Research On The Control Mechanism Of Multi-needle Electrospinning Technology

With the rapid development of nano-technology,nanofiber technology has become the forefront and focus of researching of fiber science.And it has been applied to the fields of textile,electronics,machinery,biomedicine,chemical industry,etc.Electrospinning technology is the simplest and most efficient way to prepare nanofibers.The nanofiber produced by this way has many advantages.As a result,electrospinning technology has promising development prospect.Due to the introduction of high voltage electric field the viscosity and surface tension of polymer solution are changed resulting in the unstable spiral motion of polymer solution jet under the mixedeffects of electric field,force field and flow field.Furthermore,the jets in unstable whipping motion arouse to twine together due to the strong mutual interference of the electric fields between needles,which seriously influences the uniformity and quality of nanofiber deposition.In this paper,we changed the multi-needle arrangement to improve uniformity of electric field at needle points.In this way,the unsteady whipping of the jets is suppressed,which improved the quality of nanofiber.The research mainly includes three parts:first,establishing the multi-needle electrospinning model by using COMSOL Multiphysics 5 and conducting finite element analysis of the electric field.And then bring up a needle distribution model to solve the problem of uneven distribution of electric field.By setting up a model of 5 needles.This paper aiming at optimizing the electric field by arranging the needles in the shape of a geometric linear convex which is to achieve the result of uniform electric field distribution of the needle head.And then,build a multi-needles electrospinning device and adjust test parameters of the device by using Panasonic PLC(FP-XH C60T).The parameters include:syringe feed speed adjustable electric spinning device and horizontal reciprocating movement speed adjustable.With the help of HuiChuan Touch-screen IT5070T,the researcher visualized and adjusted the test parameters.Finally,on the basis of the theoretical analysis the actual work results of multi-needles electrospinning device in convex arc-shaped arranged is verified.Through modeling and simulation multi-needles arrangement in a linear convex arc-shaped reduces the field intensity of edge needle points and improves the uniformity of electric field distribution at the needle points.The specially established electrospinning device is tested and debugged and the system can act the expected function and work stably.With the application of linear convex arc-shaped arrangement to 5 needles model and PEO as experimental materials the experiment is fulfilled.The experimental results show that with the new arrangement the unstable whipping phenomenon of the polymer jet has been obviously suppressed and the uniformity of deposited the nanofiber on the collector has been improved.