Study On The Single-step Surface Coating Of Inorganic Nanoparticles On The Electrospun Nanofibers In Situ And Its Application

The preparation of the electrospinning nanofibers membranes is more and more convenient,and also has the advantage of high specific surface area.But its.functionalization always have many difficulties to overcome,especially when it refers to the single step preparation of functional nanofibers membranes.This thesis adopts several different electrospinning technology,including single spinning,coaxial electrospinning and side-by-side electrospinning.Without hurting its base material into fine structure,the preparation of different function components by el'ectrospinning can be studied in its application.The base material used hydroxypropyl methyl cellulose(HPMCX polyacrylonitrile(PAN)and poly(vinylidene fluoride)(PVDF)in turnO and fiber forming effect is good.Adhesive adopted alpha cyano glue agent ethyl acrylate(trade name is 502 glue)and epoxy resin(EP)respectively,and bond coating is obvious,Functional components including ferulic acid(FA)drugs,the synthesis of anatase(TiO2)and substrate itself.The electrospinning of blend compon'ents or more fluid electrospinning can nano-bind functional components by one-step are good methods to load functional components on the nano.fiber membrane.The preparation of nanofibers membrane can applied in different fields under maintaining its nanofiber membrane integrity.Nanofibers membr,ane preparation research content mainly includes the following four aspects:(1)Electrospun medicated HPMC-based HCs were prepared through a modified coaxial process.Different from the traditional applications of HPMC in providing drug-controlled release profiles,the HCs could provide immediate drug release of FA due to the synergistic actions of HC structural factors(small diameters,high porosity,and web structure)and the reasonable selections of pharmaceutical excipients to form good solid cocktails for the encapsulated drug,For the first time,the sizes of the compound Taylor cone and straight fluid jets under different working conditions were quantitatively measured.The results showed that the flow rate of the sheath solvent exerted a significant influence on the spinning processes and the quality of the generated HCs.The diameter of the composite linear nanofibers could be manipulated within a suitable range of sheath fluid flow rates.The fiber-based HCs were amorphous composite materials.The smaller the fiber diameter was,the better the hydrophilicity of the HCs was.In vitro dissolution tests demonstrated that the electrospun HCs exhibited a much better functional performance than the casting HCs in providing immediate drug release.(2)The super-hydrophobic PVDF/EP core-sheath structure nanofibers was prepared by coaxial electrospinning,it can coat on the metal substrate by one-step in order to achieve anticorrosive effect.The sheath fluid is EP,can form nano-binding between PVDF and metal substrate and with each other.SEM results show that the core-sheath structure nanofibers membrane has been successfully prepared,with the increase of the content of EP,linear form of the fibers is changed tinily.TEM,FTIR and EDS analysis further shows that the existence of EP sheath.nanofibers membrane coating of different core-sheath rate ratio have close contact angle(CA).It may be due to sheath liquid content of the EP is less,so the fiber PVDF membrane contact angle is close to the single spinning nanofiber membranes.Shot and magnify cross fiber membrane surface after the scratches,can prove that because the existence of the binder and the combination of the matrix is getting better and better.And through the EIS electrochemical impedance test,it shows that the preparation of metal surface coating can protect the metal matrix and exist in harsh environments,such as alkali stability.Finally we hope that the preparation of PVDF/EP core-sheath nanofiber membrane coating can provide hydrophobic organic coating with some new ideas and ways.(3)In order to achieve the function of TiO2/502 liquid daub of PAN nanofibers membrane preparation,and apply the fiber membrane for methylene blue pollution water treatment research.Firstly,successful anatase nano sol preparation by the sol-gel synthesis method,it can be mixed evenly with EP when making confecting blended spinning solution.When Sheath-core rate flow is 0.25 under the condition of application of the modified coaxial electrospinning process,preparation of TiO2/502 functional liquid onto PAN nanofibers diameter size is uniform,and uniform distribution of fiber,adhesion between fiber and fiber form appropriate block adhesion blocking pores,fiber diameter and its distribution is an average of 320±90 nm.The preparation of TiO2/502 daub PAN nanofibers get good mechanical properties,and the fiber membrane has good wettability at the same time.And we detect the dye methylene blue in the blue of ultraviolet-visible spectrophotometer to establish its quantitative detection method.Standard linear equations of methylene blue is:A=0,14433+0.07423 C(correlation coefficient R?0.9991),linear range is:1 to 20?g/mL,TiO2/502 daub PAN nanofibers have good photocatalytic degradation performance.Under the condition of natural light placed after 1 hour,0.2 g(15.88 mg)nanometer titanium dioxide degradation can be 98,73%20 mL concentration for 20 mu g/mL methylene blue solution,the degradation ability of 24.87 mu g/mgTiO2,beyond the 7.73 mu of g/mgTiO2 titanium dioxide powder itself.(4)Janus nanofibers film on the cotton fabrics in plain were fabricated successfully by side-by-side electrospinning with eccentric needle,one fluid is PVDF,the other is about blend EP and TiO2 even fluid.The continuous fine fibers from theeccentric nozzle can be prepared,because of the two strands of fluid nozzle surface electrostatic repulsion and enlarged the contact area.TiO2 is through laoratory prepared.hydrophilic and ultraviolet shielding effect respectively with the contact Angle tester and ultraviolet-visible spectrophotometer instrument(UV-Vis)characterization,The results show that the anatase was successful synthesis and form uniform dope;the Janus nanometer fiber membrane contained TiO2 was successful prepared.Along with the increase of the content of EP,Janus nanom eter fib er surface of the linear form don' t have he much effected.Some Janus nanofiber membrane contact angle can achieve 140",further shows the caking agent EP improve the fiber membrane integrity.Finally it showed that super-hydrophobic Janus nanofiber membrane contained TiO2 particles on the fabric has good ultraviolet shielding effect.