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The effect of solvent on the polymerization of 3 ‐ hexylthiophene with FeCl3 was evaluated using time ‐ dependent partial fluorescence yield X ‐ ray absorption fine structure measurements. FeCl3 acts as a catalyst when the reaction is performed in CHCl3, whereas it behaves as an oxidant in hexane. [ABSTRACT FROM AUTHOR]

Well-defined poly(methacrylate)swith liquid crystal side chains,designated as PPHM, were synthesized by a living anionic polymerizationmethod. Introducing a short-length alkyl chain at the end of the sidechain, the solubility of the polymer was improved, resulting in highermolecular weight polymers. While the highest weight-average molecularweight (Mw) of PPHM was 68k, it exceeded100k for a slight-polydisperse PPHM. Wide-angle X-ray diffraction(WAXD) revealed that PPHM formed a smectic A phase with 2.7 nm layerspacing and that the layer structure is present even in the glassystate at room temperature. Molecular aggregation states of PPHM insurface regions of films were characterized by sum-frequency generation,grazing-incidence WAXD, and contact angle measurements. The resultsshow that the PPHM with a larger Mwformeda layer structure parallel to the film plane. Although low MwPPHM also maintained a layer structure, thestructure became more random within internal regions. The surfacereorganization of PPHM with larger Mwwassuppressed in comparison with smaller ones. [ABSTRACT FROM AUTHOR]

Fabrics consisting of cotton‐core/polypyrrole (PPy)‐sheath fibers (cotton/PPy fabrics) are synthesized by aqueous chemical oxidative seeded polymerization of pyrrole and are utilized as a solar evaporation device. Scanning electron microscopy studies and elemental microanalyses reveal the thickness of the PPy sheath increases from a few tens nm to ≈200 nm with an increase of pyrrole monomer concentration in the polymerization system. The temperature of cotton/PPy fabrics increases upon irradiation with artificial sunlight to ≈33–45 °C in the dry state, due to light‐to‐heat photothermal conversion by the PPy component. Thanks to the photothermal property of the fabrics, water impregnated within the cotton/PPy fabrics can evaporate efficiently under the irradiation of artificial sunlight. Light‐induced water evaporation experiment using an artificial seawater confirms that ionic concentrations drastically decreases, indicating successful desalination. [ABSTRACT FROM AUTHOR]

In recent years, fatty acids have garnered significant attention as a natural phase‐change material and a hydrophobizer due to their biocompatibility and biodegradability. In this study, the utilization of fatty acid is proposed as a polymerization medium for the first time. As a specific reaction, chemical oxidative polymerizations of pyrrole is conducted using ferric chloride as an oxidant in a stearic acid medium. The polymerizations resulted in the production of micrometer‐sized polypyrrole (PPy) grains, which are aggregates of atypical primary particles with submicrometer size. The PPy grains are doped with stearic acid, suggesting that the stearic acid functioned as a dopant and a hydrophobizing agent as well as a polymerization medium. The dried PPy grains can adsorb at the air–water interface and function as a liquid marble stabilizer with light‐to‐heat photothermal properties. The liquid marble can move on a planar air‐water interface by Marangoni flow induced by NIR laser light irradiation. [ABSTRACT FROM AUTHOR]

A suitable silane coupling agent (SCA) structure to improve the water absorption and mechanical strength of silica particle‐filled epoxy resin was investigated. Bonding, hydrocarbon, and fluorocarbon type SCAs were employed. The bonding type has glycidoxy or amino groups that react with epoxy resin, whereas the other types have only hydrophobic chains. The spherical silica particles were added to epoxy resin at amounts from 10 to 50 wt %. The effect of water absorption was consequently lowered in the order of hydrocarbon > bonding types. The fluorocarbon type SCA was also effective at zero and low silica content. Modification of the epoxy phase by SCA addition was clarified to have a more dominant effect than the adhesion of silica/epoxy interface for the lowering of water absorption, whereas it had been conventionally considered that interfacial adhesion had a more dominant effect. The mechanical strength was higher for the bonding type than the other type. Two addition methods were compared, a pretreatment method and an integral blend method in which all components were mixed simultaneously. The integral blend method was determined to be superior to the pretreatment method for both water absorption and mechanical strength, which was also contrary to the conventional view. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48615. [ABSTRACT FROM AUTHOR]

Poly(amic ‍acid) ‍nanoparticles ‍prepared ‍by ‍‍precipitation ‍polymerization with a dispersant were evaluated by small-angle X-ray scattering (SAXS) and field-emission scanning electron microscopy (FE-SEM). The particle size evaluation of poly(amic acid) nanoparticles in the liquid phase by SAXS was performed to gain insight into the size control of poly(amic acid) nanoparticles, and showed good agreement with visual observation by FE-SEM, explaining the effect of the dispersant in obtaining polyimide nanoparticles with small particle size. This indicates that the particle size is maintained without change during the solvent evaporation process. The polyamide nanoparticles controlled by the dispersant effect maintained their size after imidization, and polyimide nanoparticles with a minimum radius of about 60 nm were prepared., Competing Interests: We declare we have no competing interests., (© 2024 The Authors.)

An organometallic nickel complex containing thieno[3,2- b ]thiophene units was designed and synthesized. Composite films of the resulting nickel complex and polyvinylidene difluoride, which can be fabricated via a simple solution process under atmospheric conditions, exhibit remarkably high n-type conductivity (>200 S cm -1 ). Moreover, the thermoelectric power factor of the n-type composite film was proven to be air stable. A grazing-incidence wide-angle X-ray diffraction analysis indicated a significant impact of introducing the thieno[3,2- b ]thiophene core into the backbone of the nickel complex on the orientation within the composite films.

A contracted doubly N-confused dioxohexaphyrin(1.1.1.1.1.0) complex consisting of two paramagnetic copper metals and open-shell π-radical ligand was synthesized as a new multi-heterospin motif. X-ray spectroscopy supported the divalent character of the inner copper centers, and electron paramagnetic resonance and magnetometric studies suggested the presence of unpaired d electrons strongly antiferromagnetically coupled with π-radicals delocalized on the macrocycle. The 25 π non-innocent dioxohexaphyrin ligand allowed the facile interconversion between antiaromatic 24 π and aromatic 26 π species, respectively, upon redox reactions., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)