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Bio-inspired by spider silk, we simultaneously integrated high strength and toughness to PVA/TA films via extensive hydrogen bonding interactions.

China has a large area of inland salinealkali land, equivalent to 40% of the total cultivated land in the country. The principal features of these lands are high salt content, high pH, and poor soil structure with low water infiltration and poor drainage. These conditions effectively prevent the exploitation of such land for agriculture.

N,N-Diethyl-m-toluamide has been widely used in the mosquito-repellent finishing of textiles over the past few decades, but the use of N,N-diethyl-m-toluamide as a dye carrier for aramid dyeing with disperse dye has been seldom reported. Meanwhile, the application of aramid fibre in clothing is limited because it is difficult to dye. In this work, the effect of N,N-diethyl-m-toluamide on the dyeing properties of aramid fibre was examined by measuring the percentage disperse dye exhaustion under different conditions. In order to understand the mechanism by which N,N-diethyl-m-toluamide promotes the exhaustion of disperse dye on aramid fibre, the ultraviolet-visible spectrum of the dye and N,N-diethyl-m-toluamide solution, the glass transition temperature, the crystalline structure, and the degree of orientation of aramid fibre treated with N,N-diethyl-m-toluamide were measured by ultraviolet-visible spectrophotometry, differential scanning calorimetry, X-ray diffraction analysis, and velocity-oriented tests respectively. The results indicated that N,N-diethyl-m-toluamide not only could reduce the glass transition temperature and degree of orientation of aramid fibre but could also improve the solubility of disperse dye in aqueous solution, and therefore could enhance the percentage disperse dye uptake on aramid fibre, whereas treatment with N,N-diethyl-m-toluamide showed little effect on the crystalline structure of aramid fibre. The results implied that N,N-diethyl-m-toluamide was beneficial to the diffusion of disperse dye molecules into the amorphous region of aramid fibre under the dyeing conditions, but seldom affected the mechanical properties of aramid fibre.

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Adsorption thermodynamic and kinetic study of disperse dye on cotton fiber modified with tolylene diisocyanate derivative was carried out under the condition of pH value 6.0 ± 0.2, initial dye concentration 0.01-3.0 g/L and liquor ratio 2,000:1. The result showed the equilibrium adsorption isotherm of disperse dye on modified cotton fiber was Langmuir-Nernst mixed Model and the saturated adsorption capacity of the turning point was 7.1429 mg/g. The calculation of the thermodynamic parameters indicated that the Van der Waals' forces played a major role between the disperse dye and the modified cotton fiber, and the adsorption of disperse dye on the modified cotton fiber was exothermic process. Compared with the diffusion coefficient and the activation energy of disperse dye on various fibers, the disperse dye diffusion in modified cotton fiber was more difficult than that in original cotton. Meanwhile, it was found that the adsorption kinetics of disperse dye on modified cotton fiber was well agreed with a pseudo second-order kinetic model.

Solvothermal reactions of zinc and cadmium nitrates with 1,3,5-tri-4-pyridyl-1,2-ethenylbenzene (tpeb) in the presence of various carboxylic acids including 4-iodobenzoic acid (4-HIBA), benzene-1,4-dicarboxylic acid (1,4-H2BDC), 2,5-furan­dicarboxylic acid (2,5-H2FDC), 2,5-dibromo­terephthalic acid (2,5-H2DB­TPA), 1,2-cyclohexane­dicarboxylic acid (1,2-H2CHDC), and 1,5-pentanedioic acid (1,5-H2PDC) gave rise to eight coordination complexes, viz, [Zn­(tpeb)2­(4-IBA)2]·2H2O (1), {[Cd­(NO3)­(tpeb)­(4-IBA)]·H2O} n (2), {[Cd2­(NO3)2­(tpeb)2­(1,4-BDC)]} n (3), {[Cd2­(tpeb)2­(2,5-FDC)2]·2H2O} n (4), [Cd­(tpeb)­(2,5-DBTPA)2] n (5), {[Cd2­(H2O)2­(tpeb)2­(1,2-CHDC)2]·H2O} n (6), [Zn­(tpeb)­(1,2-CHDC)] n (7), and {[Zn­(tpeb)­(1,5-PDC)]·H2O} n (8). Compound 1 is a discrete mononuclear complex with its Zn­(II) center coordinated by two pairs of tpeb and 4-IBA ligands. Compound 2 has a 2D waterfall-like network constructed from bridging [Cd­(NO3)­(4-IBA)] units with tpeb ligands. Compounds 3, 4, and 5 contain similar 1D [Cd­(tpeb)] n chains, which are linked by 1,4-BDC, 2,5-FDC, and 2,5-DBTPA bridges, respectively, forming either 2D (2 and 3) networks or a 3D (4) framework. Compound 6 holds a 2D wavelike layer structure in which dimeric [Cd2­(H2O)2­(1,2-CHDC)2] fragments are connected by two couples of tpeb ligands. Compounds 7 and 8 contain similar 2D fish-scale networks assembled from 1D chains of [Zn­(1,2-CHDC)] n or [Zn­(1,5-PDC)] n bridged by tpeb ligands. Compound 6, as a representative sample, has larger absorption in the visible light region, and can be employed to efficiently degrade Congo red in water without additional oxidizing or reducing reagents upon visible light irradiation. This photocatalyst could be recycled at least five times without evident loss of its catalytic efficiency.

In this study, the effects of polycarboxylic acid sodium salt on the dyeing of cotton with reactive dyes were evaluated by measuring and comparing the K/S values and dyeing fastnesses of the dyed cotton fabric samples. Results showed that the K/S value and dyeing fastness of cotton fabrics dyed with polycarboxylic acid sodium salt, substituting inorganic salts as exhausting agent were close to that of with sodium chloride when dip-dyeing process was used. While, in pad-dry dyeing, the K/S value of cotton fabric samples dyed with polyacid salts as exhausting agent was higher than that of with sodium sulfate, and the dyeing fastnesses of these samples were nearly the same. The dyeing mechanism of cotton fabric with reactive dye, using polycarboxylic acid sodium salt as exhausting agent was analyzed. The dyeing exhausting mechanism of reactive dye seems different when the inorganic salt and polycarboxylic acid sodium salt were used as exhausting agent in the dyeing of cotton fabric with reactive dye. The polycarboxylic acid sodium salt, as weak electrolyte, increased the dyeuptake of reactive dye on cotton fabric not only by screening negative charges on cotton surface, but also by the effect of salting-out or hydrophobic combination.