Fabrication of mechanically robust and UV-resistant aramid fiber-based composite paper by adding nano-TiO2 and nanofibrillated cellulose

Abstract

Aramid fiber-based composite paper is widely used as an engineering material that is often used in outdoor environments. This inevitably cause ultraviolet (UV) damage to aramid fibers. In this work, nanotitanium dioxide (nano-TiO2) was introduced to endow the composite a good UV-resistance while nanofibrillated cellulose (NFC) was used to disperse and deposit TiO2 nanoparticles onto aramid fibers by physical interaction. Firstly, TiO2 nanoparticles were treated by (γ-aminopropyl) triethoxysilane to achieve abundant amino-groups (–NH2), which can interact with hydroxyl groups (–OH) of NFC. The results showed that NFC can significantly suppress nano-TiO2 aggregation and result in a well-defined core–shell structure of TiO2 nanoparticles uniformly coated onto aramid fibers. Also, the bridge effect of NFC and the reinforcing effect of nano-TiO2 benefit the mechanical properties the aramid/NFC/TiO2 composite. The maximum tensile index (~ 16.42 N m/g) and maximum tearing index (~ 9.28 mN m2/g) of aramid/NFC/TiO2 composites increase by ~ 43.4 and ~ 26.1% in comparison with the control sample (~ 11.45 N m/g and ~ 7.36 mN m2/g), respectively. Meanwhile, the aramid/NFC/nano-TiO2 composite achieves a good UV-resistant property because of the dominant light-absorbing ability of well-dispersed TiO2 nanoparticles. Therefore, our work presents a green and damage-free approach to achieve high-performance aramid fiber composite especially with great UV resistance.