Macro-preparation And Performance Study Of Solution Jet-spun PAN Micro-nanofibers

Solution blowing process is a new nanofiber spinning method which is derived from meltblowing.The process has shown great prospects with its widely raw material,safe operation,easy to mass production,et..Nowdays the researches of solution blowing are mainly focused on spinning process,fiber structure and performances.This study explored the rheology of solution,fiber modification and product application.Effect of solution' concentration and temperature for the solution rheological property,fiber forming and morphology was studied.The results showed that when the storage modulus and loss modulus are within a certain range,larger spinning solution concentration could improve the viscosity of the solution,which was conducive to the spinning of continuous fibers,without causing adhesion of needles,so around 16%is a suitable solution concentration;in order to speed up solvent's evaporation and maintain solution's viscosity with a smaller loss modulus to facilitate the draft of solution trickle,solution's temperature between 50?-65?is a suitable range for the solution blowing.The results of the effects of solution's concentration,high-speed airflow draft pressure and airflow's temperature indicated that the average diameter of nanofibers increased with the increase of the solution's concentration.When the draft pressure of the high-speed airflow was within a certain range,it was conducive to the draft of the nanofibers.However,when the solution's concentration exceeded a certain range,the mean diameter no longer decreased but increased.As the airflow's temperature increased,the average diameter of nanofibers increased,and as the temperature increased,the nanofibers curl and the degree of bending increased.Fluorine-modified acrylate(FA)was introduced into polyacrylonitrile(PAN)nanofibers using a blend spinning method.The influence of FA on solution's rheology,hydrophobicity of fiber mats and fiber forming was discussed,The results showed that fluorine was successfully introduced into the nanofiber mat because the addition of FA,which made the FA/PAN nanofiber mat obtained good hydrophobicity.The contact angle's average of FA/PAN nanofiber mat,the average diameter of nanofibers and the aperture of nanofiber mats all increased with the increase of FA's added content.The solution blowing nanofiber mats are suitable for filtration of particles above 0.6?m with high efficiency and low resistance;Compared to Thinsulate C40,the FA/PAN nanofiber mats had higher CLO values and better moisture permeability;it showed a good potential for the application of filtration,thermal protection and other fields.