芳纶纤维的冷等离子体处理及其老化性能

为改善芳纶纤维与树脂基体之间的黏结性，采用氮气冷等离子体技术对芳纶纤维进行改性，借助扫描电子显微镜、原子力显微镜、X射线光电子能谱仪及接触角测量仪观察和分析纤维的表面形貌、化学组分、表面润湿性及表面能的变化。结果表明：样品处理后24 h内，纤维表面粗糙度提高，C 含量减少，N 和 O 含量增加，接触角由疏水转变为亲水，表面能增大；随着放置时间的延长，纤维表面粗糙度保持不变，非极性基团C—C 和C—H 含量增加，极性基团C—N、C—O 和NH—CO 含量减少，表面能降低，接触角增大，最后趋于稳定；放置28d后，接触角比未处理纤维降低了27.8°，表面能提升了87%，表明冷等离子体对表面的刻蚀和改性是永久的。

Cold plasma treatment and aging properties of aramid fiber

In order to improve the bonding performance between aramid fiber and resin matrix, the aramid fiber was modified by cold plasma in nitrogen gas.The surface morphology, chemical composition, surface wettability and surface energy aging properties of the aramid fibers treated by nitrogen cold plasma were studied with the increase of deposition time. The fibers were observed by scanning electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy and contact angle meter. The results show that the surface roughness of the fiber obviously increases after within 24 h treatment, the content of C on the fiber surface decreases and the contents of the N and O increase. The wettability changes from the hydrophobicity to hydrophilicity. The surface energy is improved. As time increases, the fiber surface remains rough. Non-polar group C—C and C—H increase, the polar group C—N, C—O and NH—C = O decrease, and the surface energy gradually reduces with the increase of contact angle, and finally tend to be stable. After 28 d,in comparison with the untreated fiber, the contact angle of the treated fibers reduces by27.8°, and thesurface energyincreases by 87 %. This indicates that the cold plasma etching and modification of the surface are permanent.