---

具有改进的电磁屏蔽和阻燃性的含石墨烯的柔性聚氨酯多孔复合材料

摘要 通过简单的一锅法制备了石墨烯/聚氨酯（PU）多孔复合材料，结合了石墨烯和聚氨酯的优点，具有高柔韧性、电磁屏蔽和优良的阻燃性能。密度为 29.5 kg/m3 的石墨烯/PU 复合材料表现出多边形单元结构，有利于电磁波的多次反射衰减。所得复合材料对近红外和中红外波段的透射率接近 0%，而电磁干扰 (EMI) 屏蔽效率 (SE) 在低频段达到 30 dB。柔性石墨烯片的加入提高了聚氨酯的阻燃性和柔韧性。峰值放热率（PHRR）从518 kW/m2降低到395 kW/m2，断裂伸长率达到300%，可恢复。石墨烯的引入提高了PU的热降解温度，对石墨烯/PU复合材料的热稳定性起到了积极的作用。这些具有高柔韧性、EMI屏蔽性和良好阻燃性的超轻多孔复合材料在柔性电子和隐身材料领域显示出潜力。