Porous Polytetrafluoroethylene Research Articles

Construction of rough and porous surface of hydrophobic PTFE powder-embedded PVDF hollow fiber composite membrane for accelerated water mass transfer of membrane distillation

The construction of rough and porous hydrophobic membrane surface is expected to overcome the obstacles including low permeate water flux and membrane pore wetting which greatly restrict the development of membrane distillation (MD) technology. In this study, a rough and porous polytetrafluoroethylene (PTFE) powder-embedded polyvinylidene fluoride (PVDF) hydrophobic coating layer was compounded on the outer surface of PVDF hollow fiber support membrane by the dilute solution coating-phase inversion method. PVDF hollow fiber support membrane was fabricated by the dry-jet wet-spinning technique. PTFE powder was directly incorporated in PVDF dilute coating solution and embedded in the porous PVDF coating layer after the nonsolvent induced phase separation (NIPS). The variations of membrane morphology, surface chemical compositions, hydrophobicity and wetting resistance were investigated by scanning electron microscope (SEM), Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), dynamic water contact angle (WCA) and liquid entry pressure (LEP) analysis. Membrane separation performance including desalination and ionic dyes removal properties was evaluated by VMD experiment. Compared with PVDF hollow fiber support membrane, both the surface hydrophobicity and the water permeability of the PTFE powder-embedded PVDF hollow fiber composite membrane (HFC) had obvious improvement. The surface WCA and permeate water flux increased from 92.6° and 11.3 kg/m2.h for PVDF support membrane to 133.6° and 26.8 kg/m2.h for the PTFE powder-embedded HFC membrane meanwhile NaCl rejection can be maintained above 99.9% (3.5 wt% NaCl aqueous solution at 50 °C and permeate pressure at 31.3 kPa). The separation performance of HFC membrane can remain stable without obvious pore wetting during the continuous MD operation for 36 h. Different from the desalination, porous hollow fiber membrane would adsorb two different charged dyes, Congo red (CR) and methylene blue (MB) to a certain extent, resulting in the decrease of membrane flux and the change of permeate water quality. Finally, the MD separation mechanism of inorganic salt, anionic dye and cationic dye by PTFE powder-embedded HFC membrane was proposed.

Tailoring micro/nanostructured porous polytetrafluoroethylene surfaces for dual-reversible transition of wettability and transmittance

Materials with dynamic transition are current mostly limited to two-state transition of single property. Herein, a textured polytetrafluoroethylene (PTFE) film with hierarchical porous micro/nanostructures is fabricated by one-step femtosecond laser line-by-line scanning technology. The as-prepared sample is superhydrophobic and opaque, and its wettability and optical transmittance can be simultaneously controlled. As the sample prewetted with alcohol, it displayed superhydrophilicity with high transparency. In contrast, since the prewetted surface was dried, it recovered its original superhydrophobicity and opacity. The switching repeatability, applicability of solutions, stability of the samples are also demonstrated. By using its controllable switching performances, potential applications such light pass/block controlling, anti-fogging, cooling were realized on the as-prepared surfaces. This work reports a smart surface with dual-functional transition ability, which could open fresh ideas for a broad range of multifunctional applications.

Preparation of porous PTFE/C composite foam and its application in gravity‐driven oil–water separation

AbstractPorous superhydrophobic filtration media with durable performance that can be used in harsh environments remain an urgent requirement. Here, we designed and prepared a porous polytetrafluoroethylene (PTFE)/C composite foam derived from PTFE/glutaraldehyde‐crosslinked poly(vinyl formal) foam via a method of low‐temperature in situ carbonization by the combination of sintering in nitrogen atmosphere and oxygen atmosphere. The as‐prepared porous PTFE/C composite foam had an interconnected macropore structure and wettability of superhydrophobicity. Meanwhile, the porous skeleton of the PTFE/C composite foam showed a skin–core microstructure with the functional skin layer of PTFE continuous phase and the support core of PTFE and carbon in situ composite phase. The PTFE functional layer was anchored to the support composite layer in a root‐like branching, which endows the porous PTFE/C composite foam with an extremely durable performance. In gravity‐driven oil–water separation, the porous PTFE/C composite foam achieved considerable oil flux (from 27 174 to 73 242 L h−1 m−2) and purity (as high as 99.83 wt%). Meanwhile, the porous PTFE/C composite foam presented resistance to strong acids, strong alkalis, chemical solvents and friction. Even after it had been mechanically damaged, the superhydrophobic properties of the foam were not degraded. The as‐prepared porous PTFE/C composite foam showed great potential in all kinds of harsh environments. © 2021 Society of Industrial Chemistry.

Saturated adsorption of lidocaine and coal tar dyes onto porous polytetrafluoroethylene.

Polytetrafluoroethylene (PTFE) has excellent physical properties and has been used in a wide range of applications in various fields. Adsorption research on PTFE is essential as primary research for the further application of PTFE. We attempted to adsorb coal tar dyes and model drugs such as lidocaine onto PTFE as a guideline to search for medicines that adsorb onto PTFE. Saturation curves were obtained after analyzing the adsorption of coal tar dyes on PTFE using the Hanes–Woolf plot. In addition, we collected multiple cases of ATR-FTIR spectral changes and/or retention depending on TPM derivatives and other adsorbates. Lidocaine matched some coal tar dye for the apparent spectral changes between the adsorbed molecules and its crystalline powder. The apparent spectral changes are blue-shifted, suggesting a hydrophobic interaction between the dyes/lidocaine and porous PTFE. This work provides a promising strategy for further application of PTFE.

Porous superhydrophobic‐superoleophilic polytetrafluoroethylene fibrous membranes with tertiary structures for efficient oil/water separation

AbstractThe separation of stable oil/water emulsions is an urgent global issue. In this work, a porous and superhydrophobic polytetrafluoroethylene (PTFE) fibrous membrane was obtained by first centrifugal spinning PTFE/potato starch fibers and then heat treating the fibers to remove the starch. Results showed that spherical protrusions and irregular striped protrusions appeared on the surface of the prepared PTFE fibers, which significantly increased the roughness and hydrophobicity of the fibrous membrane. In addition, number density and shapes of these protrusions could be tuned by changing the extent of the heat treatment and the potato amylose content during the fiber preparation. The water contact angle on the structured PTFE membranes was as high as 160°, and the water sliding angle was as low as 3.4°. The results of oil/water separation experiments showed that the oil removal rate reached 99.5% based a permeability of 3670 L/m2/h, which suggested that the obtained PTFE fibrous membrane has great potential for use in oil/water emulsions separation.

Synthesis and Properties of Ion-Exchange Membranes Based on Porous Polytetrafluoroethylene and Sulphonated Polystyrene

Synthesis and Properties of Ion-Exchange Membranes Based on Porous Polytetrafluoroethylene and Sulphonated Polystyrene

Use of Biochar-Based Cathodes and Increase in the Electron Flow by Pseudomonas aeruginosa to Improve Waste Treatment in Microbial Fuel Cells

In this paper, we tested the combined use of a biochar-based material at the cathode and of Pseudomonas aeruginosa strain in a single chamber, air cathode microbial fuel cells (MFCs) fed with a mix of shredded vegetable and phosphate buffer solution (PBS) in a 30% solid/liquid ratio. As a control system, we set up and tested MFCs provided with a composite cathode made up of a nickel mesh current collector, activated carbon and a single porous poly tetra fluoro ethylene (PTFE) diffusion layer. At the end of the experiments, we compared the performance of the two systems, in the presence and absence of P. aeruginosa, in terms of electric outputs. We also explored the potential reutilization of cathodes. Unlike composite material, biochar showed a life span of up to 3 cycles of 15 days each, with a pH of the feedstock kept in a range of neutrality. In order to relate the electric performance to the amount of solid substrates used as source of carbon and energy, besides of cathode surface, we referred power density (PD) and current density (CD) to kg of biomass used. The maximum outputs obtained when using the sole microflora were, on average, respectively 0.19 Wm−2kg−1 and 2.67 Wm−2kg−1, with peaks of 0.32 Wm−2kg−1 and 4.87 Wm−2kg−1 of cathode surface and mass of treated biomass in MFCs with biochar and PTFE cathodes respectively. As to current outputs, the maximum values were 7.5 Am−2 kg−1 and 35.6 Am−2kg−1 in MFCs with biochar-based material and a composite cathode. If compared to the utilization of the sole acidogenic/acetogenic microflora in vegetable residues, we observed an increment of the power outputs of about 16.5 folds in both systems when we added P. aeruginosa to the shredded vegetables. Even though the MFCs with PTFE-cathode achieved the highest performance in terms of PD and CD, they underwent a fouling episode after about 10 days of operation, with a dramatic decrease in pH and both PD and CD. Our results confirm the potentialities of the utilization of biochar-based materials in waste treatment and bioenergy production.

Selectivity of vacuum ammonia stripping using porous gas-permeable and dense pervaporation membranes under various hydraulic conditions and feed water compositions

Recovery of ammonia (NH3) from residual waters offers various reuse opportunities, such as the production of fertilisers and the generation of electricity and heat. However, simultaneous evaporation of water (H2O) during NH3 stripping under vacuum results in diluted recovered NH3 gas with high H2O contents. Whereas porous gas-permeable membranes are already used for vacuum NH3 stripping, the use of non-porous silica-based pervaporation (PV) membranes showed promising results in recent literature, with respect to more selective transfer of NH3 compared to H2O. In this study, we assessed the selectivity of NH3 over H2O transfer (SNH3/H2O) for different types of membranes, under various hydraulic conditions and feed water compositions. The three following membranes were tested: a porous gas-permeable polytetrafluoroethylene (PTFE) membrane, a hydrophilic (Hybrid Silica PV) membrane and a hydrophobic polydimethylsiloxane PV (PDMS PV) membrane.For the PTFE and the Hybrid Silica PV membrane, SNH3/H2O ranged between 0.1 and 0.4, indicating that the transfer of NH3 was consistently less preferred compared to the transfer of H2O. The preference for H2O over NH3 transfer through the membranes at various hydraulic conditions and feed water compositions can be assigned to the similarity in polarity and kinetic diameter of NH3 and H2O and the low relative concentration of NH3 in the used feed waters (approximately 0.1–1.0 wt%). The PDMS PV membrane showed negligible NH3 transfer and deteriorated rapidly during the NH3 stripping experiments. The SNH3/H2O of both gas-permeable and PV membranes was higher for unsteady than for steady hydraulic conditions. Furthermore, the SNH3/H2O of the both PTFE and the Hybrid Silica decreased when the ionic strength of the feed water increased from 0.0 to 0.8 mol∙L−1 and when the NH3 feed water concentration increased from 1 to 10 g∙L−1. According to the results, the used PV membranes did not show selectivity of NH3 over H2O transfer. In fact, the used PV membranes consistently had a lower SNH3/H2O than the PTFE membrane. Hence, the dense silica-based PV membranes did not allow for the recovery of gaseous NH3 from water, with lower H2O content in the recovered gas, compared to porous PTFE membranes.

Monolithic polymeric porous superhydrophobic material with pneumatic plastron stabilization for functionally durable drag reduction in blood-contacting biomedical applications

Superhydrophobic (SHP) surfaces can provide substantial reductions in flow drag forces and reduce blood damage in cardiovascular medical devices. However, strategies for functional durability are necessary, as many SHP surfaces have low durability under abrasion or strong fluid jetting or eventually lose their air plastron and slip-flow capabilities due to plastron gas dissolution, high fluid pressure, or fouling. Here, we present a functional material that extends the functional durability of superhydrophobic slip flow. Facile modification of a porous superhydrophobic polytetrafluoroethylene (PTFE, Teflon) foam produced suitable surface structures to enable fluid slip flow and resist protein fouling. Its monolithic nature offered abrasion durability, while its porosity allowed pressurized air to be supplied to resist fluid impalement and to replenish the air plastron lost to the fluid through dissolution. Active pore pressure control could resist high fluid pressures and turbulent flow conditions across a wide range of applied pressures. The pneumatically stabilized material yielded large drag reductions (up to 50%) even with protein fouling, as demonstrated from high-speed water jetting and closed loop pressure drop tests. Coupled with its high hemocompatibility and impaired protein adsorption, this easily fabricated material can be viable for incorporation into blood-contacting medical devices.

Advanced hybrid membrane for vanadium redox flow battery created by polytetrafluoroethylene layer and functionalized silicon carbide nanowires

As a key component of vanadium redox flow battery (VRFB), ion exchange membrane determines the performance of VRFB, wherein commercial membrane (such as Nafion) exacerbate problems including high permeability of vanadium ions and poor cyclic stability. In this study, a low vanadium ion permeation hybrid membrane is developed by dispersing functionalized silicon carbide nanowires in perfluorinated sulfonic acid (PFSA) matrix and sandwiching an ultrathin porous polytetrafluoroethylene (PTFE) layer. This hybrid membrane greatly improves the performance of VRFB cell exhibiting good Coulombic efficiency (up to 96.2%) and high energy efficiency (up to 87.1%) at 120 mA cm−2, contrasted with the Nafion 212 membrane (91.3% and 79.8%). Furthermore, a single cell with the hybrid membrane possesses ultra-stable cyclicity (1000 cycles, over 233.4 h). This can be assigned to the unique structure of the membrane in which the functionalized nanowires are uniformly dispersed in PFSA matrix to sandwich an ultra-thin PTFE layer to block or lengthen the diffusion paths of vanadium ions, while the functionalized groups on the surface of the rigid nanowires facilitate protons transportation. This strategy of reshaping membrane may serve in relative fields including proton exchange membrane fuel cells and water treatment.

Desorption characteristic of LiBr–H2O solution in hydrophobic hollow fiber membrane for absorption chiller

• A PTFE membrane module is used as a desorber in an absorption refrigeration system. • Water vapor transports through a hollow fiber membrane by Knudsen diffusion. • A concentration difference of about 0.4% is achieved with a tiny membrane desorber. The membrane-based desorber is considered a promising alternative to miniaturize the present generator in the absorption refrigeration system, owing to its large specific interfacial area, which is expected to reduce the required volume for the unit of cooling capacity of the system. The heat and mass transfer characteristics of a desorber consisting of a porous polytetrafluoroethylene hollow fiber membrane were evaluated by both experiment and simulation under practical working conditions. The Knudsen diffusion was verified by a gas permeability test prior to the water vapor desorption test. According to the desorption experiment results of the LiBr-H 2 O solution, a concentration difference of approximately 0.4% was achieved under the investigated conditions. The results also indicated that an increase in the solution flowrates leads to an increase in the water vapor desorption rate owing to the increase of sensible heat. The compared simulation and experimental results were consistent with an acceptable accuracy. This study provides a fundamental understanding of the heat and mass transfer of the membrane-based desorber, which benefits the design of the compact membrane-based absorption refrigeration systems.

Fabrication and Characterization of Flexible Capacitive Humidity Sensors Based on Graphene Oxide on Porous PTFE Substrates.

Porous polytetrafluoroethylene (PTFE) is physically flexible, thermally and chemically stable, relatively inexpensive, and commercially available. It is attractive for various flexible sensors. This paper has studied flexible capacitive humidity sensors fabricated on porous PTFE substrates. Graphene oxide (GO) was used as a sensing material, both hydrophobic and hydrophilic porous PTFE as the substrates, and interdigitated electrodes on the PTFE substrates were screen-printed. SEM and Raman spectrum were utilized to characterize GO and PTFE. An ethanol soak process is developed to increase the yield of the humidity sensors based on hydrophobic porous PTFE substrates. Static and dynamic properties of these sensors are tested and analyzed. It demonstrates that the flexible capacitive humidity sensors fabricated on the ethanol-treated hydrophobic PTFE exhibit high sensitivity, small hysteresis, and fast response/recovery time.

Pore-Filled Proton-Exchange Membranes with Fluorinated Moiety for Fuel Cell Application

Proton-exchange membrane fuel cells (PEMFCs) are the heart of promising hydrogen-fueled electric vehicles, and should lower their price and further improve durability. Therefore, it is necessary to enhance the performances of the proton-exchange membrane (PEM), which is a key component of a PEMFC. In this study, novel pore-filled proton-exchange membranes (PFPEMs) were developed, in which a partially fluorinated ionomer with high cross-linking density is combined with a porous polytetrafluoroethylene (PTFE) substrate. By using a thin and tough porous PTFE substrate film, it was possible to easily fabricate a composite membrane possessing sufficient physical strength and low mass transfer resistance. Therefore, it was expected that the manufacturing method would be simple and suitable for a continuous process, thereby significantly reducing the membrane price. In addition, by using a tri-functional cross-linker, the cross-linking density was increased. The oxidation stability was greatly enhanced by introducing a fluorine moiety into the polymer backbone, and the compatibility with the perfluorinated ionomer binder was also improved. The prepared PFPEMs showed stable PEMFC performance (as maximum power density) equivalent to 72% of Nafion 212. It is noted that the conductivity of the PFPEMs corresponds to 58–63% of that of Nafion 212. Thus, it is expected that a higher fuel cell performance could be achieved when the membrane resistance is further lowered.

Facile Screen-Printed Carbon Nanotube Electrode on Porous Substrate with Gold Nanoparticle Modification for Rapid Electrochemical Gas Sensing

Gas sensors have attracted extensive attentions due to their vital roles in various applications. However, gas sensors featuring long lifetime, fast response and low cost still remain challenging. This paper presents a facile screen-printed carbon nanotube electrode on porous polytetrafluoroethylene (PTFE) with room temperature ionic liquid (RTIL) for rapid gas sensing. Screen printing technique was implemented on porous PTFE substrate to form three-electrode system using carbon nanotube ink and silver ink. Thus, gases can directly diffuse through the porous substrate rather than supporting electrolyte for rapid detection. RTIL was utilized as the supporting electrolyte that ensures long sensor lifetime. With gold nanoparticles modification, the sensor exhibited enhanced electrochemical performance for gas detection. Chronoamperometry was conducted to evaluate the sensor performance from 2.1% oxygen to 12.6% oxygen, validating good sensitivity and linearity. The sensor also presented good repeatability, stability and reproducibility in the tests. Due to the unique porous substrate of the sensor, the response time can be as low as ∼14 s that achieves rapid oxygen sensing. In summary, the sensor was validated with satisfactory performance, which is promising for wearable gas sensing and acute gas exposure alerting.

Robust Hierarchical Porous PTFE Film Fabricated via Femtosecond Laser for Self-Cleaning Passive Cooling.

Passive cooling materials that spontaneously cool an object are promising choices for mitigating the global energy crisis. However, these cooling effects are usually weakened or lost when dust contaminates the surface structure, greatly restricting their applications. In this work, a robust hierarchical porous polytetrafluoroethylene (PTFE) film with coral-like micro/nanostructures is generated by a facile and efficient femtosecond laser ablation technique. Owing to its unique micro/nanostructures, the as-prepared surface exhibits an outstanding self-cleaning function for various liquids with ultralow adhesion. This self-cleaning characteristic enhances the durability of its passive cooling effect. It is demonstrated that the titanium (Ti) sheet covered with laser-ablated PTFE film can realize a maximum temperature decrease of 4 and 10 °C compared to the Ti sheet covered with pristine PTFE film and uncovered, respectively. This study reveals that femtosecond laser micromachining is a facile and feasible avenue to produce robust self-cleaning passive cooling devices.

A rapid hydrophilization of porous poly(tetrafluoroethylene) film via co-deposition of phenol derivatives and polyethyleneimine

A series of hydrophilized porous polytetrafluoroethylene (PTFE) membranes were prepared by a mussel-inspired coating method. Various types of phenol derivatives possessing different number of hydroxide groups at different position such as hydroquinone, pyrogallol, hydroxyhydroquinone were applied along with polyethyleneimine (PEI) to seek for the fast and stable surface modification. The co-deposition kinetics of phenol/PEI pair on the porous PTFE membranes was examined using the ultraviolet spectroscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. Surface morphology and pore diameter were analyzed by the field emission scanning electron microscopy and mercury porosimetry. To confirm the complete surface hydrophilicity, water contact angle was measured as a function of time for different co-deposition pairs. Among several phenol derivatives paired with PEI, hydroxyhydroquinone showed the fastest deposition rate (in about 40 min) for excellent hydrophilicity and stability. The chemical modification method applied in this study showed the long-term stability in commonly used and harsh solvents including acidic and basic solutions compared to the other physical and chemical methods previously reported.

Characterization and Determination of the Biocompatibility of Porous Polytetrafluoroethylene Membranes Fabricated via Electrospinning

The structure and properties of polytetrafluoroethylene (PTFE) polymeric membranes obtained by electrospinning from a suspension of PTFE in a solution of polyvinyl alcohol (PVA) with subsequent thermal treatment were presented. The effect of the PTFE suspension ratio in spinning solutions on the morphology, crystal structure, chemical composition, strength, and cytotoxicity of the formed PTFE membranes was evaluated. We found that a decrease in the PTFE suspension content in spinning solutions leads to a decrease in the number of defects in the membrane fibers, which increasing the strength and elongation. Membranes made from spinning solutions with a lower content of PTFE suspension have a higher degree of crystallinity and a more perfect crystal structure. It has been suggested that the products of PVA destruction during the heat treatment of PTFE/PVA membranes are capable of plasticizing effects on PTFE particles, improving the strength of PTFE membranes. The membranes after thermal treatment were not cytotoxic regardless of the PTFE suspension content in the spinning solutions. High biocompatibility of membranes was established during implantation into soft tissues.

Alcohol-Treated Porous PTFE Substrate for the Penetration of PTFE-Incompatible Hydrocarbon-Based Ionomer Solutions.

For a mechanically tough proton exchange membrane, a composite membrane incorporated with a porous polymer substrate is of great interest to suppress the ionomer swelling and to improve the dimensional stability and mechanical strength of the ionomers. For the composite membranes, good impregnation of substrate-incompatible ionomer solution into the substrate pores still remains one of the challenges to be solved. Here, we demonstrated a facile process (surface treatment with solvents compatible with both substrate and the ionomer solution) for the fabrication of the composite membranes using polytetrafluoroethylene (PTFE) as a porous substrate and poly(arylene ether sulfone) (SPAES) as a hydrocarbon-based (HC) ionomer. Appropriate solvents for the surface treatment were sought through the contact angle measurement, and it was found that alcohol solvents effectively tuned the surface property of PTFE pores to facilitate the penetration of the SPAES/N-methyl-2-pyrrolidone (NMP) solution into ∼300 nm pores of the substrate. Using this simple alcohol treatment, the SPAES/NMP contact angle was reduced in half, and we could fabricate the mechanically tough PTFE/HC composite membranes, which were apparently translucent and microscopically almost void-free composite membranes.

Simple and scalable synthesis of super-repellent multilayer nanocomposite coating on Mg alloy with mechanochemical robustness, high-temperature endurance and electric protection

Multi-functionalization is the future development direction for protective coatings on metal surface, but has not yet been explored a lot. The effective integration of multiple functions into one material remains a huge challenge. Herein, a superhydrophobic multilayer coating integrated with multidimensional organic-inorganic components is designed on magnesium alloy via one-step plasma-induced thermal field assisted crosslinking deposition (PTCD) processing followed by after-thermal modification. Hard porous MgO ceramic layer and polytetrafluoroethylene (PTFE) nano-particles work as the bottom layer skeleton and filler components separately, forming an organic-inorganic multilayer structure, in which organic nano-particles can be crosslinked and cured to form a compact polymer-like outer layer with hierarchical surface textures. Remarkably, the chemical robustness after prolonged exposure to aqua regia, strong base and simulated seawater solution profits from polymer-like nanocomposite layer uniformly and compactly across the film bulk. Moreover, the self-similar multilayer structure coating endows it attractive functions of strong mechanical robustness (>100th cyclic rotary abrasion), stable and ultra-low friction coefficient (about 0.084), high-temperature endurance, and robust self-cleaning. The organic-inorganic multilayer coating also exhibits high insulating property with breakdown voltage of 1351.8 ± 42.4 V, dielectric strength of 21.4 ± 0.7 V/µm and resistivity of 3.2 × 1010 Ω·cm. The excellent multifunction benefits from ceramic bottom skeleton, the assembly and deposition of multidimensional nano-particles, and the synergistic effect of organic inorganic components. This study paves the way for designing next generation protective coating on magnesium alloy with great potential for multifunctional applications.

Porous PTFE reinforced SPEEK proton exchange membranes for enhanced mechanical, dimensional, and electrochemical stability

The pores of polytetrafluoroethylene (PTFE) film were filled with the sulfonated poly (ether ketone) (SPEEK) electrolyte molecules to prepare the proton exchange membrane with the enhanced mechanical, dimensional and electrochemical stability for fuel cell application. Catechol/polyethyleneimine was co-deposited on the PTFE pore surface as an adhesive mediator for the feasible impregnation of SPEEK. The chemical composition, morphology, and wettability of the porous PTFE film were investigated by electron spectroscopy for chemical analysis, scanning electron microscope, mercury porosimetry, and water contact angle measurements. After pore filling with SPEEK electrolytes, several essential properties of membranes (e.g. water uptake, proton conductivity, mechanical property) and wet/dry cyclic cell performance were examined. The prepared pore-filled electrolyte membranes showed the superior mechanical and dimensional stability at the reduced water uptake to the pristine SPEEK membrane. Those excellent properties of the electrolyte membranes are reflected in the stable electrochemical cell performance over the repeated wet/dry cycles with suppression of crack/void formation and edge breakdown.