TY - JOUR
T1 - Hierarchical Porous Poly(l-lactic acid) Nanofibrous Membrane for Ultrafine Particulate Aerosol Filtration
AU - Song, Jun
AU - Zhang, Bowen
AU - Lu, Zihan
AU - Xin, Zhiying
AU - Liu, Ting
AU - Wei, Wenyuan
AU - Zia, Qasim
AU - Pan, Kewen
AU - Gong, Hugh
AU - Bian, Liming
AU - Li, Yi
AU - Li, Jiashen
PY - 2019
Y1 - 2019
N2 - Ultrafine particulate aerosols less than 100 nm diffuse randomly in the air and are hazardous to the environment and human health. However, no technical standards or commercial products are available for filtering particle sizes under 100 nm yet. Here, we report the development of a porous poly(l-lactic acid) (PLLA) nanofibrous membrane filter with an ultra-high specific surface area via electrospinning and a post-treatment process. After PLLA fibres were electrospun and collected, they were treated by acetone to generate a blossoming porous structure throughout each individual fibre. Characterizations of morphology, crystallinity, and mechanical and thermal properties demonstrated that the porous structure can be attributed to the nonsolvent-induced spinodal phase separation during electrospinning and solvent-induced recrystallization during post treatment. The blossoming porous structure with high specific surface area contributed to excellent filtration efficiency (99.99%) for sodium chloride (NaCl) ultrafine aerosol particles (30–100 nm) with a low pressure drop (110–230 Pa). Notably, under 7.8 cm/s air flow rate, the membrane samples performed better for filtering smaller-sized aerosol particles than the larger ones when evaluated by the quality factor (0.07). Finally, this finding demonstrates that the electrospun membrane with a hierarchical pore structure and high specific surface area hold great potential in applications as air-filtering materials.
AB - Ultrafine particulate aerosols less than 100 nm diffuse randomly in the air and are hazardous to the environment and human health. However, no technical standards or commercial products are available for filtering particle sizes under 100 nm yet. Here, we report the development of a porous poly(l-lactic acid) (PLLA) nanofibrous membrane filter with an ultra-high specific surface area via electrospinning and a post-treatment process. After PLLA fibres were electrospun and collected, they were treated by acetone to generate a blossoming porous structure throughout each individual fibre. Characterizations of morphology, crystallinity, and mechanical and thermal properties demonstrated that the porous structure can be attributed to the nonsolvent-induced spinodal phase separation during electrospinning and solvent-induced recrystallization during post treatment. The blossoming porous structure with high specific surface area contributed to excellent filtration efficiency (99.99%) for sodium chloride (NaCl) ultrafine aerosol particles (30–100 nm) with a low pressure drop (110–230 Pa). Notably, under 7.8 cm/s air flow rate, the membrane samples performed better for filtering smaller-sized aerosol particles than the larger ones when evaluated by the quality factor (0.07). Finally, this finding demonstrates that the electrospun membrane with a hierarchical pore structure and high specific surface area hold great potential in applications as air-filtering materials.
KW - fibrous PLLA membrane
KW - hierarchical porous structure
KW - electrospinning
KW - ultrafine aerosol filtration
KW - solvent induced recrystallization
U2 - 10.1021/acsami.9b18083
DO - 10.1021/acsami.9b18083
M3 - Article
SN - 1944-8244
JO - ACS applied materials & interfaces
JF - ACS applied materials & interfaces
ER -