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1.
Polyacrylamide/sodium alginate modified montmorillonite (PAM/SA‐MMT) superabsorbent composites were synthesized by free‐radical polymerization under normal atmospheric conditions. They were characterized by X‐ray diffraction, scanning electron microscopy, and Fourier transform infrared spectroscopy (FTIR). Their water absorbency and methylene blue (MB) adsorption behaviors were studied. Compared with PAM/MMT composites, PAM/SA‐MMT composites demonstrated greater water absorbency (863 g g?1 in distilled water and 101 g g?1 in 0.9 wt % NaCl solution) and higher adsorption capacity of 2639 mg g?1 for MB. The adsorption behaviors of the composites showed that the isotherms and adsorption kinetics were in good agreement with the Langmuir equation and pseudo‐second‐order equation, respectively. FTIR analysis suggested that the MB adsorption of PAM/SA‐MMT composites via a mechanism combined electrostatic, H‐bonding and hydrophobic interaction. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014 , 131, 40013.  相似文献   

2.
In this article, the multiple stimulus‐responsive organic/inorganic hybrid hydrogels by combining poly(2‐(2‐methoxyethoxy) ethyl methacrylate‐co‐oligo (ethylene glycol) methacrylate‐co‐acrylic acid) (PMOA) hydrogel with magnetic attapulgite/Fe3O4 (AT‐Fe3O4) nanoparticles were applied to the removal of Rhodamine B (RhB) dye from wastewater. The adsorption of RhB by the hydrogels was carried out under different external environmental, such as pH, temperature and magnetic‐field. The results showed that the hydrogels still possessed temperature, pH and magnetic‐field sensitivity during the adsorption process, which indicated that the adsorption could be controlled by the hydrogels responsive. The dye adsorption had a significant increment at 30°C and the removal of RhB could reach to over 95%. Besides, the low pH values were also favorable for the RhB adsorption, the removal was over 90% at pH = 4.56. Kinetic studies showed that the pseudo‐second order kinetic model well fitted the experimental data. The rate constant of adsorption was 0.0379 g/mg min. Langmuir and Freundlich isotherm models were applied to the equilibrium adsorption for describing the interaction between sorbent and adsorbate. The maximum KL and KF were 2.23 (L/g) and 0.87 (mg/g) at 30°C, respectively. Under the external magnetic‐field, the adsorption rate significantly increased within 250 min and the hydrogels could be separated easily from wastewater. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42244.  相似文献   

3.
In this study, a type of polymeric fluorescence brightener (PFB) with a triazine–stilbene structure was synthesized through a three‐step condensation reaction, and the performance of this PFB on antiyellowing was also investigated by the whiteness of paper coated with the as‐prepared PFB. Fourier transform infrared spectra revealed that the chlorine atom (·Cl) was substituted by a poly(vinyl alcohol) (PVA) group ([CH2CHOH]n). According to the UV aging experiment, the PFB not only enhanced the whiteness of the paper but also improved the anti‐UV aging properties [compared to those of VBL 4′‐double‐(6‐diethanolamine‐4‐sulfanilic acid‐1,3,5‐triazine‐2‐amino)‐stilbene‐2,2′‐disulfonic acid sodium, a type of commonly used fluorescent whitening agent as a light stabilizer and fluorescent brightening agent]. Moreover, the results of UV–visible spectra indicated that the substitution of PVA suppressed the isomerization of trans conformers to cis conformers under UV light irradiation; this was attributed to the big space steric hindrance of PVA in the as‐prepared samples being restricted the isomerization reaction. Meanwhile, the solubility of the as‐prepared sample was also improved because more hydroxyl groups were introduced into the PFB with the substitution of PVA. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45536.  相似文献   

4.
A new series of Y‐type polyurethanes containing different concentrations of nonlinear optical (NLO) chromophore with aniline donor and tricyanofurane (TCF) acceptor have been successfully prepared, and characterized by FTIR, UV‐Vis, and 1H‐NMR spectra. New polyurethanes were synthesized with different chromophore contents by introducing diol N, N‐dihydroxyethylaniline or 4‐[N, N‐(dihydroxyethyl)amino]benzaldehyde. These NLO polyurethanes exhibit good film forming property and high thermal stability up to 281°C. The highest electro‐optic coefficient (r33) of polymers is up to 39 pm V?1 measured by simple reflection technique at 1310 nm, and the temporal stability of the poling‐induced order at elevated temperature of 80°C was much improved through the introducing of hydrogen bonding interaction in this system. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

5.
A cationic hydrogel synthesized from (3‐acrylamidopropyl) trimethyl ammonium chloride as poly[(3‐acrylamidopropyl) trimethyl ammonium chloride] [p(APTMACl)] was put into contact with the chloride salts of metals such as CoCl2, NiCl2, and CuCl2 in ethanol. The metal‐loaded p(APTMACl) hydrogels were used as catalyst systems in hydrogen generation from the hydrolysis of sodium borohydride (NaBH4) and ammonia borane. The activation energy values for the hydrolysis reaction were calculated for all of the catalyst systems and were found to be 53.43 and 26.74 kJ/mol for p(APTMACl)–[CoCl4]2? and p(APTMACl)–[NiCl4]2?, respectively. These activation parameters were better than values reported in the literature for the ionic liquid metal complexes of smaller molecules used for the same purpose. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40183.  相似文献   

6.
Copper phthalocyanine blue was encapsulated with a copolymer of styrene and maleic acid (PSMA) via a phase‐separation technique, and a PSMA‐encapsulated pigment dispersion was prepared. The effects of the additive on the stability of the dispersion were studied. Scanning electron microscopy photographs revealed that the particles in the PSMA‐encapsulated pigment dispersion were more uniform than those in a PSMA‐dispersed pigment dispersion. X‐ray photoelectron spectroscopy provided evidence that the PSMA‐encapsulated pigment acquired abundant carboxylic groups that could improve its wettability to water. Moreover, the results also indicated that the PSMA‐encapsulated pigment dispersion had improved color strength, its stability could be greatly influenced by the pH value and ion strength, and its apparent viscosity changed little with an increase in the shear rate. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

7.
An organic‐solvent‐soluble disperse dye was introduced into an aqueous phase by a reaction with a self‐emulsified, aqueous‐based polyurethane (PU), and this resulted in the formation of a homogeneous, aqueous polymeric dye dispersion. This aqueous polymeric dye was stable in a water phase with excellent color extension upon application. It was formulated with a latent curing agent, polyaziridine (e.g., TMPTA‐AZ), as a single‐component, self‐curable, aqueous polymeric dye. The curing reaction took place between PU carboxylic acid and the latent curing agent upon drying. A self‐cured polymeric dye was obtained with excellent color extension and fastness and resistance to organic solvents and water after drying. This single‐component, self‐curable, aqueous‐based PU system containing a dye has potential for printing, writing, and dyeing applications. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 2006 © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3741–3747, 2006  相似文献   

8.
Glutathione (GSH) is one of major antioxidants inside cells that regulates oxidoreduction homeostasis. Recently, there have been extensive efforts to visualize GSH in live cells, but most of the probes available today are simple detection sensors and do not provide details of cellular localization. A new fluorescent probe (pcBD2‐Cl), which is cell permeable and selectively reacts with GSH in situ, has been developed. The in situ GSH‐labeled probe (pcBD2–GSH) exhibited quenches fluorescence, but subsequent binding to cellular abundant glutathione S‐transferase (GST) recovers the fluorescence intensity, which makes it possible to image the GSH–GST complex in live cells. Interactions between probe and GST were confirmed by means of photo‐crosslinking under intact live‐cell conditions. Interestingly, isomers of chloro‐functionalized 4,4‐difluoro‐4‐bora‐3a,4a‐diaza‐s‐indacene (BODIPY) compounds behaved very distinctively inside the cells. Following co‐staining imaging with MitoTracker and mitochondria fractionation upon lipopolysaccharide‐mediated reactive oxygen species induction experiments showed that pcBD2–GSH accumulated in mitochondria. This is the first example of a live‐cell imaging probe to visualize translocation of GSH from the cytosol to mitochondria.  相似文献   

9.
To realize the low‐temperature dyeing of wool fibers, the use of auxiliaries and wool modification are common methods. Low‐temperature auxiliaries may cause water‐pollution problems, and wool modification is a costly and uncontrollable process. In this study, new acid dyes, named D1–D3, containing polyetheramine groups were synthesized and applied to wool fiber by conventional and low‐temperature exhaust dyeing procedures. The results indicate that the new acid dyes could interact with wool‐fiber‐like auxiliaries and render a high exhaustion rate to the wool fiber at a dyeing temperature of 80 °C. In comparison with Acid Blue 25, the D1–D3 dyes showed an increased dyeing rate, especially under a dyeing temperature of 80 °C. Despite the bigger relative molecular masses of D1–D3, the exhaustion rates of D1–D3 were still higher, and the times of half‐dyeing were shorter than that of Acid Blue 25. The color differences between the wool fabrics dyed with the four dyes at 80 and 98 °C, respectively, were compared. We found that the color differences of D1–D3 between 80 and 98 °C were smaller than that of Acid Blue 25. The interactions between the dyes and wool fiber were analyzed and manifested by the measurement of the ζ potential of the dyes and wool fiber. The leveling and transfer properties of the D1–D3 dyes were also investigated, and the color differences of the wool fabrics dyed with Acid Blue 25, D1, and D2 were very low at all measured pH values and temperatures. The fastnesses of D1–D3 on wool fabric were almost the same as that of Acid Blue 25. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45793.  相似文献   

10.
In this research, we aimed to apply color‐matching, double‐shelled microcapsules to deal with outdoor‐clothing sunscreen‐indicator identifications on cotton fabrics with a covalent‐bonding coating method; this method allows one to display both the UV intensity and a warning. The color‐property characteristics of color‐matching‐double‐shelled‐photochromic‐microcapsule–treated patterns on cotton fabrics under various sunshine irradiation intensities are very close to those of inkjet‐printing color‐gradation patterns, which indicate sunshine irradiation intensities. Color‐matching, double‐shelled microcapsules were obtained by the addition of red double‐shelled microcapsules into yellow double‐shelled microcapsules. We increased the weight ratio of the red microcapsules and added blue double‐shelled microcapsules into the red double‐shelled microcapsules when the weight ratio of blue microcapsules was increased. Color‐matching, double‐shelled photochromic microcapsules, whose yellow/red/blue weight ratios were 5.6/0/0, 4.8/0.8/0, 2.4/3.2/0, and 0.8/4.8/0–0/0/5.6, presented distinct color‐property characteristic changes under various irradiation intensities and presented a good color identification; a rather dark, bright color; and good laundering durability of covalent bonding on cotton fabrics. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44698.  相似文献   

11.
In this study, a novel kind of hybrid pigment based on nanoclays and dyes was synthesized and characterized. These nanoclay‐based pigments (NCPs) were prepared at the laboratory with sodium montmorillonite nanoclay (NC) and methylene blue (MB). The cation‐exchange capacity of NC exchanged with MB was varied to obtain a wide color gamut. The synthesized nanopigments were thoroughly characterized. The NCPs were melt‐mixed with linear low‐density polyethylene (PE) with an internal mixer. Furthermore, samples with conventional colorants were prepared in the same way. Then, the properties (mechanical, thermal, and colorimetric) of the mixtures were assessed. The PE–NCP samples developed better color properties than those containing conventional colorants and used as references, and their other properties were maintained or improved, even at lower contents of dye compared to that with the conventional colorants. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

12.
13.
A series of nanocomposite hydrogels were prepared from various ratios of N‐isopropylacrylamide (NIPAAm) and organic montmorillonite (MMT). The influence of the extent of MMT in the NIPAAm/MMT nanocomposite hydrogels on the physical properties and drug‐release behavior was the main purpose of this study. The microstructure and morphology were identified by X‐ray diffraction (XRD) and scanning electronic microscopy (SEM). The results showed that the swelling ratios for these nanocomposite hydrogels decreased with increase in the content of MMT. The gel strength and Young's modulus of the gels also increased with increase in the content of MMT. XRD results indicated that the exfoliation of MMT was achieved in the swollen state. Finally, the drug‐release behavior for the gels was also assessed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3652–3660, 2003  相似文献   

14.
A new type of proton‐exchange membrane based on poly(vinyl alcohol) (PVA) modified KE reactive dyes (KE‐4BD) was prepared and evaluated as H+‐conducting polymer electrolytes. The effects of the content of KE‐4BD on the membrane H+ conductivity and water uptake were studied with an alternating‐current impedance technique and the method of weighing, respectively. Fourier transform infrared and scanning electron microscopy were used for the chemical and structural characterization of these membranes. With all of these properties, the optimal mass ratio between PVA and KE‐4BD was 1:0.5, and the resulting membrane exhibited a high proton conductivity (0.109 S/cm) at room temperature; this afforded a power density of 83.9 mW/cm2 at 210.4 mA/cm2 and an open‐circuit voltage of 810.8 mV. The PVA/KE‐4BD membranes showed a high oxidative stability in Fenton's reagent (3% H2O2 v/v, 2 ppm FeSO4). Thermal analysis also showed that the membranes exhibited a significant improvement in thermal stability. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43019.  相似文献   

15.
To improve the dyeing properties of ramie, the ecofriendly organic solvent N‐methylmorpholine‐N‐oxide (NMMO) was used to substitute sodium hydroxide as a ramie‐fiber swelling solvent. Through padding and baking pretreatment, ramie fabric was modified by an NMMO aqueous solution. Ultraviolet–visible spectrophotometry, Fourier transform infrared spectroscopy, X‐ray diffraction, and differential scanning calorimetry were used to investigate the effects of NMMO pretreatment on the structure of the ramie, whereas the color strength (K/S, where K is the light absorption coefficient and S is the scattering coefficient), adsorption isotherm, and dye uptake rate curve were measured to investigate the effects of NMMO pretreatment on the dyeing properties of the ramie. The results show that the ramie fiber experienced a limited and irreversible swelling because of the partial breakage of interhydrogen and intrahydrogen bonds of cellulose molecules in the amorphous area, but the crystal and chemical structure of the ramie fiber did not change obviously under the experimental conditions. The K/S value of the NMMO‐modified ramie fabrics dyed with reactive dyes increased by about 100%, and the dye uptake increased by 27.88% compared to that of the raw sample, whereas the standard affinity and diffusion coefficient value of the reactive dyes on the NMMO‐modified ramie fabric were higher than those of the raw ramie fabric. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

16.
Two series of anionic water‐borne polyurethanes with alkali resistance and covalent bonds of a reactive dye were synthesized with different molar ratios of poly(tetramethylene glycol) (PTMG). They were classified with respect to PTMG 1000 and PTMG 2000. The fiber blends of polyester/nylon nonwoven fabrics were dipped into silicon‐containing, water‐borne polyurethane and squeezed to an 80% pickup ratio. Finally, the manmade leather was treated with alkali reduction and dyed with a reactive dye. The alkali reduction and the thermal, mechanical, and dyeing properties of the manmade leather were studied. For alkali reduction, different ratios of NaOH and Na2CO3 concentrations were used. Na2CO3 was used because of its better spreading and buffering properties. The softness and breaking load were measured and related to the weight reduction. For the dyeing properties, a reactive dye with vinyl sulfone groups was found to bond with the OH group of water‐borne polyurethane by covalent bonding. On the basis of alkali reduction, a mixture of NaOH and Na2CO3 with a concentration ratio of 0.1N/0.2N could lead to better softness and alkali reduction of leather. For the mechanical properties, leather of the PTMG 1000 series showed a higher breaking load than leather of the PTMG 2000 series. However, less elongation in the PTMG 1000 series resulted. Differential scanning calorimetry showed an endothermic peak at 50–100°C. This indicated that the glass‐transition temperature of the hard segment decreased with an increasing amount of the soft segment in leather; meanwhile, both the glass‐transition temperature of the soft segment and the melting temperature of the hard segment also decreased as the content of the soft segment increased. For the dyeing properties, the reactive blue dye could reach up to 96.1% dye uptake in the polyurethane part of the leather. Moreover, the washing fastness could be graded as high as 4–5, and the light resistance was also graded to 4–5, in the dyed leather. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 2324–2335, 2005  相似文献   

17.
In this scientific work, a novel class of antimicrobial nanocomposite hydrogels were designed and synthesized by chemical and environmentally bioprocess using Kolliphor, acrylamide, and mint leafs in order to achieve antiseptic property for wound applications. In the bioprocess approach, silver nitrate and gold chloride were nucleated with mint leafs in order to obtain effective free individual nano‐inorganic compounds to provide superior antibacterial assets. The formations of dual inorganic nanoparticles were confirmed by transmission electron microscopy, which indicated the size of nanoparticles in the range of approximately 3 ± 2 nm and without agglomeration. The formations of biomaterials were characterized using Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopic–energy dispersive spectrometric studies and their swelling properties were determined. Furthermore, the pure hydrogel and the dual inorganic nanocomposite hydrogels developed were tested for antibacterial activities. When compared with the neat hydrogel, the nanocomposite hydrogels significantly improved their anti‐bacterial activities on Bacillus bacterium. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42781.  相似文献   

18.
Herein, we report the preparation of robust polyacrylic acid hydrogel using rod‐like amidodiol as physical crosslinker. Polyacrylic acid–amidodiol hydrogels were characterized for its chemical structure, rheology, swelling, diffusion, and adsorption properties. Kinetics and mechanism of adsorption were investigated by UV–visible spectroscopy using dyes such as rhodamine 6G and methylene blue as adsorbate. Results suggested pseudo second‐order kinetics of multilayer adsorption and hydrogel could retain its shape even after swelling. Effect of amidodiol on the adsorption of dyes was investigated. Extent of interaction between adsorbate–adsorbate and adsorbent–adsorbate was studied using Gile's model. The generated results may provide a low cost simple technology for developing robust polymeric hydrogel adsorbent. The adsorption characteristics results can be exploited for setting up pilot plant adsorbent for the removal of such organic toxic materials. Finally, we have demonstrated its application for the removal of dyes from waste water collected from textile and paper industries. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40908.  相似文献   

19.
A dioxazine‐based color pigment was added to a commercial polyamide 6 (PA6) through an extrusion process, in order to prepare monoconcentrated violet masterbatches through different production set‐up. A detailed characterization of the resulting materials was carried out in order to find the best processing parameters combination to optimize pigment dispersion and to reduce the clogging power. The preparation of masterbatches with repeated extrusions markedly reduced the filter pressure value and increased the Relative Color Strength, while filtration did not significantly influence pigment dispersion. Rheological measurements and end‐groups analysis were conducted on the same materials with the aim to evaluate their thermal degradation resistance, and the thermal stability of the compounds was retained even upon three extrusions. Therefore, it can be concluded that a proper optimization of the process parameters could lead to an important reduction of the production waste, increasing the quality of the final product. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41452.  相似文献   

20.
In this study, nonaqueous emulsion solvent evaporation was utilized to prepare nonaqueous dispersions derived from various methanol‐soluble polymers, such as polyvinylpyrrolidone (PVP), polyethylene glycol, polyvinyl acetate (PVAC), and poly(acrylic acid), using a block–random copolymer surfactant; the block–random copolymer poly(SMA)88b‐poly(DEAGMA15r‐SMA14), composed of stearyl methacrylate, and diethanolamine‐modified glycidyl methacrylate, was used to stabilize the nonaqueous emulsions of methanol containing the polymers and an isoparaffin solvent, Isopar M. In the cases without dye, all emulsions and dispersions obtained after the evaporation of methanol exhibited nanometer‐sized particles as well as good stability. For emulsions consisting of dye‐containing methanol phases, particle sizes and stability of the obtained dispersions were dependent on the nature of the methanol‐soluble polymers. The dispersions derived from PVP and PVAC, which possibly interact weakly with the block–random copolymer and dye, exhibited good stability and a small particle size, which can be applied for inkjet printing. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44671.  相似文献   

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