In this paper, diffuse coplanar surface barrier discharge plasma at atmospheric pressure has been used for surface modification of polyester/cotton (PESc) fabric, which was subsequently modified by ...sol-gel process using suitable organofunctional silanes to enhance its hydrophobicity. Modified PESc fabric surfaces were conditioned during the gelling process to obtain the permanent hydrophobicity. The contact angle of water before washing of plasma and sol-gel pretreated PESc fabric was found to be 154° and 151° after standardized washings. It was also demonstrated that the process is applicable at the industrial scale.
The epoxy nanocomposites filled with 0.1, 0.5, and 1 wt% nanodiamonds (nanoD) were prepared and their properties were compared with neat epoxy network or epoxy nanocomposite filled with 1 wt% ...multiwalled carbon nanotubes (MWCNTs). The obtained nanoD-epoxy composites increased significantly thermal stability of prepared nanocomposites in comparison with neat epoxy matrix. The exponential decay of light transmittance with increasing concentration of nanoD in sample was observed. The values of storage modulus G` and glass transition temperature Tg significantly decreased by addition of nanoD to epoxy network. This is caused by inhibition of cross-linking reaction of epoxy- and amino- groups by nanoD.
Modification of polymer blends with nanofillers is an efficient way to improve material parameters. This work deals with application of neat and stearylamine-modified graphene oxide in the polyamide ...6/elastomer system using different mixing protocols. Combination of ethene-propene elastomer and graphene oxide leads to a polyamide material with increased strength, stiffness, and toughness. The reason is synergistic effect of the core-shell structure (nanofiller localized at interface) on mechanical properties. The structure-directing effect of graphene oxide is comparable with that of nanoclay. The mechanism of affecting dynamic phase behavior is different as a consequence of graphene oxide nature and interactions with polymer components.
Indian spice curcumin is known for its anticancer properties, but the anticancer mechanisms of nanoparticulate curcumin have not been completely elucidated. We here investigated the
in vitro
...anticancer effect of blue light (470 nm, 1 W)-irradiated curcumin nanoparticles prepared by tetrahydrofuran/water solvent exchange, using U251 glioma, B16 melanoma, and H460 lung cancer cells as targets. The size of curcumin nanocrystals was approximately 250 nm, while photoexcitation induced their oxidation and partial agglomeration. Although cell membrane in the absence of light was almost impermeable to curcumin nanoparticles, photoexcitation stimulated their internalization. While irradiation with blue light (1–8 min) or nanocurcumin (1.25–10 μg/ml) alone was only marginally toxic to tumor cells, photoexcited nanocurcumin displayed a significant cytotoxicity depending both on the irradiation time and nanocurcumin concentration. Photoexcited nanocurcumin induced phosphorylation of c-Jun N-terminal kinase (JNK), mitochondrial depolarization, caspase-3 activation, and cleavage of poly (ADP-ribose) polymerase, indicating apoptotic cell death. Accordingly, pharmacologial inhibition of JNK and caspase activity rescued cancer cells from photoexcited nanocurcumin. On the other hand, antioxidant treatment did not reduce photocytotoxicity of nanocurcumin, arguing against the involvement of oxidative stress. By demonstrating the ability of photoexcited nanocurcumin to induce oxidative-stress independent, JNK- and caspase-dependent apoptosis, our results support its further investigation in cancer therapy.
This paper addresses the preparation of electrically conductive electrospun mats on a base of styrene-isoprene-styrene copolymer (SIS) and multiwall carbon nanotubes (CNTs) and their application as ...active sensing elements for the detection of vegetable oil impurities dispersed within water. The most uniform mats without beads were prepared using tetrahydrofuran (THF)/dimethyl formamide (DMF) 80:20 (v/v) as the solvent and 13 wt.% of SIS. The CNT content was 10 wt.%, which had the most pronounced changes in electrical resistivity upon sorption of the oil component. The sensors were prepared by deposition of the SIS/CNT layer onto gold electrodes through electrospinning and applied for sensing of oil dispersed in water for 50, 100, and 1000 ppm.
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