Study On The Technology And Device Of Slit Melt Differential Electrospinning

Electrostatic spinning is an effective method for preparing nanofibers,which is divided into solution electrostatic spinning and melt electrostatic spinning.As a branch of electrostatic spinning,melt electrospinning is green and pollution-free.It is an environment-friendly preparation method of nano-fiber.Traditional melt electrospinning is capillary with low spinning efficiency.Although there is an array needle to improve the spinning efficiency,this method will lead to the problem of needle plugging and so on.In order to realize the continuous,stable,green and batch preparation of nanofibers,no needle melt electrospinning process has been put forward.This is an effective process to realize the production of nanofibers.But at present,there is little research at home and abroad.The needleless melt electrospinning has great advantages in the green bulk preparation of nanofibers,but there are still the following shortcomings and problems to be solved:1.in the refinement of the fiber diameter,the characteristics of its green manufacturing and high strength are better used in the application,and this is the same as that of the solution electrospun fiber.The problems of melt electrospinning device and technology need to be solved.Through optimizing the spinning parameters and adding air assisted device,the diameter of fiber has been refined.2.in the supply and control of micro flow,the device of non needle melt spinning is more complex,the control of melt micro flow is difficult,and the design of melt flow channel and the demand of feeding mode are higher.Through the design of plasticizing system of single screw extruder,accurate control of flow and uniformity of spinning have been achieved.3.in improving the spinning efficiency,the influence factors of the jet spacing are studied from the experiment to the theory,the jet spacing is reduced,the number of jet roots is increased and the spinning efficiency is improved.Through the design of the runner and nozzle,and the combination of experiment and simulation,the jet spacing is 3.3mm,which greatly improves the spinning efficiency.According to the melt calculus idea proposed by Professor Yang Weimin,a slit melt differential electrostatic spinning device was designed independently,and the experiment platform was set up to test the equipment and the spinning experiment.The specific research contents are as follows:(1)independently design a slit melt differential electrospinning device.Based on the concept of melt differential,a slit melt differential electrostatic spinning device is proposed and designed.Its advantage is to produce multiple jets on a free surface,improve the spinning efficiency,and the auxiliary airflow can be used to refine the fiber.The design and experimental purpose of the device is to use the finger guide and realize the green mass production of nanofibers.(2)micro flow control and jet distribution in slit melt differential electrospinning device.The experimental platform was set up and the experiment of the device was carried out.The relationship between the rotating speed of the extruder and the spinning flow and the influence of the spinning flow on the uniformity of the flow material at the nozzle and the distribution of the jet in the spinning process were investigated.The precision control of the micro flow and the uniformity and stability of the jet in the spinning process were ensured.(3)research on fiber refinement of slit melt differential electrospinning.The influence of spinning voltage,spinning distance,spinning temperature and three spinning parameters on fiber diameter is found through orthogonal experiment,and the effect of single parameter on fiber diameter is explored,and the effect of air flow auxiliary device on fiber refinement is also explored.(4)research on jet spacing of slit melt differential electrospinning.The effects of spinning voltage,spinning distance,spinning temperature and sawtooth density on the jet spacing are investigated by experiments.The effect of electric field on the nozzle is simulated by COMSOL,and the influence factors of the jet spacing are explored and the rules are sought to guide and improve the spinning efficiency.To sum up,the research of a slit melt differential electrospinning process and device is proposed.It is expected to provide an effective method for green bulk preparation of nanofibers,which can be used in various fields for the wide application of nanofibers.