Preparation And Structural Properties Of Cu₂O/PA6 Antimicrobial Composite Fiber

Nylon 6（PA6）fiber are the most widely used polyamide fiber,with the advantages of low cost,good elasticity and high impact resistance,and are mainly used in clothing fabrics,home textiles and industrial fabrics.The fiber itself is a high surface area material,plus contact with the human body will be attached to grease and dander and other substances,is extremely conducive to the attachment and growth of harmful micro-organisms,conventional PA6 fiber also do not have the ability to kill germs.As people become more aware of harmful microorganisms such as bacteria and viruses and improve their quality of life,there is an urgent need for fiber products with antibacterial and antiviral capabilities.The antimicrobial properties of PA6 fibers are mainly derived from the antimicrobial agents added to the matrix.With the advancement of research and development and the development of nanomaterials,inorganic antimicrobial agents are gaining importance due to their efficient and broad-spectrum antimicrobial ability and excellent thermal stability.Cu₂O antimicrobial agent has excellent antimicrobial properties,but also has the advantages of low cost raw materials,easy production steps,safe and green,is a natural and suitable for industrial production of excellent antimicrobial agent.There are many studies on the preparation of Cu₂O,but most of them are still in the laboratory trial stage.It is essential to develop ways of preparing Cu₂O that are suitable for large-scale production and low cost.In this paper,Cu₂O antimicrobial agent is prepared by a safe and green glucose reduction method.Cu₂O was successfully prepared by varying the reaction temperature and concentration and characterised using XRD and SEM.The purity of the Cu₂O prepared under different conditions is high and almost free of impurities.The Cu₂O prepared is spherical or sphere-like in shape,and the particle size distribution of the Cu₂O prepared at different temperatures is different,with the particle size decreasing and then increasing as the temperature increased.An increase in concentration also increase the particle size of Cu₂O.The antibacterial properties of Cu₂O are characterised using the minimum inhibitory concentration method at Cu₂O concentrations of The antibacterial performance of Cu₂O is characterized by the minimum inhibition concentration method,and E.coli and S.aureus are completely killed at Cu₂O concentrations of 0.25 mg/m L and 0.125 mg/m L,respectively.The surface modification of Cu₂O is carried out using silane coupling agent KH-550,and the optimal modification scheme is explored by changing the amount of KH-550.After modification,both N and Si elements appeare on the surface of Cu₂O.The water contact angle and zeta potential indicated that the optimum addition of KH-550 is 1.5%.The Cu₂O/PA6 composite is then obtain by blending the modified Cu₂O with PA6 to investigate the effect of modified Cu₂O on the material properties.The addition of modified Cu₂O reduce the crystallinity of PA6 and increase the crystallization rate.SEM showe that the dispersion of modified Cu₂O in PA6 became better and agglomeration is less likely to occur.PA6 masterbatches with different Cu₂O contents are prepared by melt blending,and rheological experiments are carried out by capillary rheometer and rotational rheometer to investigate the effects of Cu₂O addition,temperature and shear rate on the viscosity of the antibacterial composite masterbatch blending system.The results show that the viscosity of the system deteriorated with the increase of Cu₂O addition,and the overall performance is optimal at 20%Cu₂O addition.The PA6 masterbatch with different Cu₂O particle sizes was also blended to investigate the effect of Cu₂O particle size on the spinnability of PA6.The results show that the spinnability of Cu₂O with particle sizes ranging from 800 to 1200 nm is better,while Cu₂O with particle sizes of 1500 nm and1800 nm meet the spinning requirements,but the spinnability is poor.Cu₂O/PA6 antibacterial composite fiber are prepared by masterbatch melt spinning,and the physical and chemical properties and antibacterial properties of the fiber are investigated.The addition of Cu₂O cause a slight decrease in the mechanical properties of PA6 fibers,and the mechanical properties are poor after the Cu₂O content reached 2wt%.The addition of Cu₂O makes the crystallinity of PA6 decrease,the crystallization rate increases,the crystal type gradually changes fromαcrystal type toγcrystal type,the phenomenon of molten bimodal peak appears,and the thermal stability decreases.After20 washes,the antimicrobial properties of the fiber decrease to a certain extent,but they still have good antimicrobial and washing resistance.