PP/PMIA@PVDF-HFP纳米纤维复合滤材的制备及性能

Preparation and Performance of PP/PMIA@PVDF-HFP Composite Air Filter Material

随着空气污染的日益严重,高效低阻空气过滤材料的开发成为研究热点.为了提高聚丙烯(PP)熔喷过滤材料的过滤性能,本文以PP熔喷过滤材料为基材,聚偏氟乙烯-六氟丙烯(PVDF-HFP)为皮层,聚间苯二甲酰间苯二胺(PMIA)为芯层,采用同轴静电纺丝技术制备了具有高效低阻特性的PP/PMIA@PVDF-HFP纳米纤维复合滤材,研究了纺丝工艺和热处理等对滤材形貌、孔径、透气性和过滤性能的影响.在高温作用下,耐高温性能优异的芯层组分PMIA可以保持原有形态,而低熔点的皮层组分PVDF-HFP将会熔融,进而将纳米纤维粘结在一起.因此,通过热处理的方式可以实现纳米纤维膜孔结构的调控,并提高复合纤维滤材对空气中微小颗粒物的拦截能力.结果表明,当静电纺丝时间为60min时,热处理后PP/PMIA@PVDF-HFP纳米纤维复合滤材孔隙率稳定在约75%,平均孔径为2.58μm,透气率为132.74mm/s;对粒径<2.5μm的固体颗粒物(PM2.5)的过滤效率可达97.67%,过滤阻力仅为45.1Pa,综合性能较优,且在不同风速、不同颗粒物浓度和长时间使用等条件下仍能保持优异的过滤性能.

Air pollution caused by particulate matter(PM)is a significant threat to human health,making the development of air filtration materials with high efficiency and low resistance a research priority.In order to improve the filtration performance of polypropylene(PP)melt-blown filter material,a micro/nanofiber composite air filter material was prepared using coaxial electrospinning technology.During the electrospinning process,the spinning solution of poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP)was used as the skin layer,while the spinning solution of poly(m-phenylene isophthalamide)(PMIA)was used as the core layer,and the PP melt-blown material was used as the substrate.The effects of spinning process and post-treatment on the morphology,pore size,air permeability,and filtration performance of the filter material were studied.During the post-treatment process,the skin layer(PVDF-HFP)will melt and attach to the surface of PMIA nanofibers,which reduced the pores between the fibers,resulting in efficient removal of particle matters in the air.The results show that when the electrospinning time is 60 min,the average pore size of the PP/PMIA@PVDF-HFP composite air filter material is 2.58μm with an air permeability of 132.74 mm/s.The filtration efficiency of PM2.5 can reach 97.67%,with a filtration resistance of only 45.1 Pa.Moreover,the composite filter material exhibited excellent filtration performance under different wind speeds,particle concentrations,and long-term use.In conclusion,the filtration performance of PP melt-blown filter material was improved via the introducing of PMIA@PVDF-HFP nanofiber membrane.The findings of this study provide important information for future research in this field.