Influence of depositing nano-SiO2 particles on the surface microstructure and properties of jute fibers via in situ synthesis

Jute fibers are finding much interest as the reinforcement of polymer composites. However, surface flaws not only affect the properties of jute fibers, but also lead to the interfacial defects of jute fiber reinforced composites. This study aims to improve the properties of jute fibers, the surface flaws of which were filled up by nano-SiO2 particles via in situ synthesis. The waxy substance covering on jute fibers was removed by alkali pre-treatment, ethanediamine/alkali pre-treatment and acid/alkali pre-treatment, respectively. The acid/alkali pre-treatment was the most effective method among three pre-treatments. The nano-SiO2 particles deposition was prepared by the sol-gel technique. The results showed that the surface flaws of jute fibers could be filled up by nano-SiO2 particles with the tetraethylorthosilicate (TEOS) concentration of 0.015 mol/L. Compared with acid/alkali pre-treated fibers, the surface free energy and tensile strength of nano-SiO2 deposited fibers were increased by 11.7% and 17.9%, respectively. Moreover, the presence of nano-SiO2 particles contributed to the significant enhancement on the thermal stability of jute fibers.