Research On The Structure Control Of Transparent Nanofiber Membrane And Its Air Filtration Performance

Air pollution affects people's living quality tremendously,and it poses a serious health threat to the public.Considering the fact that most people spend the majority of their time indoors,protecting indoor air environment can be an effective measure in reducing the associated health risks.Note that outdoor PM2.5 can enter indoor environments through ventilation and infiltration processes,windows have become an issue for people to study.Coating window screen with nanofibers is a effective way to prevent outdoor PM2.5 from entering indoor environments for their good filtration performance.This work aim to improve the filtration performance,light transmission performance and mechanical properties of nanofibrous membranes.The main contents are as follows:In order to solve the problem of low product efficiency of nanofibers,PAN nanofiber membranes are prepared by electrostatic induction-assisted solution blowing in this work.And the in-situ formation of 1,3,2,4-dibenzylidene-D-sorbitol(DBS)nanowires is used to improve the crystallinity of the nanofibers and improve the mechanical properties of the nanofibers.When the concentration of DBS nanowires is 7 wt%,the mechanical properties is 1.47 times better than pure PAN nanofibers.In addition,the addition of DBS changes the surface morphology of the fiber,improves the bulkiness of the fiber membrane,and improves the filtration effect and gas permeability of the fiber membrane.When the light transmittance of the material is?75%,the filtering effect of the material on PM2.5 is about 100%,and the filtration resistance is 60 MPa.PMMA is selected as a matrix of the nanofiber to improve the light transmission property of the nanofiber membrane.And the composite polylactide stereocomplex(sc-PLA)is used as a mechanical reinforcement material to study the effect of different amounts of sc-PLA on the nanofiber properties.As a result,it is found that the fiber membrane formed a composite structure of coarse/fine fiber due to the addition of sc-PLA,which is beneficial to improve the mechanical properties and filtration properties of the materials simultaneously.When the sc-PLA content is 5 wt%,the breaking strength of the nanofiber membrane is increased by 140%.When the fiber membrane transmittance is?83%,the filtration efficiency is 99.5%for PM2.5.In order to improve the light transmittance and mechanical properties of nanofiber membranes,the amorphous Poly(ethylene terephthalateco-1,4-cylclohexylenedimethylene terephthalate)(PETG)is used to prepare nanofibers by electrospinning.And employ the effect of nanofiber diameter and nanofiber film thickness on the light transmittance of the nanofiber membrane.The result shows that,when the light transmission performance is?83%,the filtration efficiency of the PETG nanofiber membrane to PM2.5 reached 99.9%.