The foams based on TPU with high hardness were prepared by temperature rising foaming. The effects of hardness on thermal behavior, mechanical and rheological properties, gas solubility and diffusivity of TPU were discussed. It was found that TPU with higher hardness have lower CO₂ solubility and smaller diffusivity. TPU foamed sheets with various expansion ratio and cellular morphology were fabricated using different foaming parameters. It was easier to prepare TPU foams with low density for TPU with higher hardness. At suitable foaming temperatures, foams with similar density but different cell sizes could be prepared by altering saturation pressures. Finally, the hardness of the foamed samples was systematically compared. It was demonstrated that the hardness of TPU foams was affected by foam density, resin hardness and cell structure.

采用升温发泡法制备高硬度TPU基泡沫材料。讨论了硬度对 TPU 的热行为、机械和流变性能、气体溶解度和扩散率的影响。发现硬度较高的TPU具有较低的CO ₂溶解度和较小的扩散率。使用不同的发泡参数制造具有不同膨胀比和蜂窝形态的 TPU 发泡片材。具有较高硬度的 TPU 更容易制备低密度的 TPU 泡沫。在合适的发泡温度下，可以通过改变饱和压力制备具有相似密度但不同泡孔尺寸的泡沫。最后，系统地比较了泡沫样品的硬度。结果表明，TPU 泡沫的硬度受泡沫密度、树脂硬度和泡孔结构的影响。