紫外老化对聚甲醛纤维结构与性能的影响

研究了聚甲醛(POM)纤维在自然暴露老化以及在紫外老化箱中的加速老化行为,通过单纤维强力仪、扫描电镜、红外光谱仪、白度分析仪分析了老化对POM纤维结构与性能的影响。结果表明:POM纤维的耐老化性能差,自然老化8个月,抗拉强度下降22%,紫外老化14 d,抗拉强度下降84%;在光、氧的作用下,分子链发生断链的端基被氧化成羰基、羧基和羟基,黄色指数逐渐增加;通过添加抗老化母料F可显著提高POM纤维的抗老化性能。当抗老化母料F质量分数为3%、在紫外加速老化14 d时,POM纤维的抗拉强度仅下降8%,比未添加抗老化母料的POM纤维的抗拉强度提高了76%。

Effect of Ultraviolet Aging on Structure and Properties of Polyoxymethylene Fiber

The natural aging behavior of polyoxymethylene(POM) fibers and their accelerated aging behav-ior in the UV aging tank were investigated. The effect of aging on structure and properties of POM fibers hadbeen measured through a single fiber strength tester, SEM, FTIR and whiteness analyzer. The resultsshowed that the anti-aging property of POM fiber was unsatisfactory. After naturally aging for 8 months andUV aging for 14 days, the tensile strength of POM fibers decreased by 22% and 84%, respectively. Exposedin light and oxygen, the broken end groups from molecular chain would be oxidized to carbonyl groups, car-boxyl groups and hydroxyl groups, leading to a gradually increased yellow index. The aging resistance ofPOM fibers could be significantly improved by the introduction of anti-aging master batch F. When the con-tent of anti-aging master batch F reached up to 3%, the tensile strength of POM fibers only decreased by8% under UV accelerated aging for 14 days, which meant that an increment of 76% in tensile strength wasachieved compared with POM fibers without anti-aging master batch.