Preparation and Characterization of Poly(Lactic Acid)/Poly (ethylene glycol)-Poly(propyl glycol)-Poly(ethylene glycol) Blended Nanofiber Membranes for Fog Collection

Abstract

Fog is a resource with great potential to capture fresh water from the atmosphere, regardless of the geographical and hydrological conditions. Micro-sized fog collection requires materials with hydrophilic/phobic patterns. In this study, we prepared hydrophilic poly(lactic acid) (PLA)/poly(ethylene glycol)-poly(propyl glycol)-poly(ethylene glycol) (PEG-PPG-PEG) blended nanofiber membranes with various PEG-PPG-PEG concentrations by electrospinning. Changes in the morphological and chemical properties, surface wettability, and thermal stability of the PLA/PEG-PPG-PEG composite nanofiber membranes were confirmed using field-emission scanning electron microscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, contact angle testing, and thermogravimetric analysis. As the PEG-PPG-PEG content of the nanofiber membranes increased, their hydrophilicity increased. Water stability, membrane porosity, and water transport rate tests were also conducted to observe the behavior of the hydrophilic PLA nanocomposite membranes in aqueous media. Finally, we applied the PLA-based membranes as fog collectors. As the PEG-PPG-PEG content of the nanofiber membranes increased, their ability to collect fog increased by over 40% compared with that collected by a pure PLA membrane. The prepared membranes not only improve the ability of fog collectors to harvest water but also broaden the use of PLA-based membranes in multiple applications, including tissue engineering, drug delivery, scaffolds, and pharmaceuticals.

Fabrication and Characterization of Electrospun Chitosan/Polylactic Acid (CH/PLA) Nanofiber Scaffolds for Biomedical Application

“…To address the hydrophobic nature and low biocompatibility of PLA blends, PEG was utilized. Toncheva et al revealed that PEG incorporation by physical blending or chemical grafting did not significantly modify the surface wettability of the PLA electrospun mats [ 50 ]. Otherwise, further research established proved that blending PEG into a PLA solution is a successful strategy to increase the hydrophilicity of PLA electrospun membranes.…”

Preparation and Characterization of Electrospun Poly(lactic acid)/Poly(ethylene glycol)–b–poly(propylene glycol)–b–poly(ethylene glycol)/Silicon Dioxide Nanofibrous Adsorbents for Selective Copper (II) Ions Removal from Wastewater

“…The PLA and PEG-PPG-PEG solutions were initially prepared separately. First, 12.5% ( w / v ) of PLA powder was dissolved in DCM at 50 °C for 1 h, and then 9% ( w / v ) of PEG-PPG-PEG powder was dissolved in DMF at 50 °C for 30 min [ 17 ]. After preparing each solution, both the solutions were blended in the 4:1 ratio for PLA and PEG-PPG-PEG solutions, respectively, and kept for 12 h of stirring to prepare an absolutely homogenized solution.…”

“…On a super hydrophilic surface, water tends to form a thin film rather than droplets [ 16 ], which helps the adsorbent to capture the maximum amount of pollutants on its surface. PLA’s surface is highly hydrophobic, although many surface and bulk changes have been found to improve hydrophilicity; thus, coating, grafting, and blending PLA with more hydrophilic polymers is used to modify the surfaces of PLA [ 17 ]. An important factor needs to be taken into account when using biopolymer as an adsorber.…”

Overview of the design of bionic fine hierarchical structures for fog collection

“…To date, most researchers only focused on the directional transportation of water on fibers. 113 However, in the five years, some groups focused on the reversibly directional movement of tiny droplets. Liu et al designed a type of spindle-knot with HS via the double dip-coating technique in 2017.…”