NaOH/urea solution spinning of cellulose hybrid fibers embedded with Ag nanoparticles: influence of stretching on structure and properties

Cellulose hybrid fibers embedded with silver nanoparticles (Ag NPs) were prepared from a spinning dope through a bottom-up approach. Instead of using toxic agents or high temperature, an alkaline cellulose dope was directly used as a reducing agent for in situ synthesis of Ag NPs. The regenerated cellulose fibers displayed a dense circular microstructure and Ag NPs with a mean diameter of 40.1 nm were inlaid on its surface and inside. By increasing the spinning drawing ratio, the diameter and Ag content of the nanohybrid fibers decreased while its tensile strength in dry state increased significantly. Because of the embedded structure of NPs, the width of inhibition zone for the nanohybrid fibers against S. aureus and E. coli was small. However, both bacteria could be killed within 5 h in the presence of the nanobybrid fibers. In particular, the nanobybrid fibers showed excellent antibacterial durability and low cell toxicity. Besides, it was demonstrated that the nanobybrid fibers with lower diameter showed better catalytic activity and the catalytic efficiency could reach 99.3% for methyl orange. This biosynthesis approach is expected to offer a sustainable method for scale-up fabrication of functional cellulose fibers.