Abstract This article studies the effect of carbon nanofibers (CNFs) on the morphological, thermal and mechanical properties of water-blown rigid polyurethane (PUR) foams with densities in the range of 55–60 kg/m3. Different amounts of CNF have been used, 0.1, 0.2, 0.3 and 0.4 wt% CNFs are located in the struts and produce minor modifications on open cell content, cell size, cell size distribution and anisotropy ratio of the foams. The contributions of the heat conduction mechanisms have been quantified by measuring the extinction coefficient and by modelling the thermal conductivity. The inclusion of CNFs reduces the radiative contribution by increasing the extinction coefficient and increases the conduction through the solid phase mainly due to an increase in density and an increase of the conductivity of the polymeric matrix. Due to this, a clear reduction of the heat flow by radiation and a reduction of the total thermal conductivity is achieved with only 0.1 wt% of CNFs. Moreover, the addition of this low amount of CNF allows maintaining the mechanical properties of the foams.

中文翻译：

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碳纳米纤维增强水发泡聚氨酯硬质泡沫的热导率和力学性能评价

摘要 本文研究了碳纳米纤维 (CNF) 对密度在 55–60 kg/m3 范围内的水发泡硬质聚氨酯 (PUR) 泡沫的形态、热和机械性能的影响。已经使用了不同量的 CNF，0.1、0.2、0.3 和 0.4 wt% 的 CNF 位于支柱中，并对泡沫的开孔含量、孔尺寸、孔尺寸分布和各向异性比产生微小的改变。热传导机制的贡献已经通过测量消光系数和通过对热导率建模来量化。CNF 的包含通过增加消光系数来降低辐射贡献，并增加通过固相的传导，这主要是由于聚合物基质的密度增加和电导率增加。由于此，仅使用 0.1 wt% 的 CNF 就可以通过辐射明显减少热流并降低总热导率。此外，添加这种少量的 CNF 可以保持泡沫的机械性能。