Colored cotton fabrics with satisfactory color fastness as well as durable antibacterial and self‐healing superhydrophobic properties are fabricated via a convenient solution‐dipping method that involves the sequential deposition of branched poly(ethylenimine) (PEI), silver nanoparticles (AgNPs), and fluorinated decyl polyhedral oligomeric silsesquioxane (F‐POSS) on cotton fabrics. The deposited AgNPs with tunable surface plasmon resonance endow the cotton fabrics with abundant color and and antibacterial ability. However, in general, water‐soluble AgNPs cannot be firmly deposited onto cotton fabrics to endure the laundering process. The integration of self‐healing superhydrophobicity into the cotton fabrics by depositing F‐POSS/AgNP/PEI films significantly enhances the color fastness of the AgNPs against laundry and mechanical abrasion, while retaining the antibacterial property of the AgNPs. The F‐POSS/AgNP/PEI‐coated cotton fabric accommodates an abundance of F‐POSS, which autonomically migrates to the cotton surface to repetitively restore its damaged superhydrophobicity. The self‐healing superhydrophobicity of the F‐POSS/AgNPs/PEI‐coated cotton fabric guarantees long‐term protection of the underlying AgNPs against laundry and abrasion and allows the cotton fabric to be cleaned by simple rinsing with water.
Highly transparent polymeric antifogging and frostresisting films capable of conveniently healing scratches and cuts are fabricated by the dip-coating technique from a solution of hydrogenbonded poly(vinyl alcohol) (PVA) and Nafion complexes (denoted as PVA−Nafion), and then the as-prepared PVA−Nafion films are soaked in an aqueous NaOH solution to induce the formation of PVA crystallites. The dip-coated PVA−Nafion films can be deposited on plastic substrates such as poly(ethylene terephthalate) and polycarbonate eyeglasses and are sufficiently flexible to endure repeated bending−unbending treatments. The PVA crystallites act as physical cross-linkers and significantly improve the stability of the PVA−Nafion antifogging films in water. Nafion has a hydrogen-bonding interaction with PVA that further improves the stability of the PVA−Nafion films. The excellent antifogging and frost-resisting capabilities of the PVA−Nafion films even under aggressive fogging and frosting conditions originate from the remarkable water-absorbing capacity of PVA in the films. The reversible hydrogen-bonding interactions between PVA and Nafion and the high mobility of the polymer chains triggered by water endow the PVA−Nafion films with the ability to rapidly and repeatedly heal scratches and cuts several hundreds of micrometers wide to restore their high transparency as well as antifogging and frost-resisting functions.
Antifouling polymeric films can prevent undesirable adhesion of bacteria but are prone to accidental scratches, leading to a loss of their antifouling functions. To solve this problem, we report the fabrication of healable antifouling polymeric films by layer-by-layer assembly of partially hydrolyzed poly(2-ethyl-2-oxazoline) (PEtOx-EI-7%) and poly(acrylic acid) (PAA) based on hydrogen-bonding interaction as the driving force. The thermally cross-linked (PAA/PEtOx-EI-7%)*100 films show strong resistance to adhesion of both Gram-negative Escherichia coli and Gram-positive Bacillus subtilis bacteria due to the high surface and bulk concentration of the antifouling polymer PEtOx-EI-7%. Meanwhile, the dynamic nature of the hydrogen-bonding interactions and the high mobility of the polymers in the presence of water enable repeated healing of cuts of several tens of micrometers wide in cross-linked (PAA/PEtOx-EI-7%)*100 films to fully restore their antifouling function.
The first case of selective Fe(3+) ions and 1,4-dioxane luminescent sensor based on a porous organic polymer, POP-HT, was synthesized by reaction of tetra(p-aminophenyl)methane and chromophoric 2,5,8-trichloro-s-heptazine. POP-HT displayed prominent fluorescence quenching or enhancement in the presence of Fe(3+) ion or 1,4-dioxane. Moreover, an excellent linear relationship was established between luminescent intensity and the corresponding Fe(3+) ion or 1,4-dioxane concentration. The mechanisms of luminescence quenching and enhancement were also studied by both experiment and theoretical calculation. The results of this study suggest that POP-HT can work as an effective luminescent indicator for qualitative and quantitative detection of Fe(3+) ions and 1,4-dioxane in aqueous solution over other metal ions and organic solvents.
It remains a challenge to fabricate sacrificial films that are stable in most of solvents and can be readily decomposed on demand. Here we report the fabrication of a near-infrared (NIR) light decomposable sacrificial film by layer-by-layer (LbL) assembly of UV-light-decomposable poly((4-(2-bromoethoxy)-5-methoxy-2-nitrobenzyl acrylate) triethylammonium bromide) (PNBA-TEA), poly(sodium 4-styrene-sulfonate) (PSS), branched polyethyleimine (bPEI), and lanthanide-doped upconversion nanoparticles (UCNPs). The [(PNBA-TEA/PSS)*2/(bPEI/UCNPs)*3]*2 films are stable in deposition solutions of various materials and decompose upon NIR light irradiation. In the [(PNBA-TEA/PSS)*2/(bPEI/UCNPs)*3]*2 films, UCNPs can convert NIR light into UV light, which can decompose PNBA-TEA. After immersing the NIR light-irradiated [(PNBA-TEA/PSS)*2/(bPEI/UCNPs)*3]*2 films in 0.1 M aqueous NaHCO3 solution, the disintegration of the entire films occurs because of the repulsive force between the negatively charged photoproduct of PNBA-TEA and PSS. LbL-assembled (PAH/PAA)*50 films deposited on top of the NIR-light-decomposable [(PNBA-TEA/PSS)*2/(bPEI/UCNPs)*3]*2 films can be conveniently released to produce large-area and defect-free (PAH/PAA)*50 free-standing films after NIR light irradiation and subsequent immersion in 0.1 M aqueous NaHCO3 solution. Because of the satisfactory stability and on-demand decomposable property, the [(PNBA-TEA/PSS)*2/(bPEI/UCNPs)*3]*2 films are promising as sacrificial layers for the fabrication of various free-standing films.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.