Composite polymeric membranes were designed based on sulfonated poly(ether ether sulfone) (sPEES) and mesostructured cellular foam (MCF) silica nanoparticles functionalized with organic compounds. Parameters such as molecular weight (MW) of the polymer, nature of the functional group of the MCF silica, and percentage of silica charge were evaluated on the final properties of the membranes. Composite membrane characterization was carried out on their water retention capacity (high MW polymer between 20-46% and for the low MW between 20-60%), ion exchange capacity (IEC) (high MW polymer between 0.02 mmol/g-0.07 mmol/g and low MW between 0.03-0.09 mmol/g) and proton conductivity (high MW polymer molecular between 15-70 mS/cm and low MW between 0.1-150 mS/cm). Finally, the membrane prepared with the low molecular weight polymer and 3% wt. of functionalized silica with sulfonic groups exhibited results similar to Nafion 117.
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http://dx.doi.org/10.3390/membranes12111075 | DOI Listing |
J Am Chem Soc
January 2025
Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, United States.
Enthalpy is often the focal point when designing monomers for polymer circularity, but much less is explored on how entropy can be exploited to create polymers with synergistic circularity and properties. Here, we design a series of spiro-lactones (SLs) with closed-chain cycloalk(en)yl substituents at the α,α-position of δ-valerolactone (δVL), which, when combined with the parent δVL and -α,α-dialkyl-substituted δVL with open-chain alkyl groups, provide a desired platform for exploring the circular polymer design by focusing on the entropy change of polymerization. These SLs exhibit finely balanced (de)polymerizability that is regulated chiefly by entropy differentiation, allowing both the facile synthesis of polyester PSLs ( up to 1000 kg mol) in a living fashion and selective depolymerization of the PSLs to completely recover monomers under mild conditions (using a recyclable catalyst at 100 °C).
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Department of Physics, School of Electrical and Electronics Engineering, SASTRA Deemed to be University, Thanjavur 613 401, Tamil Nadu, India.
This study presents the fabrication of highly conducting Au fabric electrodes using a layer-by-layer (LBL) approach and its application toward energy storage. Through the ligand-exchange mechanism, the alternating layers of tris(2-aminoethyl)amine (TREN) and gold nanoparticles (Au NPs) encapsulated with tetraoctylammonium bromide (TOABr) ligands (Au-TOABr) were deposited onto the fabric to achieve a highly conducting Au fabric (0.12 Ω/□) at room temperature in just two LBL cycles.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
The aging population necessitates a critical need for medical devices, where polymers-based surface lubrication coating is essential for optimal functionality. In fact, lubrication and mechanical requirements vary depending on the service environment of different medical devices. Until now, key mean is still blank for general preparation of hydrophilic polymers-based lubrication coatings with on-demand mechanics and lubricity.
View Article and Find Full Text PDFMater Horiz
January 2025
Key Laboratory of Polymer Processing Engineering of the Ministry of Education, National Engineering Research Center of Novel Equipment for Polymer Processing, Guangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced Manufacturing, South China University of Technology, Guangzhou 510641, People's Republic of China.
Passive daytime radiative cooling offers a promising approach to address energy, environmental, and safety issues caused by global warming. However, the contradiction between high radiative cooling performance and long-lasting ultraviolet (UV) durability is a primary limitation at the current stage. Here, inspired by the ability of epidermal cells and palisade cells on the leaf surface to protect internal leaf structures (such as chloroplasts and nuclei) under drought and high-temperature conditions, a double-layer passive radiative cooling (PRC) porous membrane, which consists of an upper protective layer densely packed with highly ultraviolet-reflective inorganic particles and a bottom cooling layer doped with a variety of optically characterized inorganic particles, was developed to overcome these challenges.
View Article and Find Full Text PDFCNS Neurosci Ther
January 2025
Children's Medical Center, Department of Pediatric Neurology, Peking University First Hospital, Beijing, China.
Aims: Alexander disease (AxD) is a leukodystrophy caused by mutations in the astrocytic filament gene GFAP. There are currently no effective treatments for AxD. Previous studies have rarely established AxD models with the patient's original GFAP mutations.
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