氟橡胶密封材料的湿热老化机制*

摘要

通过对氟橡胶密封材料的湿热老化试验研究，以及老化试验前后材料的红外光谱分析与压缩永久变形测量，分析老化引起材料内部的分子结构变化，建立不同老化条件下材料性能随老化时间变化规律。结果表明：温度和湿度对橡胶压缩性能的影响都很明显，温度影响更加显著；氟橡胶在不同的老化条件下具有不同的失效机制，在湿热条件下主是分子交联和水解，在热氧条件下是分子断裂和交联。要%The hygrothermal aging experiments of fluorine rubber sealing materials were carried out,and the molecular structure changes inside the material were analyzed through measuring the compression permanent deformation and investi-gating the infrared spectrum of fluorine rubber sealing materials before and after aging tests. The variation law of material properties with aging time in different aging conditions was established. The results show that both temperature and humidi-ty have avery obvious effect on the rubber compression performance,and the temperature effect is more significant. Fluorine rubber failure mechanism is different in different aging conditions:in hygrothermal conditions,it is the molecular cross-linking and hydrolysis,and in conditions of heat and oxygen,the molecular fracture and cross linking.