Modification of a Poly(tetrafluoroethylene) Porous Membrane to Superhydrophilicity with Improved Durability

Abstract

The commercial fluorocarbon surfactant (FCS) DuPont Zonyl 321 fluorinated cationic surfactants, was employed to modify both flat-sheet and hollow-fiber poly(tetrafluoroethylene) (PTFE) porous membranes. The variation of morphology, wettability, and hydrophilicity durability to acid and alkali as well as the filtration performance of both membranes were investigated. Such superhydrophilic membranes showed better wetting stability and higher resistance to acid and alkali solutions. Moreover, both membranes exhibited good filtration performance.

Acid and Alkali‐Resistant Textile Triboelectric Nanogenerator as a Smart Protective Suit for Liquid Energy Harvesting and Self‐Powered Monitoring in High‐Risk Environments

“…First, it has a good acid and alkali resistance functionality compared with ordinary fabrics because of the intrinsic anti‐chemical performance of PTFE sheathed SETY. [ 16 ] As shown in Figure 1a‐i, the ordinary fabrics was corroded and damaged by sulfuric acid, but F‐TENG remained intact. Second, it can be used for self‐powered chemical leakage monitoring (Figure 1a‐ii), as obvious signals can be generated when the chemical droplet slapping on the core‐shell structured hydrophobic yarn.…”

Enhanced Wettability of a PTFE Porous Membrane for a High‐Temperature Stable Lithium‐Ion Battery Separator

“…3 indicated that the zeta potential of the pristine PTFE membrane was –8.41 mV. If coated with pure FCS, the zeta potential reversed to 1.05 mV due to the positively charged FCS 38. The zeta potential of the PTFE/FCS‐PEI separator further increased to 5.62 mV due to the coexistence of the positively charged FCS and the PEI.…”

“…PEI, which contains abundant polar amine groups, has been regarded as a valid candidate for imparting hydrophilicity and antifouling properties onto membrane surfaces during filtration [41,42]. Herein, PEI could be firmly deposited on the hydrophobic PTFE porous membrane with the help of FCS [38], generating a highly hydrophilic surface. It was interesting that, despite the decreased pore sizes and porosity (Figs.…”

“…However, the porous PTFE membrane often showed ultralow surface energy and high hydrophobicity, which led to difficult ion transportation, and thus it has seldom been used as LIB separator. Although numerous efforts were employed to improve the PTFE surface polarity and wettability, the focus was mainly on enhancing the separation or filtration processes for its use as separation membrane [36][37][38], rather than improving the ion diffusion and transportation for its use as LIB separator.…”

Cross-Linking Combined with Surfactant Bilayer Assembly Enhances the Hydrophilic and Antifouling Properties of PTFE Microfiltration Membranes

“…Polyethylene glycols are widely used in the hydrophilic modification of membranes and in constructing antifouling interfaces because of their excellent hydration capacity and anti-protein properties [28,29]. Polyethylene glycol laurate (PEGML) is a polyethylene glycol-derived nonionic surfactant that is widely used in industries because of its low price, low toxicity, volatility, and biodegradability [30]. At the same time, it can be deposited onto the PTFE membrane surface by hydrophobic interactions and van der Waals forces.…”