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Polymers containing biocidal moieties (e.g., amino or ammonium groups) are considered promising materials that can help combat the growing resistance of pathogens to commonly used antimicrobials. Searching for new polymeric biocides, in this work, non-porous and porous poly(hydromethylsiloxane) (PHMS) networks were prepared and post-functionalized by N-allylaniline (Naa). Non-porous networks were obtained by cross-linking PHMS in the bulk and porous—in W/O high-internal-phase emulsion (HIPE). Linear divinyldisiloxane (M2Vi) or cyclic tetravinyltetrasiloxane (D4Vi) were used as cross-linkers. Studies confirmed the expected non-porous and open macroporous microstructure of the initial networks. They also showed that functionalization by Naa was more efficient for the non-porous networks that swelled to lower extents in toluene and contained higher amounts of Si-H groups than the porous ones. In the reactions with benzyl chloride or 1-bromoctane, some amino groups present in these materials were transformed to ammonium groups. It was found that activity against Gram-positive S. aureus and Gram-negative E. coli bacteria depended on the functionalization degree, cross-linking level and the microstructure of the modified materials.

General information concerning different kinds of chemical additives used in the textile industry has been described in this paper. The properties and applications of organofunctional silanes and polysiloxanes (silicones) for chemical and physical modifications of textile materials have been reviewed, with a focus on silicone softeners, silane, and silicones-based superhydrophobic finishes and coatings on textiles composed of silicone elastomers and rubbers. The properties of textile materials modified with silanes and silicones and their practical and potential applications, mainly in the textile industry, have been discussed.

The branching and cross-linking of siloxane polymers are important processes in silicone technology. A new type of such a process has been developed, which is a self-restructuring of linear polyhydromethylsiloxane (PHMS). This process involves the reorganization of the PHMS to form a highly branched siloxane polymer or finally a cross-linked siloxane network. It occurs through the transfer of a hydride ion between silicon atoms catalyzed by tris(pentafluoromethyl)borane. Its advantage over existing branching and cross-linking reactions is that it runs at room temperature without a low-molecular-weight cross-linker in the absence of water, silanol groups, or other protic compounds and it does not use metal catalysts. The study of this process was carried out in toluene solution. Its course was followed by 1H NMR, 29Si NMR and FTIR, SEC, and gas chromatography. A general mechanism of this new self-restructuring process supported by quantum calculations is proposed. It has been shown that a linear PHMS self-restructured to a highly branched polymer can serve as a pure methylsiloxane film precursor.

This study investigates the synthesis, physicochemical characterization, and emulsifying performance of multifunctional polysiloxane modified with trimethoxysilane, eugenol and octane in varying molar ratios. The functionalized organosilicon compounds were synthesized by hydrosilylation and characterized using NMR, FT-IR, thermogravimetric analysis, and contact angle measurements. Their emulsifying properties were evaluated in oil-water emulsions, with stability assessed through centrifugation tests, multiple light scattering, and optical microscopy. The polysiloxane modified with trimethoxysilane: eugenol: octane with a 1:4:3 molar ratio exhibited the highest thermal stability. Emulsions formulated with this compound demonstrated superior physical stability, with backscattering destabilization rates as low as − 0.29%/day, attributed to enhanced interfacial interactions and hydrogen bonding. Emulsion containing polysiloxane modified only with eugenol and octane exhibited the lowest stability, with early phase separation observed after 1.5 h and backscattering rates reaching − 1.06%/day. These results highlight the critical role of silane functionalities in interfacial stabilization. These findings demonstrate the potential of structurally tailored polysiloxanes as advanced emulsifiers for applications in cosmetics, pharmaceuticals, and other industries.

There is an urgent need for developing electromechanical sensor with both ultralow detection limits and ultrahigh sensitivity to promote the progress of intelligent technology. Here we propose a strategy for fabricating a soft polysiloxane crosslinked MXene aerogel with multilevel nanochannels inside its cellular walls for ultrasensitive pressure detection. The easily shrinkable nanochannels and optimized material synergism endow the piezoresistive aerogel with an ultralow Young’s modulus (140 Pa), numerous variable conductive pathways, and mechanical robustness. This aerogel can detect extremely subtle pressure signals of 0.0063 Pa, deliver a high pressure sensitivity over 1900 kPa −1 , and exhibit extraordinarily sensing robustness. These sensing properties make the MXene aerogel feasible for monitoring ultra-weak force signals arising from a human’s deep-lying internal jugular venous pulses in a non-invasive manner, detecting the dynamic impacts associated with the landing and take-off of a mosquito, and performing static pressure mapping of a hair. The fabrication of pressure sensors with both ultralow detection limits and ultrahigh sensitivity is still challenging. Here, the authors propose a design strategy for fabricating a soft polysiloxane crosslinked MXene aerogel with multilevel nanochannels inside its cellular walls for ultrasensitive pressure detection.

Membrane distillation (MD) is an emerging desalination technology that exploits phase change to separate water vapor from saline based on low-grade energy. As MD membranes come into contact with saline for days or weeks during desalination, membrane pores have to be sufficiently small (typically <0.2 µm) to avoid saline wetting into the membrane. However, in order to achieve high distillation flux, the pore size should be large enough to maximize transmembrane vapor transfer. These conflicting requirements of pore geometry pose a challenge to membrane design and currently hinder broader applications of MD. To address this fundamental challenge, we developed a super liquid-repellent membrane with hierarchical porous structures by coating a polysiloxane nanofilament network on a commercial micro-porous polyethersulfone membrane matrix. The fluorine-free nanofilament coating effectively prevents membrane wetting under high hydrostatic pressure (>11.5 bar) without compromising vapor transport. With large inner micro-porous structures, the nanofilament-coated membrane improves the distillation flux by up to 60% over the widely used commercially available membranes, while showing excellent salt rejection and operating stability. Our approach will allow the fabrication of high-performance composite membranes with multi-scale porous structures that have wide-ranging applications beyond desalination, such as in cleaning wastewater. Membrane distillation is an emerging desalination technology to obtain freshwater from saline based on low-grade energy. Here the authors report on novel superhydrophobic hierarchical porous membranes with enhanced distillation flux suitable for desalination or wastewater treatment.

Two carbon composite materials were prepared by mixing avocado biochar and methyl polysiloxane (MK). Firstly, MK was dissolved in ethanol, and then the biochar was added at different times. In sample 1 (R1), the time of adding biochar was immediately after dissolving MK in ethanol, and in sample 2 (R 2 ), after 48 h of MK dissolved in ethanol. The samples were characterized by nitrogen adsorption/desorption measurements obtaining specific surface areas (S BET ) of 115 m2 g −1 (R 1 ) and 580 m2 g −1 (R 2 ). The adsorbents were further characterized using scanning electron microscopy, FTIR and Raman spectroscopy, adsorption of vapors of n-heptane and water, thermal analysis, Bohem titration, pHpzc, and C H N elemental analysis. R 1 and R 2 adsorbents were employed as adsorbents to remove the antibiotic ciprofloxacin from the waters. The t 1/2 and t 0.95 based on the interpolation of Avrami fractional-order were 20.52 and 246.4 min (R 1 ) and 14.00 and 157.6 min (R 2 ), respectively. Maximum adsorption capacities (Q max ) based on the Liu isotherm were 10.77 (R 1 ) and 63.80 mg g −1 (R 2 ) for ciprofloxacin. The thermodynamic studies showed a spontaneous and exothermic process for both samples, and the value of ΔH° is compatible with physical adsorption.

Silicone-rubber baby teats used to bottle-feed infants are frequently disinfected by moist heating. However, infant exposure to small microplastics (<10 μm) potentially released from the heated teats by hydrothermal decomposition has not been studied, owing to the limitations of conventional spectroscopy in visualizing microplastic formation and in characterizing the particles at the submicrometre scale. Here both the surfaces of silicone teats subjected to steam disinfection and the wash waters of the steamed teats were analysed using optical-photothermal infrared microspectroscopy. This new technique revealed submicrometre-resolved steam etching on and chemical modification of the teat surface. Numerous flake- or oil-film-shaped micro(nano)plastics (MNPs) (in the size range of 0.6–332 μm) presented in the wash waters, including cyclic and branched polysiloxanes or imides, which were generated by the steam-induced degradation of the base polydimethylsiloxane elastomer and the polyamide resin additive. The results indicated that by the age of one year, a baby could ingest >0.66 million elastomer-derived micro-sized plastics (MPs) (roughly 81% in 1.5–10 μm). Global MP emission from teat disinfection may be as high as 5.2 × 10 13 particles per year. Our findings highlight an entry route for surface-active silicone-rubber-derived MNPs into both the human body and the environment. The health and environmental risks of the particles are as yet unknown. Steam disinfection of silicone-rubber baby teats can lead to steam etching and chemical modification of the teat surface. This can release micro- and nanoplastics and result in ingestion. The results suggested that by the age of one year, a baby could ingest more than 600,000 microplastics.

This study focuses on the synthesis of hybrid luminescent polysiloxanes and silicone rubbers grafted by organometallic rhenium(I) complexes using Cu(I)-catalyzed azido-alkyne cycloaddition (CuAAC). The design of the rhenium(I) complexes includes using a diimine ligand to create an MLCT luminescent center and the introduction of a triple C≡C bond on the periphery of the ligand environment to provide click-reaction capability. Poly(3-azidopropylmethylsiloxane-co-dimethylsiloxane) (N3-PDMS) was synthesized for incorporation of azide function in polysiloxane chain. [Re(CO)3(MeCN)(5-(4-ethynylphenyl)-2,2′-bipyridine)]OTf (Re1) luminescent complex was used to prepare a luminescent copolymer with N3-PDMS (Re1-PDMS), while [Re(CO)3Cl(5,5′-diethynyl-2,2′-bipyridine)] (Re2) was used as a luminescent cross-linking agent of N3-PDMS to obtain luminescent silicone rubber (Re2-PDMS). The examination of photophysical properties of the hybrid polymer materials obtained show that emission profile of Re(I) moiety remains unchanged and metallocenter allows to control the creation of polysiloxane-based materials with specified properties.

This investigation of hydroxyl and polysiloxane absorption peaks in elastic polymer composites reveals significant spectral shifts within the fingerprint region of FTIR spectra. Using poly(vinyl butyral) (PVB) as the base polymer and poly(vinyl acetate) (PVAc) and poly(vinyl alcohol) (PVA) as reference materials, solvent effects on polymer–solvent interactions were systematically analyzed. Among the tested alcohol solvents, PEG 400 induced the most pronounced spectral changes, with the C=O stretching band shifting from 1740 to 1732 cm−1 and the O–H band significantly broadening and downshifting to around 3300 cm−1, reflecting strong hydrogen-bonding interactions. Wavelet-based noise reduction effectively enhanced the signal-to-noise ratio, reducing the baseline standard deviation by over 90%. This study introduces a novel noise-enhanced FTIR recognition model that integrates baseline noise metrics to improve detection sensitivity. The model successfully uncovers subtle structural variations in polymer–solvent systems that are typically masked by conventional FTIR techniques, advancing materials analysis and providing a robust framework for future FTIR-based diagnostics and material characterization.