Preparation Of Polyphenylene Sulfide Nanofiber Membranes By Electrospinning And Research On Separation Applications

With the increasingly serious environmental pollution,the phenomenon of corrosive substances such as strong acids,alkalis or chemical solvents in sewage is becoming more and more serious.At present,most of the substrates for separating sewage cannot withstand these harsh environments.As a high-performance thermoplastic resin,polyphenylene sulfide(PPS)has not only good stability,but also excellent acid and alkali resistance.Therefore,researchers tried to use it as a substrate for the separation of oil and water in harsh environments.However,the only method for the formation of PPS membrane is thermally induced phase separation.A large number of organic solvents has to be used as diluents,which is not conducive to environmental protection.Electrospinning is currently a common method for preparing membranes with high specific surface area and high porosity.In this paper,PPS nanofiber membranes were prepared by electrospinning for the first time.By studying the effects of different preparation conditions on the structure and performance of PPS-based nanofiber membranes,the functionalization and application of PPS-based fiber membranes were explored and studied:(1)The PPS/polyvinyl alcohol/polyacrylonitrile composite nanofiber membrane was prepared by the electrostatic spinning process,and then the polyvinyl alcohol component was removed by the sintering process to obtain the PPS composite nanofiber membrane.It was studied that the effects of the PPS/polyvinyl alcohol mass ratio and the highest calcination temperature on the membrane structure and performance,and a group of PPS composite nanofiber membranes with the best performance were selected for the separation experiment of surfactant-stabilized oil-water emulsions.The results showed that the maximum flux of the PPS composite nanofiber membrane to the three oil-water emulsions under gravity conditions is 1707 L/(m² h),and the separation efficiency is above 98%.At the same time,the PPS composite nanofiber membrane can maintain good performance in organic solutions stability.(2)On the basis of process(1),the same process was adopted to prepare PPS/titanium dioxide(TiO₂)composite fiber membrane.Through morphology observation,pore size,porosity and hydrophobicity tests,the influence of the addition of TiO₂ on the structure and performance of the fiber membrane was analyzed.The results showed that the pore size of the PPS-based composite fiber membrane increased from 0.73?m to 1.08?m,and the contact angle of water in the air increased from 145.0°to 150.2°after adding TiO₂ nanoparticles;in the oil-water separation experiment,the maximum flux of the PPS/TiO₂ composite fiber membrane to separate three water-in-oil mixtures is 3807L/(m² h),the separation accuracy is above 98%,and it has good cycle performance and anti-pollution performance under oil;in the photocatalytic degradation experiment,the PPS/TiO₂composite fiber membrane can degrade 75%of methylene blue dye,and showing good UV resistance.