聚氨酯U001红油宽温域老化特性的试验研究

国内外对聚氨酯耐15号红油老化特性的研究较少, 开展不同老化温度和时间下聚氨酯密封材料性能演化的研究具有重要意义. 依据GB/T 1690-2010开展聚氨酯U001红油宽温域老化特性试验研究, 分析聚氨酯U001宏观力学性能及微观官能团随老化温度和时间的变化规律, 揭示宽温域下聚氨酯U001的红油老化机理. 结果表明, 聚氨酯U001红油老化过程伴随内部溶胀和氧化反应, 导致聚氨酯内部交联密度降低, 氢键数量减少, 质量变化率不断上升, 应力-应变特性变差, 拉伸强度、压缩永久变形等力学性能参数随之下降, 其中以压缩永久变形性能下降最为明显; 聚氨酯U001可在工作温度≤55℃时长期使用, 在工作温度为70℃时仅可短时间使用.

Experimental research on red oil aging characteristics of polyurethane U001 in a wide temperature range

Few studies have been conducted on the No. 15 red oil aging resistance of polyurethane both at home and abroad. It is of great significance to carry out research on the performance evolution of polyurethane sealing materials under different aging temperature and time. The wide-temperature red oil aging characteristics test of polyurethane U001 was performed according to GB/T 1690-2010. The changing rules of macro-mechanical properties and micro-functional groups of polyurethane U001 with aging temperature and time were analyzed, and the red oil aging mechanism of polyurethane U001 in a wide temperature range was revealed. The results show that the red oil aging process of polyurethane U001 is accompanied by internal swelling and oxidation reactions, resulting in a decrease in the internal cross-linking density and the number of hydrogen bonds in the polyurethane. The rate of quality change continues to rise, the stress-strain characteristics become worse, and the mechanical properties such as tensile strength and compression set decrease accordingly. Among them, the compression permanent deformation performance declines most obviously. Polyurethane U001 can be used for a long time when the working temperature is less than or equal to 55℃, and can only be used for a short time when the working temperature is 70℃.