Preparation Of Hydroxyl-functionalized Silver Nanoparticles And Property Of Silver Nanoparticle-loaded Chitosan Fibers

In this paper, non-ionic hydroxyl-functionalized silver nanoparticles(AgNPs) was designed in order to improve the antibacterial properties of chitosan fibers. Hydroxyl-functionalized AgNPs were applied to prepare AgNP-loaded chitosan fibers by a novel incubation-adsorption method. The adsorption ability and adsorption mechanism of AgNPs on chitosan fibers were evaluated and analyzed. It opens up a new direction for the research of chitosan fiber with load/adsorption of metal nanoparticles.Using methyl acrylate, diethanol amine and TMP as raw materials, hydroxyl-terminated hyperbranched poly(amine-ester)(HBP-OH) was synthesized by one-step method. The as-synthetic HBP-OH was then used for synthesis of non-ionic hydroxyl-functionalized AgNPs. As-prepared AgNPs were characterized by UV-vis, DLS and TEM. Results showed that as-prepared AgNPs were small size and with narrow size distribution. The average diameter determined by DLS was around 15 nm. The zeta potential test demonstrated that the surface charge of hydroxyl-functionalised AgNPs agreed well with the discipline of the non-ionic polymer capped AgNPs.The chemical resistance, temperature tolerance and antibacterial property of hydroxyl-functionalized AgNPs were studied. The results showed that hydroxyl-functionalized AgNPs had good chemical resistance and temperature tolerance. In addition, antibacterial tests showed that as-prepared AgNPs had good antibacterial activities against E.coli and S.aureus and the minimal inhibitory concentration was about 4 mg/L.The adsorption ability and adsorption mechanism of AgNPs on chitosan fibers were evaluated and analyzed using the visible spectrophotometer method. Adsorption results showed that the adsorption ability of AgNPs on chitosan fibers was very high. The adsorption capacity for AgNPs was up to 3390 mg/kg. The adsorption mechanism lied in two aspects: Electrostatic attraction and Hydrogen bonding.The microtopography, element composition and chemical structure of AgNP-loaded chitosan fibers were characterized by SEM, XRD, XPS and FTIR respectively. Finally, the antimicrobial property, mechanical property and air permeability of AgNP-loaded chitosan fibers were also studied. Results indicated that metallic AgNPs were well distributed on the surface of chitosan fibers, were not oxidized. And the chemical property of chitosan fibers also did not change. Antibacterial test showed that AgNP-loaded chitosan fibers showed excellent antibacterial property. The breaking strength of AgNP-loaded chitosan fabric were somewhat increased though not obviously, while the good permeability of chitosan fabric were not influenced by hydroxyl-functionalized AgNPs.