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Polyacrylamid-guar gum composite has been prepared via graft copolymerization of acrylamide onto guar gum using the KBrO₃/ thiourea redox system. The amide groups (40%) in the composite are converted to reactive groups through methylolation with formaldehyde, with a view to obtaining reactive composite. The composite and the reactive composite were used as pastes for printing cotton fabrics with pigment dyes. The prints were assessed for color strength (K/S) and overall fastness properties.

Printing was carried out under different conditions, including the amount of composite used as a substitute for kerosene emulsion, the amount of binder incorporated into the printing paste and the types of catalysts. The printed samples were evaluated by monitoring the color strength (K/S) and fastness properties such as washing, rubbing and light. Based on the results obtained, it is concluded that a partial substitution ratio of 20/75 (composite/kerosene emulsion), 8gm binder/100gm printing paste and 1% of catalyst (NH4Cl, DAP, Citric acid or [NH4]2SO4) represent the proper formulation for gaining good dye fixation and excellent fastness properties. The results indicate that the reactive composite prepared is the most suitable thickener for printing cellulosic fabrics with pigment dyes.

The purpose of this paper is to prepare ultra-violet (UV)-curable inkjet inks for textile printing application. The influence of both type and component ratio of monomer/oligomer on the quality of the desired viscosity range is studied. Moreover, the effect of pigment/resin ratio on the rheological behaviour of the ink has been studied.

Aqueous dispersions of nanoscale organic pigments were prepared through ball milling and ultrasonication. The dispersed pigments were encapsulated into UV-curable resin via miniemulsion technique, using different types and component ratios of monomers and oligomers.

It was found that the monomer/oligomer ratio of 2:3 and the pigment/resin ratio of 2:1 gave the most stable miniemulsion dispersions and provided the most suitable rheological range for inkjet printing inks.

As the rheology of the ink is optimised, most of the problems associated with the jetting process could be avoided.

This method of using UV-curable encapsulated inks eliminates the usage of binders, which are the principal factor for nozzle clogging of the print head. In addition, binders are responsible for the coarse handle of the printed textiles.

The UV-curable inks were viewed as a green technology by the US Environmental Protection Agency.

This method is simple and fast and requires low cost. In addition, it could find numerous applications in surface coating.

The line of balance (LOB) method is a suitable scheduling technique that managers can use to support lean planning efforts for projects composed of repetitive activities such as high-rise building construction. Like any other method, LOB has certain disadvantages that create a set of practical limitations in its application. An LOB schedule gives insights about how continuous and synchronized single resources are scheduled and how uniform these resources are distributed over the project duration. However, these three characteristics have to be visually checked, which makes the evaluation and the comparison of different schedule alternatives difficult. To overcome this problem, the purpose of this paper is to present a quantitative method to calculate quality degrees for the continuity, the synchronization and the uniformity of an LOB schedule that can be applied to assess an LOB schedule globally.

The paper introduces a set of global indicators, termed quality degrees, which allow for a quick quantitative evaluation of LOB schedules at the global level. These quality degrees are quantitative indicators for the: degree of continuity, degree of synchronization and degree of uniformity within a specific LOB alternative. A mathematical model was developed to calculate the quality degrees for LOB schedules. This model was validated using a well-known case study extracted from literature, and its practical implementation was exemplified on two real Romanian projects.

The paper illustrates this contribution using two case studies that confirm that the proposed method can be used to evaluate different schedule alternatives. In particular, the paper shows that quality indicators can be used to analyze and control interdependencies between cost and time.

The main limitation of the proposed method is that it cannot indicate the desired level of continuity, synchronization or uniformity to be achieved. Further studies need to explore this possibility, as well the relationship between indicators.

The presented quality indicators contribute to existing LOB methods as they allow for the quick analysis and assessment of schedules without an in-depth visual analysis.

The paper proposes an innovative method, mathematically formulated, to quantitatively assess the quality aspects of continuity, synchronization and uniformity for LOB schedules.

Functionalization of organic cotton fabrics (OCFs) by in situ deposition of chitosan reduced-stabilized silver nanoparticles (AgNPs). No other toxic chemicals used to warrant an ecofriendly synthesis protocol. Human toxicity of silver systematically avoided to use as textile clothing. Primary colors (nearly-red, yellow and blue) were imparted on OCFs via localized surface plasmon resonance (LSPR) of AgNPs. Decent mechanical properties and laundering durability in terms of antibacterial/fastness test improved mechanical properties.

Silver nanoparticles can be synthesized by using silver nitrate along with commercially available chitosan. Due to the surface LSPR property of silver nanoparticles, it exhibits versatile colors depending on the synthesizing procedures. The coloration occurs due to the electrostatic interaction between the AgNPs and chitosan-treated OCF. The nanotreated fabrics provide excellent mechanical properties with improved antibacterial effects.

X-ray fluorescence (XRF) analysis quantifies the developed materials in the substrates. Scanning electron microscopy (SEM) characterization indicates the appearance and morphologies of silver nanoparticles into the fabric surface after the coloration process. It proves that the treated cotton knit fabric exhibits the LSPR optical features of AgNPs. The antibacterial and mechanical properties confirm the improved functionality of products.

Improved mechanical properties, antibacterial performances and coloration effects on organic cotton substrates in terms of chitosan-mediated nanosilver are not yet studied.

The purpose of this study was to prepare partially methylolated polyacrylamide-guar gum via graft copolymerization of acryalmide and guar gum using the potassium bromate/thiourea redox system.

Using HCHO (40 per cent), amide groups in the composite are converted to reactive composite. The reactive composites (N-methylolated [PAam-GG]) were used as pastes for printing cotton fabrics with pigment dye, under a variety of conditions. Variables studied include the amount of binder incorporated into the printing paste and different catalysts incorporated into the printing paste.

Characterization of printing samples under different conditions, including amount of the beneficial effects of varying conditions of printing on the color strength (K/S); the color parameters L, a, b, h and c; and the change in color difference (ΔE) were also investigated. The Fourier transforms infrared spectra of printed cotton fabrics has followed each condition of printing. The obtained results indicate that the improvement in the printing process may be due to change in molecular configuration as a result of the variation in chemical bond.

The present research aims to manage the formulations of pigment-based inks containing aminopropyl/vinyl/silsesquioxane (APSV) as a pigment binding agent for inkjet printing of polyester as a commercial trial for the printing of polyester as a single-step process.

The proposed formulations incorporated APSV by using the mini-emulsion technique at a low relieving temperature under the thermal initiation or UV radiation of vinyl-terminated groups in APSV. In this study, the storage stability of inks with regard to physical properties was broadly examined. Moreover, the color performance, including colorimetric data, color fixation and fastness properties of printed fabrics was evaluated.

The results indicated that the inks containing APSV were formulated and were stable in terms of particle size, dispersion stability, surface tension and viscosity over a period of one month and for four freeze/thaw cycles. APSV successfully fixed the pigment-based inkjet inks on polyester fabric and could achieve a significantly higher color performance and degree of fixation than the formulated inks without APSV.

It could also fulfill all the physical properties of ink prerequisites over storing and eliminating all challenges in improving the performance and utilization of inkjet printing.

APSV can also be used as a pigment binding agent to formulate inks for inkjet printing of polyester fabrics as the authors’ past examination for inkjet printing of polyester fabrics post-treated with APSV.

This study eliminates the noteworthy challenges in formulating the pigment-based inks for textile applications by incorporation of a binder while keeping up the necessary viscosity profile for a specific print head.

This study addressed all the issues arising from the complex nature and very challenging requirements of inkjet inks.

Perfluoroheptyl methacrylate was copolymerized with acrylamide using different ratios of these monomers. The copolymers so obtained were methylolated with formaldehyde. The methylolated copolymers were used as multi‐purpose finishing agents for cotton. They impart oil and water repellence. Attachment of the methylolated copolymer to cotton is presumed to involve chemical bonds via reaction of the methylol groups of the copolymer and the hydroxy groups of cotton cellulose. This was evidenced by the wash‐fastness properties; no significant differences were noted in the oil/water repellence of cotton fabric treated with the copolymers in question.

The purpose of this paper is to prepare and characterise various ink formulations for inkjet printing on nylon 66 carpet.

Various ink formulations were prepared using CI Acid Red 57, synthetic thickeners (BYK425 and BYK420), ethylene glycol, diethylene glycol, isopropanol with auxiliaries. The inks were characterised for their rheological, wetting and storage stability properties. The inks were jetted using a Printos P16 drop‐on‐demand jet print‐head onto nylon 66 carpet materials. The printed images were characterised using an ImageXpert system.

It is found that the inks containing the synthetic thickeners at the optimum ratio give good printing and image properties, such as optical density, drop size, and depth of penetration into the substrate at pH 4‐5. The optimised ink formulation is found to have good storage stability.

The study focuses on ink formulations based on CI Acid Red 57. Ink formulations based on other colorants could also be studied in order to assess the applicability of the ink formulation system found for other colorants.

The ink formulations developed could find use in industrial scale printing.

Low cost ink formulations for printing of nylon carpets are novel.

The purpose of this paper was to synthesize novel antibacterial reactive dyes for dyeing cotton fabrics.

Four synthetic novel antibacterial reactive dyes based on sulfonamide (D1-D4) have been synthesized by the coupling reaction of sulfonamide diazonium salt with sulfonamido-cyanurated 7-amino-4-hydroxynaphthalene-2-sulfonic acid “j-acid”. The chemical structure of the synthesized dyes was secured by their spectral data [infra red (IR) and proton Nuclear magnetic Resonance (1HNMR)].

The prepared reactive dyes (D1-D4) were applied to cotton fabrics. Optimum conditions of the dying samples at sodium sulfate 100 g/l, liquor ratio (L.R.) 1:10, sodium carbonate 20 g/l at 80°C (D1, D2 and D4), 60°C (D3 for 60 min) were investigated. The fastness properties toward washing, perspiration, rubbing and light were evaluated. Dyed fabrics showed good light fastness property and good to very good washing and perspiration fastness properties according to the gray scale. Antimicrobial activities for synthesized dyes showed excellent activity against gram-negative organisms such as Pseudomonas aeruginosa and Proteus mirabilis faecalis, whereas very good activity against gram-positive organisms such as Staphylococcus aureus and Enterococcus faecalis with respect to the standard drugs ampicillin and chloramphenicol.

The principle advantages in this study were that the synthesis of novel synthesized dyes by introducing bisulfonamide-based moieties to increase the antimicrobial activity of the cellulose fabrics could be used as a medical textile, short reaction time and reaction procedure conducted in few steps, the work up is convenient and thus the starting material can be easily prepared.

The purpose of this study is to undertake surface graft copolymerization of viscose fabric via altering its fibrous properties by using acrylic acid (AA) as a carboxyl-containing monomer and peroxydisulfate (PDS) in presence of ferrous sulfate as a novel redox pair for initiating grafting. The latter process acted as an energy-saving process with respect to the reduction in polymerization temperature and maximizing the graft yield %, in addition to rendering the grafted viscose fabrics dye-able with cationic dye (crystal violet), which has frequently no direct affinity to fix on fabric.

To make graft copolymerization more efficient and economic, the optimum conditions for graft copolymerization were established. The graft yield % was determined as a function of initiator, catalyst and monomer concentrations and the material to liquor ratio, in addition to polymerization time and temperatures. Metrological characterizations via Fourier transform infrared spectroscopy and scanning electron microscopy of topographic morphological surface change have also been established in comparison with the ungrafted samples.

The maximum graft yield of 70.6% is obtained at the following optimum conditions: monomer (150 % based on the weight of fabric), PDS (50 m mole), ferrous sulfate (80 m mole) and sulfuric acid (30 m mole) at 40° C for 1.5 h using a liquor ratio of 30. Remarkably, grafting with AA enabled a multifold upsurge in color strength, with improvements in the fastness properties of cationically dyed grafted viscose fabric measured on the blue scale in comparison with untreated viscose fabric.

The novelty addressed here is undertaken with studying the effect of altering the extent of grafting of poly (AA)-viscose graft copolymers expressed as graft yield % in addition to carboxyl contents on cationic dyeing of viscose fabric for the first time in the literature. Moreover, rendering the viscose fabrics after grafting is dye-able with cationic dye with high brilliance of shades, which has regularly no direct affinity to fix on this type of fabrics.