聚芳酯纤维的化学稳定性及其腐蚀降解

Chemical stability and corrosion degradation of polyarylester fiber

为研究聚芳酯纤维在高湿热、强腐蚀条件下的耐受性,选用酸、碱及强氧化剂处理聚芳酯纤维,并借助光学显微镜、扫描电子显微镜、差示扫描量热仪、傅里叶变换红外光谱仪及热失重分析仪等,研究纤维形态结构、聚集态结构及大分子链结构变化。结果表明:在常温和60℃下,H2SO4处理后纤维表面未见明显变化,HNO3处理后纤维仅出现少量沟槽,但经KMnO4处理后,纤维横向沟槽增多,纵向呈现微裂纹,尤其经NaOH处理后,纤维表面由沟槽变为凹坑,甚至呈腐蚀断裂状态;酸和KMnO4并未显著破坏纤维的晶区有序结构,而NaOH处理降低了纤维晶区规整度;H2SO4、HNO3和NaOH及KMnO4处理引起聚芳酯纤维大分子链苯环上-CH键断裂,导致纤维降解,残炭率降低。

In order to investigate the resistance of polyacrylester fiber to high damp heat and strong corrosion,the fibers were treated by strong acid,alkali and oxidant,and then the morphological structure,aggregation structure and macromolecular chain structure of the fibers were studied. The results show that the surfaces of fibers treated with H2SO4 show no significantly change at room temperature and 60 ℃,while only a few grooves appear in the surface of fibers treated with HNO3. However,after treatment by KMnO4,the transverse grooves of the fibers increase and the longitudinal microcracks appear. Especially after treatment by Na OH,the surface of the fibers changes from grooves to pits and even show a corrosion fracture state. Acid and KMnO4 don’t significantly destroy the ordered structure of the crystalline region,while Na OH solution reduces the regularity of the crystalline region. The breakage of -CH bond on the benzene ring of macromolecular chains occurs after treatment by H2SO4,HNO3,NaOH and KMnO4,and eventually leads to degradation of polyarylester fibers and reduction of residual ratio.