复合聚酰亚胺滤毡的制备及其滤除PM2.5颗粒

Preparation of Composite Polyimide Filtration Filter and Its Application in PM2.5 Removal

以260-350 g/m2的芳纶无纺毡为基底层、40-60 g/m2的耐高温无纺布为保护层,通过静电喷雾将高温粘合剂均匀涂布在基底层上,再采用静电纺丝技术将直径150-400 nm的可溶性聚酰亚胺（P84）纳米纤维均匀纺制其上,附上保护层,热压固化使3层材料紧密结合,得到三明治结构的耐高温纳米纤维复合过滤毡,用其去除模拟气溶胶（粒径0.3-10μm的Na Cl）颗粒.结果表明,复合滤毡粘结强度超过1000 k Pa,粘合剂对基底性能影响较小,少量纳米纤维可有效提高材料的过滤效率,对粒径2.0μm以上和1.0-2.0μm Na Cl颗粒的过滤效率分别达100%和99.5%以上.

A composite felt with sandwiched structure was prepared by evenly depositing basis of 150-400 nm electrospun soluble polyimide （P84） nanofibers on substrates of aramid nonwoven fabrics of 260-350 g/m^2. The substrates were pre-sprayed electrostatically with high-temperature adhesives to bind the nanofibers. Another protective layer made of high-temperature nonwovens with basis of 40-60 g/m^2 was used to shield the nanofibers. The composite was then hot-pressed to gain the binding strength as the adhesives solidified, to remove the simulated dusts, 0.3-10 μm NaCl aerosols. The results showed that the property of the substrate was less affected by the adhesive, and the composite had a strength higher than 1000 kPa. Even a small amount of P84 nanofibers can obviously enhanced the filtration efficiency. The filtration efficiency of the composite reached to 100% to the particles equal and greater than 2.0 μm, 99.5% to the particles 1.0-2.0 μm in diameter.