Abstract:

In order to solve the embedding of essential oil in antibacterial packaging, a nanofiber membrane with carboxymethyl chitosan (CMCS) as the shell and thyme essential oil as the core was prepared by an emulsion electrostatic process. The effects of viscosity, electrical conductivity and particle size of the electrospinning emulsion on nanofiber were studied. The microscopic morphology of the fiber membrane was observed by scanning electron microscopy and transmission electron microscopy. The bacteriostatic properties of the fiber membrane were tested by the inhibition zone method. The results show that carboxymethyl chitosan and poly (ethylene oxide) at a mass ratio of 9∶ 1 is used as the aqueous phase solution, thyme essential oil is used as the oil phase and Tween 80 is used as the emulsifier. When the volume ratio of the three materials is 36. 7：4：1 or 22. 8：4：1, a stable emulsion structure can be formed. Under the ectrospinning conditions of spinning solution flow rate of 0. 5 mL/ h, voltage of 16 - 24 kV and spinning distance of 11 cm, thyme essential oil is successfully coated in carboxymethyl chitosan fiber, and the adhesion phenomenon decreases with the voltage increase. The inhibition zone diameter of the core-shell nanofiber membrane for Staphylococcus aureus, Escherichia coli, Botrytis cinerea and Penicillium is 18. 2, 11. 0, 32. 5 and 29. 2 mm respectively, and the bacteriostatic effect is good.

Key words: emulsion electrospinning, core-shell structure, packaging material, carboxymethyl chitosan, thyme essential, antibacterial property