Continuous preparation and antibacterial mechanisms of biodegradable polylactic acid/nano-zinc oxide/additives antibacterial non-wovens

Biodegradable polylactic acid (PLA)/nano‑zinc oxide (ZnO)/additives non-woven slices were prepared by melt blending method. The effects of antibacterial agent nano-ZnO, antioxidant pentaerythrityl tetrakis-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionate (1010), and chain extender multi-functional epoxy (ADR), on the melt flow rate, mechanical properties, thermal stabilities and micromorphology of the slices were investigated. The melt flow rate decreased from 26.94 g/10 min to 17.76 g/10 min, and the tensile strength increased from 10.518 MPa to 30.427 MPa with the increase of nano-ZnO and additives content. The slices were further spunbonded. The wettability and antibacterial properties of PLA/nano-ZnO/additives antibacterial non-wovens were studied, and the antibacterial action mechanism was clarified. The results showed that the biodegradable PLA/nano-ZnO/additives antibacterial non-wovens were prepared continuously successfully. The prepared non-woven fabrics exhibited good hydrophobicity and antibacterial properties. The mechanism study shows that zinc ion produced by nano-ZnO and photocatalytic reaction make the fabrics have good antibacterial activity at low nano-ZnO content. When nano-ZnO concentration reaches 1.5 wt%, the antibacterial rate against Escherichia coli and Staphylococcus aureus reaches 98.52 % and 98.13 %, respectively.