Abstract:

In order to develop a kind of low toxicity, high efficiency and broad spectrum natural antibacterial agent ued for antimicrobial finishing of medical nonwovens, the antimicrobial mug wort oil-chitosan microcapsules were prepared by emulsion crosslinking. The effect of mass ratio of mug wort oilto chitosan, volume ratio of water continuous phase to oilouter phase, speed of stirring on the appearance mouphology and size of the microcapsules was investigated. The microcapsules were characterized by scanning electron microscopy, Fourier tansfer infrared red and a laser particle size analyzer. The results show that the optimal conditions are mass ratio of mug wort oilto chitosan of 2:1, volume ratio of water continuous phase to oilouter phase of 1:5, and the stirring speed of 800r/min. The size of microcapsules is 800 - 1 800 nm, and the particle size distribution is narrow. When the mass concentrations of the microcapsules, the surfactant, 2D resin and magnesium chloride are 20 g/L, 2.0 g/L, 120 g/L and 28 g/L, respectively, and the drying temperature is 50℃. The finished samples show the antibacterial rate of Staphylococcus aureus and Escherichia coli reached 96.66% and 98.88%, respectively.

Key words: chitosan microcapsule, antimicrobial finishing, emulsion crosslinking, nonwoven fabric, natural antibacterial agent