Synthesis Of PAMAM Dendrimer-Encapsulated Silver Nanoparticles And Antibacterial Activity On Cotton Fabric

Polyamidoamine(PAMAM) dendrimers with generation0.5to3.0were synthesized by methylacrylate and ethlenediaminean hydrous.Weused PAMAM as the template,sodium borohydride as the reducing agentrestoring the silver nitratein methanol solution to synthesis silvernanoparticles antibacterial agent.After that cotton fibers were selectiveoxidated by sodium periodate, then the silver nanoparticles antibacterialagent were grafted to the the cotton fibers which were detectedantibacterial properties by the zone of inhibition experiments andvibration flask experiments.Methyl acrylate and ethylenediamine as reactant,0.5G-3.0Gdendrimer were synthesized by repeatedly the Michael addition reactionand amidation. Best synthesis conditions which were determined bysingle factor test of0.5G and1.0G were as follows:ethylenediamine andmethyl acrylate feed ratio of1/8,the reaction temperature is30℃, thereaction time is24hours;0.5G dendrimer with methyl acrylate molarratio of1/14, the reaction temperature is30℃, the reaction time is30hours.Prepared dendrimers were used as the template, we discussed theeffect of the diameter, volume, and the dispersion of the silvernanoparticles in different generation of the dendrimer, the solvent, the molar ratio of the dendrimer as well as the quality of the added oxalicacid. The controllable of the silver nanocluster came true.Finishing the silver nanoparticle antimicrobial agent on the cottonfiber selective oxidating by the sodium periodate. Observing themorphology of the cotton fiber before and after finishing by scanningelectron microscopy. The cotton fiber were finished by the antibacterialagent with different diluted concentrations and different particle sizes ofsilver nanoparticles. The zone of inhibition experiments and shock flaskexperiments were used to discuss the antibacterial effect and washingperformance. The results show that, when diameter is7nm, the diluteconcentrate is4%, even after25times washing, their antibacterial rate isstill higher than90%.