聚氨酯缓冲材料在2种典型环境下的耐候性研究

目的 研究聚氨酯缓冲材料在湿热海洋和干热沙漠环境下的老化性能。方法 将3种不同表观密度的聚氨酯缓冲材料在万宁和敦煌试验站进行1 a的自然环境试验，探究聚氨酯缓冲材料外观、静态压缩性能、压缩永久变形性能和红外光谱的变化。结果 在1 a的自然环境试验中，材料压缩强度先增大后降低，压缩永久变形逐渐增大；在万宁试验站，样品表面出现发霉现象，密度为25、30、40 kg/m³的聚氨酯缓冲材料的压缩强度分别增大或衰减至106.4%、93.3%、87.5%，压缩永久变形分别增大109%、98%、138%；在敦煌试验站，密度为25、30、40 kg/m³的聚氨酯缓冲材料的压缩强度分别增大或衰减至106.4%、98.2%、97.8%，压缩永久变形分别增大55%、74%、93%。结论 聚氨酯缓冲材料在自然环境中会发生水解和热氧降解等老化反应，使材料性能出现下降。材料表观密度越大，性能衰减越快。材料对于湿热海洋环境更敏感，在万宁站的老化程度大于敦煌站。

Weather Resistance of Polyurethane Cushioning Materials in Two Typical Environments

The work aims to study the aging performance of polyurethane cushioning material in hot humid ocean and hot dry desert environments. Through a one-year natural environment experiment of three different apparent densities of polyurethane cushioning materials at Wanning Test Station and Dunhuang Test Station, the appearance, static compression performance, compression set performance and infrared spectrum changes of polyurethane cushioning materials were explored. The results showed that the compressive strength of the material first increased and then decreased, and the compression set gradually increased; In Wanning Test Station, the surface of the sample showed mildew. The compressive strength of polyurethane cushioning materials with densities of 25, 30 and 40 kg/m3 attenuated to 106.4%, 93.3% and 87.5%, respectively, and the compression set increased by 109%, 98% and 138%, respectively; In Dunhuang Test Station, the compressive strength of polyurethane cushioning materials with densities of 25, 30 and 40 kg/m3 increased or attenuated to 106.4%, 98.2% and 97.8%, respectively, and the compression set increased by 55%, 74% and 93%, respectively. The performance of polyurethane cushioning materials will decrease due to aging reactions such as hydrolysis and thermal oxygen degradation in the natural environment. The greater the apparent density of the material, the faster the performance degradation. Thus, the aging degree of polyurethane cushioning material at Wanning Station is greater than that at Dunhuang station, and it is more sensitive to the hot and humid marine environment.