Polyurethane (PU) foam is known as the popular material for the applications in many fields of industry and life. To improve the mechanical and thermal properties of this material, in this research, PU foam was reinforced with aniline-modified multiwalled carbon nanotubes (MWCNTs). Fourier transform infrared FTIR spectrum of modified MWCNTs showed the aniline was grafted on the surface of MWCNTs through the appearance of –NH₂ stretches. The effect of MWCNTs with and without modification on the density, porosity, compressive strength, and heat conductivity of PU/MWCNT foam nanocomposites was investigated. The dispersibility of MWCNTs in the PU matrix was enhanced after modification with aniline. Compressive strength of PU nanocomposite reached the highest value after adding 3 wt.% of modified MWCNTs into PU foam. Besides, the water uptake of PU nanocomposites using 3 wt.% of MWCNTs was decreased to 13.4% as compared to that using unmodified MWCNTs. The improvement in thermal conductivity of PU/aniline-modified MWCNT nanocomposite was observed due to the change in the cellular size of PU foam in the presence of MWCNTs as shown by SEM images.

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多壁碳纳米管对聚氨酯泡沫导热性和孔尺寸的影响

聚氨酯（PU）泡沫是众所周知的工业和生活许多领域中广泛应用的材料。为了改善这种材料的机械和热性能，在这项研究中，PU泡沫用苯胺改性的多壁碳纳米管（MWCNT）增强。改性多壁碳纳米管的傅立叶变换红外FTIR光谱表明，苯胺通过–NH ₂的出现接枝在多壁碳纳米管的表面延伸。研究了改性后的MWCNTs对PU / MWCNT泡沫纳米复合材料的密度，孔隙率，抗压强度和导热性的影响。用苯胺改性后，MWCNT在PU基体中的分散性增强。将3 wt。％的改性MWCNTs添加到PU泡沫中后，PU纳米复合材料的抗压强度达到最高值。此外，与使用未改性的MWCNT相比，使用3重量％的MWCNT的PU纳米复合材料的吸水率降低至13.4％。如SEM图像所示，由于在存在MWCNT的情况下PU泡沫的泡孔尺寸的变化，观察到PU /苯胺改性的MWCNT纳米复合材料的导热率的改善。