Study On Preparation And Performance Of Electrospun Polymer Fiber Composites

Electrospinning is an important micro/nanofiber processing technology.By adjusting the process conditions and the composition of polymer solutions,micro/nanofibers with controllable porosity and special microtopography can be designed.Fibers prepared by electrospinning technology have the advantages of high specific surface area,high porosity,easy size control,and easy functionalization.In this paper,three typical organic conjugated molecular materials DR1,MWCNT and P3HT were selected as the research objects,and two polymer fiber composite materials were prepared by electrospinning method.Using the polarization effect of the high-voltage electric field during the electrospinning process,the precise control of the hydrophilic and hydrophobic properties of the surface was achieved,and the electric field polarization control conjugated polymer film device was built,and the molecular orientation of the conjugated molecules in the fiber spinning process was revealed,and mechanism.The main works are as follows:1.The PAN/DR1 composite fiber film was prepared by electrospinning technology,and the orientation of the organic conjugated small molecule DR1 in the high voltage electric field was studied.First,the electrospinning process parameters were determined by SEM morphology characterization,and a high quality PAN/DR1 composite fiber film was prepared.Through a series of tests such as FTIR,XRD,TGA and water contact angle,it was found that the incorporation of DR1 molecules improved the PAN the temperature at which oxidation and cyclization begin to occur.The water contact angle of the composite fiber membranes prepared under different voltage intensities increased from 81.4°to 118.6°,it can be seen that under the action of the high-voltage DC electric field,the DR1 molecules will be rearranged,and the functional groups in the molecular structure will be deflected,-NO₂ is more arranged towards the outer surface of the composite fiber membrane,while-OH is arranged towards the inner surface of the composite fiber membrane,and with the increase of the electric field strength,the arrangement degree of DR1 further increases.The preparation of smart fiber film is realized.2.The PAN/MWCNT composite fiber film was prepared by electrospinning technology,and the orientation of the tubular organic conjugated molecule CNTs in the high voltage electric field was studied.The parameters of the electrospinning process were determined by SEM morphological characterization,and high quality PAN/MWCNT composite fibre films were prepared.FTIR,XRD,TGA and tensile tests were used to find that the structure of PAN molecules was maintained in the composite fibrous films after doping with MWCNT,and no new chemical bonds were formed between the addition of MWCNT and PAN molecules.Under the action of high voltage DC electric field,the MWCNT will be polarized and the polarization rate is extremely strong.The polarized MWCNT are oriented along the electric field direction,which improves the degree of crystallization of PAN and the fracture strength of the fibrous membrane,it lays the foundation for the application of PAN composite fiber membrane.3.In order to explore the orientation process and mechanism of conjugated molecules during electrospinning,the orientation of organic conjugated polymer P3HT under the action of DC electric field was studied by electric field induction technology.The effects of electric field treatment time,electric field strength and whisker aggregate size on the assembly process in the P3HT whisker aggregate solution were estimated,and the mechanism of electric field induced assembly of P3HT whisker aggregates was explored in depth.Under the influence of the electric field,the dipoles of P3HT are induced to align along the direction of the electric field,causing the charged whiskers to undergo dielectrophoresis and assemble into fibers in a head-to-tail manner.The assembled fibers are oriented along the?-?stacking direction,and the electric field-induced assembled P3HT fiber film has anisotropy,which lays the foundation for the application of electrospinning composites.