Research On The Mechanical Properties Of Electrospinning PPESK Micro/Nano Fibers And Membranes

Micro/nano fiber membranes made by electrospinning have very large surface area to volume ratio,high porosity and good mechanical properties which are widely used in biomedicine,complex filter protection,enhancement and electronic sensors and other fields.However,the mechanical properties of electrospinning fiber membranes are not that good,which become the key factors to limit its application in practical production.Testing results show that the mechanical properties of single fibers are better than that of fiber membranes.Therefore,it is important to explore the mechanical relationship between a single fiber and a fiber membrane.The mechanical properties of PPESK micro/nano fibers and fiber membranes,which were made by electrospinning,were tested at room temperature.To explore the factors influencing the mechanical properties of fiber membranes and to improve the mechanical properties,a mathematical relationship was made between a single fiber and a fiber membrane.From this research,we found that:1)With a plate collector,randomly oriented micro/nano fiber membrane can be get.It can be found from the SEM of electrospinning PPESK micro/nano fiber membranes that the diameter of the fiber near to Gaussian distribution.And from the statistics of fiber orientation,it can be found that fibers are arranged in all directions with similar probability.Thus,we can consider it that using a plate collector we can get randomly oriented in all directions micro/nano fiber membrane.2)The geometry size of the samples will have influence on the mechanical properties of fiber membrane.The mechanical properties of electrospinning PPESK micro/nano fiber membrane made by using a plate collector are tested by adopting different aspect ratio samples.It can be found from the results that with the increase of aspect ratio the elastic modulus,tensile strength and yield strength are increased.On the contrary,elongation at break decreases sharply.3)The tensile strength of a single electrospinning PPESK micro/nano fiber is related to the diameter of the fiber.Based on the single fiber mechanical properties,it shows that the tensile strength of the fiber increases with a smaller diameter.Based on numerical fitting of the fiber tensile strength,a mathematical relationship can be established between fiber diameter and tensile strength: σ = 266.46..4)The properties of electrospinning PPESK micro/nano fiber membrane can be influenced by many factors.It can be found from the mathematical model that factors affecting the mechanical behavior of fiber membrane including: geometry size of sample,fiber orientation,porosity and tensile strength of a single fiber.When calculating the tensile strength of the fiber membrane,the porosity need to be taken into account.Maintaining the geometrical dimensions and porosity of the fiber membrane and the tensile strength of the single fiber,the mechanical properties of the whole fiber membrane can be improved by increasing the orientation of the fiber.5)With the high-speed roller as a collector,it was found that the spinning voltage,injection speed and receiving distance have an influence on the orientation of the fibers and the mechanical properties of the fiber membranes when the solution concentration is constant.Through the statistical analysis of the fiber membrane diameter and the angle of the axial,the distribution of the fiber membrane is similar to the Gaussian distribution.Through the orthogonal test,it is found that the effect of the angle standard deviation of the fiber membrane is: injection speed <spinning voltage <receiving distance;the effect of the mechanical properties of the fiber membrane including the porosity is: spinning voltage <injection speed <receiving distance.The orthogonal test shows that the optimum mechanical conditions are as follows: the spinning voltage is 12 kV,the injection speed is 0.20 mm / min and the receiving distance is 12 cm.In this process conditions,the standard deviation of the angle can reach a minimum of 5.46 °,and the maximum tensile strength can reach 72.38 MPa.