【摘要】 无氯氟化学发泡剂CFA8125可与异氰酸酯反应放出CO₂气体,用于硬质聚氨酯发泡,分别使用无氯氟化学发泡剂CFA8125、第三代物理发泡剂HFC–245fa和第四代物理发泡剂LBA制备硬质聚氨酯泡沫,并对其性能进行了研究。结果表明,所得硬质聚氨酯泡沫的密度为43 kg/m³左右时,使用化学发泡剂的硬质聚氨酯泡沫在长、宽、高方向上的压缩强度分别为257,228,280 KPa,均高于使用物理发泡剂的泡沫,具有良好的压缩强度。使用化学发泡剂的硬质聚氨酯泡沫在–160℃时的热导率为10.10 mW/（m·K）,较使用物理发泡剂的硬质聚氨酯泡沫低20%左右,更具保温效果,且–196℃下的尺寸稳定性优良,符合使用标准,可适用于深冷环境保温。更多还原

【Abstract】 Chlorine-free and fluorine-free chemical blowing agent CFA8125 can react with isocyanate to release CO₂ gas for rigid polyurethane foaming.Use chlorine-free and fluorine-free chemical blowing agent CFA8125,third-generation physical blowing agent HFC–245fa and fourth-generation physical blowing agent LBA respectively were used to prepare rigid polyurethane foam and its performance were studied.The results show that when the density of rigid polyurethane foam is about 43 kg/m³,the compressive strength of rigid polyurethane foam with chemical foaming agent in the direction of length,width and height are 257,228,280 kPa respectively,which is higher than that of physical foaming agent,and has good compressive strength.The thermal conductivity of rigid polyurethane foam with chemical foaming agent is 10.10 mW/（m·K） at–160℃,which is about 20% lower than that of rigid polyurethane foam using physical foaming agent,and has better thermal insulation effect,and the dimensional stability is excellent at–196℃.It meets the standards of application and can be applied to heat preservation in cryogenic environment.更多还原