Unique UV-resistant and surface active aramid fibers with simultaneously enhanced mechanical and thermal properties by chemically coating Ce0.8Ca0.2O1.8 having low photocatalytic activity

Abstract

To conquer the inferior UV resistance and poor surface activity without sacrificing the outstanding integrated performance of aramid fiber (KF) is still a challenge. A series of unique modified KFs coated with CaO doped CeO₂ (Ce_0.8Ca_0.2O_1.8), Ce_0.8Ca_0.2O_1.8@KF, were prepared, and their structures and properties were systematically investigated. Results show that the morphology of Ce_0.8Ca_0.2O_1.8@KF can be controlled by adjusting the concentration of Ce_0.8Ca_0.2O_1.8 coated on the surface of KF, so does the integrated performances of fibers; while the chemical and crystal structures of Ce_0.8Ca_0.2O_1.8@KF are nearly the same as those of KF. Attractively, all Ce_0.8Ca_0.2O_1.8@KFs not only have greatly improved UV-resistance and surface activity, but also exhibit enhanced mechanical and thermal properties. The surface free energies of Ce_0.8Ca_0.2O_1.8@KFs are 1.2–1.4 times those of KFs; and the retentions of tenacity of Ce_0.8Ca_0.2O_1.8@KFs after 168 h UV irradiation depend on the loading of Ce_0.8Ca_0.2O_1.8 on the surface of KF, but all of them are as high as 88–95%. The origin behind this is intensively discussed. This investigation provides an effective method to overcome the bottle-necks of KFs.