Macromolecular Rapid Communications最新文献

Electrospun polystyrene (PS) fibers are produced using a mixed solvent of chloroform and n,n-dimethylformamide (DMF) to investigate the influence of the solvent ratio on the fiber surface morphology and contact angle of the obtained mats. Electrospinning is a simple processing technique for producing fibers with diameters in the range of nanometers to a few micrometers. When using the different solvent ratios for this process, porous PS membranes are created due to nonsolvent and thermally induced phase separation (N-TIPS). The morphology of the fibers is analyzed through scanning electron microscopy (SEM), which showed that fibers have diameters between 200 nm and 6 µm. SEM also revealed that the pores present on the surface of the fibers vary from densely compacted and well-formed nanopores with diameters in the range of 20–50 nm to larger pores with sizes of ≈100–200 nm. The pore size varied with different solvent ratios. The surface area is analyzed using the Brunauer–Emmett–Teller (BET) method and found that the polymeric fibers have a high surface area (≈35 m² g⁻¹). The fibers with such morphology are highly hydrophobic, with a contact angle higher than 143°. These materials are excellent candidates for applications in textiles, filtration, and biomedical fields.

Biomimetic slippery liquid-infused porous surfaces (SLIPS) have emerged as a promising solution to solve the limitations of superhydrophobic surfaces, such as inadequate durability in corrosion protection and a propensity for frosting. However, the challenge of ensuring strong, lasting adhesion on diverse materials to enhance the durability of the lubricant layer remains. The research addresses this by leveraging amyloid phase-transitioned lysozyme (PTL) as an adhesive interlayer, conferring stable attachment of SLIPS across a variety of substrates, including metals, inorganics, and polymers. The silica-textured interface robustly secures the lubricant with a notably low sliding angle of 1.15°. PTL-mediated adhesion fortifies the silicone oil attachment to the substrate, ensuring the retention of its repellent efficacy amidst mechanical stressors like ultrasonication, water scrubbing, and centrifugation. The integration of robust adhesion, cross-substrate compatibility, and durability under stress affords the PTL-modified SLIPS exceptional anti-fouling, anti-icing, and anti-corrosion properties, marking it as a leading solution for advanced protective applications.

Chemical reactions and transformations in non-traditional vessels have gained significant interest in recent years. Flow chemistry, with its advantages in mixing, mass transfer, scalability, and automation, is a driving force behind this paradigm shift. In particular, the Vortex Fluidic Device (VFD) has emerged as a versatile tool across various applications, from organic synthesis to materials science. In this study, the role of the VFD in performing the Biginelli reaction, a multicomponent reaction widely used in pharmaceutical and polymer science, for a post-polymerization modification is explored. By conducting the Biginelli reaction in the VFD, rapid product formation with low catalyst loading and without the need for high temperatures is achieved. However, the critical need to understand and know solution viscosity, especially within the context of modifying macromolecules is highlighted.

Current wood identification struggles to differentiate white and red oak (Quercus alba and Quercus rubra) due to highly similar microstructures, as demonstrated by morphological microscope analysis. The present research explores lignin composition as a potential discriminating factor. Here, a rapid and sustainable method for extracting high-quality lignin from oak samples using acidic γ-valerolactone (GVL) under mild conditions is described. As-extracted lignin is thoroughly characterized using various analytical methods, and results reveal a distinct structural difference between the lignin from the two species. White oak lignin possesses a unique "Hibbert ketone" unit detectable by nuclear magnetic resonance spectroscopy (NMR), which is absent in red oak lignin. In addition, infrared spectroscopy differentiates the species based on specific carbonyl groups present in their lignin. These findings suggest that identifying the presence of the Hibbert ketone unit in lignin may offer a highly efficient and reliable method for differentiating white and red oak, opening new avenues for wood identification.

In the previous study (Green Chem., 2023, 25, 3418), highly stretchable and mechanically tough poly(methyl acrylate) (pMA) microparticle-based elastomers can be formed by drying a microparticle-containing aqueous dispersion. This discovery has the potential to overcome the mechanical weakness of industrially produced aqueous latex films. However, in 3D-arranged particle films, structural complexity, such as the existence of defects, makes it difficult to clearly understand the relationship between the particle film structure and its mechanical properties. In this study, 2D-ordered pMA particle monolayers at the air/water interface of a Langmuir trough are prepared. Under high compression at the air/water interface, the microparticles contact their neighboring particles, and the resulting monolayers can be successfully transferred onto a solid substrate. The compression of the monolayer films is linked to an increase in the elastic modulus of the monolayer film on the solid substrate as evident from the local Young's modulus mapping using atomic force microscopy. Thus, pMA particle films with different mechanical properties can be created using a Langmuir trough.

Cotton fabrics with the main constituent of cellulose, which is hydrophilic, bacterial infected, and flammable, are in urgent need of functionalization as a kind of widely applied material. To address these issues, in this work, modified polyelectrolyte complex (MPEC) coatings with polyethylenimine (PEI), polyphosphate (APP), and perfluorodecyltrichlorosilane modified PEI (PFTS-PEI) are prepared to construct multi-functionally gradient MPEC coatings on cotton fabrics. Stability and synergistic effects on hydrophobicity, antibacterial activity, and flame retardancy in this system have been studied. Notably, PFTS-PEI with fluorine and silicone elements are confirmed to provide hydrophobicity and durability for MPEC coatings, which not only has no negative effect on other functions but also makes some improvement in antibacterial activity. This MPEC-treated cotton fabric finally has an antibacterial rate against S. aureus and E. coli of 99.9% and 96.9%, limiting oxygen index of 28.5% and water contact angle of 118°, which can be almost maintained after 20 times washing. The modified PEC will provide an efficient strategy to achieve durable multi-functions on cellulose-based fabrics.

Amino-acid-derived polyzwitterions and polybetaines (PBs) are two promising alternatives to non-ionic polymers, for example, to increase tumor permeability. In this study, amino-acid-derived polyzwitterions are synthesized and a strategy to quarternize the amine in the side chain functional group is developed to combine the advantages of both types. The functional monomer is polymerized via reversible addition-fragmentation chain-transfer polymerization for which a kinetic study is performed. Further, the impact of the permanent positive charge on amino-acid-derived polyzwitterions is studied based on two zwitterionic polymers obtained via post-polymerization modification (PPM) of Poly(N-acryloxysuccinimide) to allow good comparison between methylated and non-methylated polymers. Circular dichroism shows that the stereocenter remains intact during PPM. pH titration and ζ-potential measurements show that the methylated polymer has a negative ζ-potential over the measured pH range and, therefore, the polymer remains zwitterionic over a broader pH range than its non-methylated equivalent. Both polymers are well tolerated by mammalian cells up to concentrations of 1 mg mL^-1. The study introduces a path to a new polymer class that combines the advantages of both PBs and amino-acid-derived polyzwitterions and highlights the impact a permanent charge has on the physiochemical properties.

Photomediated reversible addition fragmentation chain transfer (RAFT) step-growth polymerization is performed using a trithiocarbonate-based chain transfer agent (CTA) and acrylate-based monomers both with and without a photocatalyst. The versatility of photo-mediated RAFT step-growth is demonstrated by one-pot synthesis of a graft copolymer via sequential monomer addition. Furthermore, oxygen-tolerant photo-mediated RAFT step-growth is demonstrated, facilitated by the appropriate selection of photocatalyst and solvent pair (zinc tetraphenyl porphyrin [ZnTPP] and dimethyl sulfoxide [DMSO]), enabling ultralow volume polymerization under open-air conditions.

Front Cover: A versatile platform is developed for creating functional π-conjugated organic nanoparticles stabilized by amphiphilic block copolymers for green H₂ photocatalytic generation. The donor–acceptor–donor trimers nanoparticles show enhanced photocatalytic activity (≈0.6 mmol g⁻¹ h⁻¹) for H₂ production via water splitting. More details can be found in article 2400395 by Thiago R. Guimarães, Jean-Louis Bobet, Eric Cloutet, and co-workers.