Preparation And Performance Of Antibacterial Fibers Based On Nano Copper/Zinc Oxide Composites

Pathogenic microorganisms such as bacteria are widely distributed in nature that can cause diseases in animals,plants and humans through contact and adhesion.Harmful microorganisms have long been a threat to human health and social development.Textile fibers facilitate the attachment of microorganisms due to their porous shape and chemical structure.Meanwhile,various secretions such as sweat and sebum of the human body and environmental pollutants provide nutrients for microorganisms.Therefore,textile fibers are a good medium for microorganisms growth,reproduction and transmission.The existence of pathogenic microorganisms will not only reduce the performance of fibers,but also seriously endanger human health.Thus,imparting antibacterial properties to textile fibers is an effective way to protect their use value and reduce the risk of microbial infection.Effectively combining antibacterial materials with textile fibers through physical or chemical methods is the main method to prepare high-efficiency and durable antibacterial fibers.Currently,common antibacterial materials have disadvantages such as high price,high production cost and easy dissolution of metal ions to produce toxicity.Due to the widespread use of various antibacterial drugs,drug-resistant strains have emerged.Inorganic antibacterial materials have become a research hotspot due to their advantages of high stability,good heat resistance,low toxicity,and not easy to cause bacterial resistance.Among them,nano-zinc oxide（ZnO NPs）has abundant raw material sources,low price,good antibacterial activity and biocompatibility,which is a promising antibacterial material.However,since ZnO NPs generally need to be exposed to light to produce high antibacterial activity,and its use environment is limited.In addition,nano-copper（CuNPs）have gradually attracted the attention of researchers due to their excellent antibacterial properties.However,the high surface activity of nanoparticles makes them easy to agglomerate,and CuNPs are easily oxidized,which affects the normal performance of antibacterial activity and long-lasting antibacterial properties.Therefore,single-component antibacterial materials have certain limitations,the research and preparation of multi-component composite antibacterial materials has far-reaching significance.In this paper,nano copper-zinc oxide composite antibacterial agents（Cu-ZnO NPs）were prepared by in situ reduction method,and further introduced Cu-ZnO NPs into textile fibers by padding-high temperature baking method and centrifugation-electrospinning technology.The specific research contents are as follows:（1）CuNPs were loaded onto ZnO NPs by in situ reduction method to prepare Cu-ZnO NPs,effectively combining antibacterial agents with low melting point skin-core polyester（LMPET）fiber by rolling-high temperature baking method to prepare antibacterial fibers（Cu-ZnO@LMPET）.Field emission scanning electron microscopy（FESEM）,transmission electron microscopy（TEM）,fourier transform infrared spectroscopy（FTIR）,X-ray photoelectron spectroscopy（XPS）and other characterization methods were used to analyze Cu-ZnO NPs and Cu-ZnO@LMPET.The results showed that Cu-ZnO NPs and Cu-ZnO@LMPET were successfully prepared.The antibacterial properties of Cu-ZnO NPs and Cu-ZnO@LMPET were studied with Staphylococcus aureus（S.aureus）and Escherichia coli（E.coli）as target strains,the results displayed that both Cu-ZnO NPs and Cu-ZnO@LMPET exhibited excellent antibacterial activity,and after fiber was washed for 50 times,the antibacterial rates of E.coli and S.aureus were still over 97%and 98%,respectively,indicating that fiber had good washing resistance.The cytotoxicity test showed that Cu-ZnO@LMPET had good biocompatibility.The antibacterial mechanism of Cu-ZnO@LMPET was investigated by inductively coupled plasma mass spectrometer（ICP-MS）,zone of inhibition（ZOI）and electron paramagnetic resonance spectrometer（EPR）tests.The results showed that·O₂^-,¹O₂and·R were the main active species in the Cu-ZnO@LMPET antibacterial system,these active species could penetrate the bacterial cell membrane,destroy macromolecules such as proteins and nucleic acids in the bacterial cytoplasm,and then kill the target bacteria.（2）The study further used polyacrylonitrile（PAN）as substrates,which is more hydrophilic than LMPET,Cu-ZnO NPs were scattered on PAN by centrifugation-electrospinning technology to obtain antibacterial fibers（Cu-ZnO/PAN）.A series of characterization methods such as FESEM,TEM and FTIR were used to analyze Cu-ZnO/PAN.Similarly,S.aureus and E.coli were selected as target strains to evaluate the antibacterial properties of Cu-ZnO/PAN.The results displayd that Cu-ZnO/PAN had excellent antibacterial performances and good washing resistance.The antibacterial rates against E.coli and S.aureus that fiber was washed 50 times still reached 97%and above.Through water contact angle test,solid surface Zeta potential test and dye adsorption test,it was found that the hydrophilic performance of the fiber loaded with antibacterial agents was better,the Zeta potential was lower,and the bacteria were more easily fixed on the surface of fiber and fully contacted with the antibacterial agents.The antibacterial mechanism of Cu-ZnO/PAN was investigated by ICP-MS,ZOI and EPR tests.The research in this paper provides new ideas and methods for the development and preparation of textile fibers with excellent antibacterial performances.