| Due to the larger surface area and smaller diameter,the antimicrobial nanomaterial has expanded the application in water treatment and air purification.Electrospinning is an easy method to produce nanomaterials,which has the characteristics of maneuverability,convenience and low cost.This study aims to prepare the antibacterial nanomaterials based on electrospinning polyacrylonitrile.The N-halamine was added to the spinning solution in the way of physical blending.This paper mainly consists of three parts:First,electrospinning polyacrylonitrile(PAN)nanofibers were obtained by changing the spinning conditions such as concentration,distance from the needle tip to the collector and the spinning voltage.The structure and characteristics of spinning fiber were observed under different conditions,and the optimal spinning process was discussed.The results showed that the PAN spinning solutions at 8 wt%was regarded as the optimum concentration for the electrospinning nanofibers,the spinning voltage was 15 kV,and the spinning distance was 15cm.Under optimum condition,the surface of the nanofibers was smooth and uniform,with the diameter of about 350 nm.Second,PANnanofibershadantimicrobialpropertieswhen1-chloro-2,2,5,5-tetramethyl-4-imidazolidinone(MC)was added to the solution as a certain proportion to PAN.The optimal spinning process was also discussed to explore the optimum antimicrobial nanofibers.Antimicrobial properties was related to the chlorine content in PAN/MC nanofibers.Compared with results of different conditions,a suitable ratio was selected as the applicable content in nanofibers.Scanning electron microscopy(SEM)and Fourier transformed infrared spectroscopy(FT-IR)were employed to characterize the structure of nanofibers.Thermal gravimetric analysis was used to study the thermal properties of the antibacterial nanofibers.And water release performance and antibacterial properties of nanofibers were tested as well.The final results showed that when 5%MC(weight to 8%PAN)was put into the solution,the chlorine content of the antimicrobial nanofibers(PAN/MC nanofibers)was about 0.29%.The surface characteristics of nanofibers were analyzed by SEM and FT-IR.The storage stability,UVA light stability and water release stability of PAN/MC nanofibers were also tested.The antimicrobial efficacy of electrospinning nanofibers with MC against both S.aureus and E.coli O157:H7 was evaluated at different contact times.PAN/MC nanofibers could inactivate all S.aureus and E.coli O157:H7 within10 min.The antibacterial properties of the PAN/MC materials could inactivate S.aureus bioaerosols with more than 6 log reductions after 3 h exposure.Third,3-(4’-vinylbenzyl)-5,5-dimethylhydantion(VBDMH)was synthesized as a monomer,and Poly(VBDMH-co-MMA)were obtained by emulsion polymerization with monomer methyl methacrylate(MMA).By controlling the composition of monomers,the optimum synthesis process was selected combining with the analysis of SEM,~1H NMR,FT-IR and elemental analysis.The results showed the proportion of N in the synthesis of polymers was higher,when the initial mole ratio of VBDMH to MMA was 40 to 60,which indicates that N-halamine precursor in the polymer was higher,the proportion of the chlorine content was higher.In the following test,PAN/Poly(VBDMH-co-MMA)nanofibers would be prepared with copolymer under this ratio.Surface morphology,water release,and antibacterial properties of the PAN antibacterial nanofibers were investigated.The results showed that the addition of copolymers had no influence on the formation of the nanofibers.The nanofibers had good water release performance,and could kill all S.aureus and E.coli O157:H7 within 30 min. |
