Study On Electrospun Nano-air Filter Paper

The development of industrialization in China has led to the intensification of industrial pollution and the serious deterioration of environmental quality.The tiny particles in the air do harm to human body and its existing environment.It is very important to prepare effective filtering materials for reducing airborne particulate matter.As an important filter medium,air filter paper has been widely used in various fields.However,the traditional air filter paper has a single structure,large pore size,low filtration efficiency,and it is difficult to achieve a balance between low filtration resistance and high dust capacity.In order to solve this problem,nano-fibers with high specific surface area,large porosity and well fiber continuity were prepared by electrospinning technology,which were combined with air filter paper to construct nano-filter paper with multi pores and small pore diameter.In this paper,a new electrospun nano-air filter base paper(P-PVA)was prepared,and the effects of spinning solution concentration,spinning voltage,receiving distance and spinning time on its properties were investigated.Curing phenolic resin to prepare air filter paper and electrospun nano-filter paper(AP-PVA),and explored its paper characteristics.The optimal conditions for hydrophobic modification of polyvinyl alcohol(PVA)spinning solution were analyzed.Hydrophobic spinning solution(MPVA)and hydrophobic electrospun nano-filter paper(AP-MPVA)were prepared,and the hydrophobic properties and filtration characteristics of AP-MPVA were analyzed.The influence of multi-walled carbon nanotubes(MWCNTs)on the surface performance of electrospun nano-air filter base paper was explored,and the influence of calendering technology on the structure and filtration characteristics of the paper was analyzed.Firstly,the effects of PVA solution concentration,spinning voltage,receiving distance and spinning time on the properties of electrospinning nano-air filter base paper were investigated.Single factor experiment was conducted on the four factors:PVA solution concentration ranged from 0 wt%to 12 wt%,spinning voltage ranged from 15 KV-24 k V,receiving distance ranged from 12 cm-20 cm,spinning time ranged from 9 min-45 min.The results showed that when PVA solution concentration was 10 wt%,spinning voltage was 21k V,receiving distance was 15 cm and spinning time was 15 min,compared with air filter base paper,the mean pore size of electrospinning nano-air filter base paper decreased from14.35μm to 6.39μm,the filtering efficiency increased from 99.7822%to 99.9923%,and the initial resistance increased from 72 Pa to 83 Pa.Secondly,the method of enhancing the strength of electrospun nano-air filter base paper was explored.The electrospun nano-filter paper was prepared by curing it with phenolic resin to enhance its ability to resist the outside world.After curing,the gluing amount of phenolic resin was 20.21%.Compared with electrospun nano-air filter base paper,the longitudinal tensile index of electrospun nano-filter paper increased from 19.87N·m/g to 22.14 N·m/g,the burst index increased from 1.06 k Pa·m~2/g to 1.37 k Pa·m~2/g,and the mean pore size increased from 6.39μm reduced to 3.50μm.The filtration efficiency increased from 99.9923%to 99.9941%.The electrospun nano-filter paper met the requirements of both physical properties and filtration performance.The hydrophobic electrospun nano-filter paper was further prepared,and the optimal conditions of hydrophobic modification of PVA were explored.At the same time,the effect of hydrophobic MPVA on filtration characteristics was explored.SEM images after modification showed that the micro-morphology of MPVA nanofibers became rough under the influence of solvent.When the ratio of PVA solution to stearyl chloride was 25:3,the surface hydrophobic angle of hydrophobic electrospun nano-filter paper AP-MPVA(25:3)was 121.9°,and the hydrophobic stability was well.The air permeability was 247 L/m~2/s and the mean pore size was 4.87μm.The filtration efficiency was 99.9955%,the initial resistance was 90 Pa,and the dust capacity was 132 g/m~2.Finally,the experiment explored the method to improve the surface electrostatic phenomenon of electrospun nano-air filtration base paper,and explored the influence of calendering technology on the filtration performance.MWCNTs increased the electrostatic force of droplets in the electrostatic field,and weakened the bead phenomenon and electrostatic phenomenon on the surface of nanofibers;Calendering treatment had a significant effect on the pore size.The greater the pressure,the smaller the mean pore size.