超快定向导湿与高效PM0.3滤除用聚乳酸纤维膜研究

Study on polylactic acid fibrous membrane for ultrafast directional moisture conduction and high efficiency PM0.3 filtration

  • 摘要: 空气污染已成为全球紧迫的环境问题,尤其是细颗粒物(PMs)对公众健康的危害,严重影响着呼吸系统和心血管系统的功能。随着空气污染程度的不断加剧,传统的空气过滤膜在保护作用上的局限性也逐渐显现,尤其是在长时间佩戴过滤面罩时,呼出的水蒸气以及汗液的积聚无法及时排出,导致膜表面湿度过高,进一步影响了过滤膜的舒适性与过滤效率。因此,开发具有高效低阻性能与优良定向导湿特性的过滤纤维膜,显得尤为关键。在此,我们通过电纺-电喷技术制备亲水层,首先将亲水性SiO2掺入聚乳酸(PLA)溶液中用于静电纺丝,同步采用电喷技术将高电活性CNT@ZIF-8纳米杂化体(碳纳米管表面原位生长ZIF-8)沉积于纤维表面得到SiO2@PLA-CZ NFM亲水层。随后,通过调控电纺参数,在亲水层上制备一层具有沟槽结构的PLA疏水纤维膜,形成“亲水-疏水”润湿梯度与“致密-疏松”孔径梯度的个人湿度管理聚乳酸纤维膜(PHM-PLA)。所得的PHM-PLA纤维膜具有出色的单向输水能力(传输指数为512.7%)和快速水分蒸发能力(72.4 g/m2/h),且PHM-PLA纤维膜表现出优异的透气性(183.7 mm/s)。此外,得益于多层结构以及电活性纳米颗粒的协同作用,PHM-PLA纤维膜在32 L/min流速下对PM0.3颗粒的过滤效率高达97.2%,同时保持了低压降(45.3 Pa)。总之,这种具有定向导湿以及高效低阻滤除PMs性能的PHM-PLA纤维膜为开发高舒适度防护装备提供了新途径。

     

    Abstract: Air pollution has become a pressing global environmental problem, especially the public health hazards of fine particulate matter (PMs), which seriously affects the function of the respiratory and cardiovascular systems. With the increasing level of air pollution, the limitations of traditional air filtration membranes in terms of their protective effects have gradually emerged, especially when wearing a filtration mask for a long period of time, the accumulation of exhaled water vapor and sweat cannot be discharged in a timely manner, resulting in high humidity on the membrane surface, which further affects the comfort and filtration efficiency of the filtration membrane. Therefore, the development of a filtration fibrous membrane with high efficiency and low resistance and excellent constant moisture conductivity is particularly critical. Here, we prepared the hydrophilic layer by the electrospinning-electrospraying technique, in which hydrophilic SiO2 was first doped into poly(lactic acid) (PLA) solution for electrostatic spinning, and a SiO2@PLA-CZ NFM hydrophilic layer was obtained by depositing highly electroactive CNT@ZIF-8 nanohybrids (ZIF-8 grown in situ on the surface of carbon nanotubes) on the fibrous surface using the electrospraying technique simultaneously. Subsequently, a PLA hydrophobic fibrous membrane with groove structure was prepared on the hydrophilic layer by regulating the electrospinning parameters, forming a personal humidity management PLA fibrous membrane (PHM-PLA FM) with “hydrophilic-hydrophobic” wetting gradient and “dense-loose” pore size gradient. The resulting PHM-PLA FM exhibit excellent unidirectional water transport (transport index of 512.7 %) and fast water evaporation (72.4 g/m2/h), and the PHM-PLA FMs show excellent air permeability (183.7 mm/s). In addition, thanks to the multilayer structure and the synergistic effect of electroactive nanoparticles, the PHM-PLA fibrous membrane achieved a filtration efficiency of 97.2 % for PM0.3 particles at a flow rate of 32 L/min, while maintaining a low pressure drop (45.3 Pa). In conclusion, this PHM-PLA fibrous membrane with constant moisture conductivity and high efficiency and low resistance to PMs filtration provides a new way to develop high comfort protective equipment.

     

/

返回文章
返回