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Short and medium alkyd resins were modified using perfluorinated urethane toluene isocyanate (PFUTI). The modified resins were incorporated in a set of paint formulations containing different ratios of zinc phosphate as an inhibitive pigment. Promising results were achieved and corrosion protective properties were illustrated in various paint formulations and also in a paint formulation free of the inhibitive pigment. The corrosion protection efficiencies were enhanced by the improvement in the hydrophobicity of alkyd resin modified with perfluorinated toluene isocyanate (PFUTI). These results encourage us to minimize or neglect the most expensive inhibitive pigments from the economic point of view.

The purpose of this paper is to show how to remove some dyestuffs, as pollutants, from their aqueous solutions.

To achieve the goal, a water soluble hyperbranched poly (ester‐amide) (HBP) was synthesised using the melt polycondensation method by the reaction of maleic anhydride (MA) and diisopropanol amine (DIPA) at 140°C at a molar ratio of 1:1.3 MA: DIPA, respectively. This HBP was incorporated in the preparation of an effective microcrystalline cellulose (MCC)/dimethyloldihydroxyethylene urea (DMDHEU)/HBP adduct by crosslinking HBP with DMDHEU in presence of MCC. Furthermore, the prepared adduct was characterised by investigation its infra red and then utilised in the removal of three anionic dyestuffs from aqueous solutions, namely Irgalan Blau 3GL (an acid dye), SIRIUS Blau S‐BRR (a direct dye) and Levafix Brill Orange P‐GR (a hydrolysed reactive dye).

The results obtained revealed that the optimum conditions for preparing MCC/DMDHEU/HBP adduct are [HBP], 90 g/l; [DMDHEU], 200 g/l; LR, 1/3.3; [NC₄LH], 20 g/l; a time of 30 min and a temperature of 160°C. Moreover, the results also showed that the extent of removal of such dyestuffs from their aqueous solutions by the prepared adduct follows the order: reactive dye>acid dye>direct dye, it is more pronounced at lower than at higher pH values and the removal of each dye by that adduct follows a first‐order reaction.

Other substrates such as chitosan can be used to prepare more effective adducts.

Hyperbranched polymers can be used effectively to prepare ion exchangers capable of removing the pollutants of dyestuffs from their aqueous solutions.

The aforementioned prepared HBP is a novel hyperbranched polymer and could be applied in the removal of many other pollutants.

The feasibility of obtaining a union (solid) shade with reasonable color strength and no staining on the white ground of 50/25/25 wool/linen/viscose blended fabric printed with Levafix^® reactive dyes under different conditions was investigated. Optimum printing conditions were found to use a printing paste containing: sodium alginate (3%), 700g/kg; sodium acetate, 40g/kg; urea, 50g/kg; glycerol, 20g/kg; dye, 20 g/kg; and water, 170g/kg, followed by batching the wet prints for 24 h, before steaming at 105°C/25 minutes Batching in presence of sodium acetate brings about some physical and chemical changes in the three components of the blended fabric and the dye is distributed evenly among them to produce a solid shade with higher color strength if compared with prints in presence of sodium acetate without batching. No staining on white ground of prints was observed. Fastness properties of prints at optimum conditions are generally good to very good regarding wash, good/very good regarding rubbing (wet/dry), good regarding light, and very good regarding acidic and alkaline perspiration.

The inclusion of softeners (20 g/l), namely, Siligen VN (silicon based), Basosoft SWK (cationic), or Leomin NI (nonionic), in a dimethyloldihydroxy ethylene urea (DMDHEU, 50 g/l) finishing formulation of 65/35 cotton/polyester blended fabric, enhances the resiliency of the fabric, which is expressed as the dry wrinkle recovery angle (WRA). The fabric acquires the ability to keep a rose oil fragrance upon storage up to 3 months. Improving the WRA and acquiring the ability to keep the fragrance can be descendingly arranged as follows: Siligen VN>Basosoft SWK>Leomin NI. Increasing the Siligen VN concentration (0-30 g/l) in the finishing formulation is accompanied by a small increase in the WRA, and a noticeable enhancement in the ability to keep the rose oil fragrance upon storage. By increasing the rose oil concentration (100-300 g/l) in a perfumed bath of cross-linked/Siligen VN, the softened fabric is accompanied by a slight drop in the WRA, and a decreasing ability to keep the fragrance up to 3 months.

However, the extent of the fragrance is higher at higher rose oil concentrations, regardless of the storage time. The ability of the fabric to keep the fragrance can be attributed to solubilization and/or encapsulation of the perfume in the oleophilic segments of the softener, and its slow release with time, so that the smell can be sensed. This ability decreases after increasing the storage time up to 3 months, and depending on the type of perfume oil used, is descendingly arranged as follows: jasmine oil > rose oil > sandal oil.

Optimal conditions for condensation of equimolar ratios of stearic acid (St) and polyethylene glycol (PEG) 400, i.e. 180°C, 8hrs and H₂SO₄, 4g/kg (reactants mixture), were utilized to condensate the equimolar ratio of stearic (St), palmitic (Pa) or myristic (My) acid with PEG 300, 400, 600, 2000 or 6000. Each of the fifteen condensates was formed by total conversion (83.5 to 84.1 %). Monoester–diester ratios of the condensates ranged from 4:1 to 49:1. FT – IR spectroscopy and hydrophilic lipohilic balances (HLB) of the condensates were also examined. The condensates had softening and hydrophilic properties of cotton fabric with no yellowing at concentrations of 30 and 50g/l in the presence or absence of DMDHEU (50g/l). The presence of DMDHEU improved the fabric resiliency.

However, the softening and hydrophilic properties of the fabric were inferior in the presence of DMDHEU rather than the absence. In comparison with a commercial softener, PEG 2000- or 6000-based condensates were higher in fabric wettability and pliability but lower in smoothness. Regarding CRA, only My-2000 was comparable to that of the commercial softener in terms of effect.

Condensates of stearic (St), palmitic (Pa) or myristic (My) acids with polyethylene glycols (PEG) 300, 400, 600, 2000 or 6000, are utilized as emulsifiers for kerosene ∓ in ∓ water pigment printing pastes. Pastes based on condensates of PEG 300 or 400 are unstable while the others are stable. Rheology of stable pastes, aside from those based on a commercial emulsifier, are of a non ∓ Newtonian, shear thinning ∓ thixotropic flow. The order of the flow properties of pastes enhanced are found. Cotton pigment prints using the nine pastes are sharp and of comparable handle, colour strength and color fastness to those based on a paste of either a commercial emulsifier or synthetic thickener (except for Pa∓6000). The pigment prints of 65/35 cotton/polyester are sharp only upon using pastes of commercial emulsifier, synthetic thickener, St∓600, St∓2000, St∓6000 and My∓2000. After 7 days of storing, all pastes are stable with increased apparent viscosities and induced color strength on both cotton and blended fabrics.

Pretreatment of fabric with a number of chemicals and auxiliaries is a prerequisite for inkjet printing. Owing to the rapidly increasing use of inkjet printing for textile fabrics, the study of the effects of process variables on various characteristics of the resulting print has drawn considerable interest recently. The purpose of this paper is to study the effects of different variables associated with the inkjet printing process on the quality of the resulting print. Specifically, the effects of chemicals and auxiliaries used in the pretreatment of the fabric prior to printing and factors such as steaming time were studies.

In the present study, which forms a part of a larger study by the authors, the influence of the nature of thickener, the amounts of thickener, urea and alkali, pH of the pretreatment liquor and the duration of steaming on ink penetration into the printed fabrics and the ink spreading across the fabrics was studied. The nature of ink penetration and ink spreading are known to have pronounced effects on the quality and, in turn, the overall appearance of the resulting print. A set of experiments based on a blocked 2^5–1 fractional factorial design with four centre points were conducted to evaluate the role of the aforementioned five variables. Ink penetration was quantified on the basis of the principles of Kebulka-Munk theory while ink spreading was analysed by image analysis.

Detailed statistical analyses of the experimental data obtained show that different thickeners perform differently and can have a marked influence on ink penetration and ink spreading. In the case of polyacrylic acid-based thickener, changing the levels of the factors has a marked effect on ink penetration and in-turn on ink spreading. In the case of polyacrylamide (PAM)-based thickener, on the other hand, the effect of changing the levels of various factors on the ink penetration and ink spreading is considerably less pronounced. In addition, PAM treated samples exhibited better performance in terms of ink penetration and spreading.

This study provides useful information for textile printers and highlights the importance of selecting the right type of thickener to make the printing process and the quality of the resulting print more predictable and controllable.

The purpose of this paper was to protect carbon steel from corrosion with self–aggregated, eco-friendly, water-soluble hyperbranched polyamide-ester (Hb-PAE).

Hb-PAE was synthesized through bulk polycondensation reaction between maleic anhydride and di-isopropanol amine. Complete structural analysis for the obtained polymer was performed using Fourier Transfer Infra-Red Spectroscopy, 1H NMR, Thermal gravimetric analysis (TGA) and differential scanning calorimetry, and the molar mass was measured using gel permeation chromatography/refractive index. For this study, the surface activity of Hb-PAE with hydroxyl end groups was investigated. Surface tension of 1.0 × 10−6 to 0.1M of both Hb-PAE/H₂O and Hb-PAE/1N HCl systems was measured, and the critical aggregation concentration (CAC) in both systems was determined. Hb-PAE was examined as a corrosion inhibitor for plain carbon steel in both neutral (distilled water) and acidic (1N HCl) media. The corrosion of the steel was studied quantitatively by measuring its weight loss in both media in the absence and presence of Hb-PAE. The surface morphology of the exposed steel test samples was examined using scanning electron microscopy.

It was found that Hb-PAE inhibited corrosion of steel around the CAC, and its corrosion inhibition efficiency was increased by increasing its concentration.

The research can provide a reference for the relationship between the aggregation concentration of the prepared Hb-PAE with its corrosion inhibition efficiency on plain carbon steel. Hb-PAE as a corrosion inhibitor is environmentally acceptable, economical and readily available.

Presents findings from a study of the effects of treating unbleached bagasse paper sheets with different resin solutions. Unbleached kraft bagasse paper sheets were treated with different resin solutions such as nitrocellulose, melamine formaldehyde, silicone, short and medium alkyd resin and the physico‐mechanical properties of the modified paper sheets were tested. The strength properties of treated paper sheets were highly improved especially in the case of treatment with melamine formaldehyde and silicone resin solutions. The effect of dipping time of paper sheets in different concentrations of resin solution on the strength properties was also investigated. Physico‐mechanical properties of thermally treated modified paper sheets with resins were also clarified. Concludes that promising results in the improvement of insulation of treated paper sheets with resin are obtained by studying the dielectric‐electric properties.

The purpose of this study is to identify the most influential factors affecting the printing properties and print quality of digitally printed silk fabrics in terms of colour strength and fixation percentage.

In this study, five factors (concentration of thickener, concentration of urea, concentration of alkali, pH of pretreatment liquor and steaming duration) were investigated using a blocked 2⁵⁻¹ fractional factorial experiment. The type of thickeners [polyacrylic acid and polyacrylamide (PAM)] were considered as a block.

Linear models were obtained and statistically tested using both analysis of variance and coefficient of determination (R²), and they were found to be accurate at 90 per cent confidence level. It was revealed that concentration of alkali, concentrations of urea and pH of the pretreatment liquor had an increasing effect on colour strength, whereas concentration of thickener and steaming duration showed decreasing effect on colour strength of digitally printed silk fabrics. Furthermore, concentration of alkali, concentrations of urea had increasing effect on dye fixation percentage, whereas steaming duration showed decreasing effect on dye fixation percentage of digitally printed silk fabrics. In addition, PAM thickener based pretreatment recipe exhibited better printing properties for the digitally printing of silk fabrics.

The main influences and significant two-factor interactions were discussed in detail to gain a better understanding of the printing properties of digitally printed silk fabrics. The findings of this study are useful for further optimisation of pre- and post-treatment processes for digital printing of silk fabrics.