Unique Surface Modified Aramid Fibers With Improved Flame Retardancy, Tensile Properties, Surface Activity And Uv-Resistance Through In Situ Formation Of Hyperbranched Polysiloxane-Ce0.8ca0.2o1.8 Hybrids

It is a great challenge to endow aramid fibers (KFs) with improved flame retardancy and high mechanical properties while simultaneously overcoming their poor surface activity and UV-resistance; however, no such work has been reported to date. Herein, a new type of surface modified KF with hyperbranched polysiloxane (HSi)-Ce0.8Ca0.2O1.8 hybridized coating, HSi-Ce0.8Ca0.2O1.8@KF, was prepared through an in situ methodology. The influence of the loading of HSi-Ce0.8Ca0.2O1.8 on the structure and integrated performance of HSi-Ce0.8Ca0.2O1.8@KFs was intensively studied and compared with KF and coated fibers with HSi or Ce0.8Ca0.2O1.8. Results show that the HSi-Ce0.8Ca0.2O1.8 hybrid has a greater ability in improving flame retardancy, UV resistance and surface activity of KF; in addition, the hybrid exhibits a synergistic effect with HSi and Ce0.8Ca0.2O1.8. The peak heat release rate of HSi-Ce0.8Ca0.2O1.8@KF decreases by 47.7%. After 168 h of-UV irradiation, the retentions of the tensile strength of HSi-Ce0.8Ca0.2O1.8@KFs reach 91.9-97.4%, while the initial decomposition temperature of HSi-Ce0.8Ca0.2O1.8@KF is about 96 degrees C higher than that of KF. The origin behind the synergistic effect with HSi and Ce0.8Ca0.2O1.8 was also intensively studied.