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Poly (acrylic) starch composites were prepared by polymerizing acrylic acid, acrylamide alone or in admixtures with maize starch using KMnO4/citric acid as redox initiation. The cooked composite pastes were used as partial substituent of kerosene oil emulsion in the pigment printing pastes for cotton fabric. Printing was carried out under a variety of conditions including neutralization of the free carboxylic groups of the polyacrylic acid component in the composite or AA/Aam mixtures, composite concentration, and the type of pigment dyes. The effect of storage on the efficiency of the printing paste was also examined. The printed samples were assessed for colour strength (K/S) overall fastness properties. Results obtained indicate that:

Hydroxypropyl starch (HPS) is synthesized by using maize starch and different concentrations of both propylene oxide )PO) and sodium hydroxide (NaOH) with the intent to obtain HPS products which can better serve as a reducing and stabilizing agent during the preparation of silver nanoparticles. Such a preparation is carried out under a variety of conditions which include: pH, temperature, duration of the reaction medium, molar substitution (MS) of HPS, and concentration of both HPS and silver nitrate (AgNO3). The yield of silver nanoparticle colloids is monitored via color and ultraviolet (UV) visible spectral analyses whereas their evaluation is performed by making use of a transmission electron microscopy (TEM) to determine size and size distribution. The results obtained conclude that the optimum conditions for preparation of silver nanoparticle colloids with excellent size and size distribution which range from 6-8 nm could be produced by using 0.9 gm of HPS (MS = .84), 0.425 gm of AgNO3, a pH of 12, and temperature of 70°C for 15 minutes. Furthermore, the silver nanoparticle colloid solution prepared under these conditions is stable and remains without aggregation for more than six months. Thus preparation of a well stabilized silver nanoparticle solution with a concentration of 1608 ppm and a diameter of 9-18 nm can be achieved. A silver nanoparticle solution with these unique characteristics may be suitable for industrial applications.

Nano-sized silver particles at a concentration of 1620 ppm were prepared using hydroxypropyl starch (HPS) as a reductant of silver nitrate and a stabilizer for silver nanoparticles. A solution containing 1620 ppm silver nanoparticles was diluted to 50 ppm and 100 ppm. The diluted solution was applied to cotton fabrics in the presence and absence of a binder to impart antibacterial properties to the fabrics. The solution containing 50 ppm silver nanoparticles with 1% binder (Printofix® Binder MTB EG liquid) induces excellent and durable bactericidal activity in cotton fabrics. The finished fabrics were examined for morphological features and surface characteristics by making use of the SEM. The SEM pictures reveal that silver nanoparticles are deposited on the surface of fibrils (fabric fibres).

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.

To explore the use of power ultrasound as an environmentally friendly heating technology for the pre‐treatment of linen fibres with sodium perborate as the halogen free oxidising agent and to study the impact of this process on its dyeability with reactive dyes.

Exploiting power ultrasound in the wet processes of linen fibres was made in two steps, i.e. ultrasonic pre‐treatment with sodium perborate followed by ultrasonic dyeing with reactive dyes. Therefore, comparative studies between conventional and ultrasonic techniques as well as the different factors that may affect these processes were investigated. The effect of the pre‐treatment on fibre fine structure using X‐ray diffraction technique was also investigated.

The results of the increase of whiteness index indicate that ultrasonic pre‐treatment was better at all studied treatment times and at low temperature. X‐ray diffraction studies on blank, ultrasonically and conventionally pre‐treated linen fibres have shown 70.41, 67.51 and 64.90 per cent crystallinity, respectively. The dyeing of the pre‐treated fibres with Reactive Red 24 was simultaneously carried out under both ultrasonic and conventional heating conditions to study the effect of dye concentrations at different dyeing temperatures. The colour strength values obtained for the dyed samples using ultrasonic at 50°C were slightly higher than those obtained using conventional heating at 80°C. Ultrasonic enhancement in the pre‐treatment and dyeing in terms of the percent increase of colour strength of the dyed fabric was estimated to be 157.94 per cent higher than that of conventional heating method. The results of wet fastness properties of the dyed fibres using ultrasonic revealed improvement relative to those obtained using conventional heating method.

The improved wet processes of linen fibres suggest further investigation to exploit power ultrasound in the wet processes of cellulosic fibres at low temperature using different classes of halogen free bleaching agents and dyeing with different classes of heat‐requiring reactive dyes. Also, this work may inspire the synthesis of new generation of heat‐requiring reactive dyes.

The work presented has significant potential industrial application for cleaner production in textile industries.

The present study of linen pre‐treatment with non‐toxic total chlorine free oxidising agent and its dyeability with reactive dyes using power ultrasound is novel and could be used in the wet processes of linen fibres.

Wood as a structural material has one feature which is unique among all structural materials; it is a crop which can be formed, whereas its competitors such as stone, brick, metal and plastic are all derived from exhaustible mineral sources.

The behaviour of chemically modified cellulose towards dyeing is an interesting subject. Cellulose undergoes substantial changes in its chemical and physical properties by chemical modification. Some investigations were carried out to study the effect of these changes on dyeing and dyeing properties of cellulose. Previous reports have disclosed that the dyeability of chemically modified cellulose differs significantly when compared with the unmodified cellulose. Among the modified cellulose studied were partially acetylated cellulose, cyanoethylated cellulose, carboxymethylated cellulose, cellulose tiaocarbonate and cellulose copolymerized with various vinyl monomers.

This study aims to explore the incorporation of starch nanoparticles (SNPs) in cross-linking formulation of cotton fabrics to see their impact on fabric performance like tensile strength, dry wrinkle recovery angles, elongation at break, degree of whiteness and increase in weight as well as durability.

SNPs of size around 80-100 nm were successfully prepared from native maize starch by Nano precipitation technique and confirmed instrumentally by scanning electron microscope (SEM), transmittance electron microscope (TEM), Fourier transformer infrared (FTIR) spectroscopy and particle size analyzer. The latter were incorporated in cross-linking formulation of cotton fabrics encompassing different concentrations of citric acid and sodium hypophosphite at different curing time and temperature in 100 ml distilled water to a wet pickup of ca. 85 per cent. The fabric samples were dried for 3 min at 85°C and cured at specified temperatures for a specified time intervals in thermo fixing oven according to pad-dry-cure method.

FTIR spectra and SEM micrograph signified the chemical structure and surface morphology of cotton fabric before and after finishing in absence and presence of SNPs. Cotton fabric samples finished in presence of SNPs showed a higher tensile strength, elongation at break, comparable dry wrinkle recovery angles and degree of whiteness than that finished in their absence. On the other hand, the enhancement in the aforementioned performance reflects the positive impact of incorporation of SNPs in textile finishing especially with strength properties; which are one of the important requirements for industrial fabrics that can be used widely in heavy-duty applications.

SNPs with its booming effect with respect to biodegradability, reactivity and higher surface area can be used as a novel reinforcement permanent finish for cotton fabrics instead of more hazardous materials likes poly acrylate and monomeric compounds.

As SNPs biopolymers is one of the important reinforcement agents, so it was expected that it would minimize the great loss in strength properties during easy-care cotton finishing and improve the fabric performance.

The novelty addressed here is undertaken with a view to remediate some of the serious defects of easy-care cotton fabrics using poly carboxylic acids; especially with the great loss in strength properties by virtue of using SNPs as a permanent finish. Besides, to the authors’ knowledge, there is no published work so far concerning the use of SNPs as an innovative base for production of easy-care finished cotton textiles with high performance.

Samples of loomstate cotton fabric were first treated with aqueous potassium permanganate solution at different concentrations in the presence of a non‐ionic wetting agent. The samples were then washed and treated using solutions containing methacrylic acid, wetting agent and acid or basic dye along with citric acid of different concentrations at different temperatures for different times. The critical properties of the fabric such as graft yield (expressed as carboxyl content m.eq/100g cellulose), colour strength before and after soaping and percentage loss in colour strength due to soaping were found to depend on the concentrations of KMnO₄, citric acid and methacrylic acid as well as duration of the treatment. Based on the results obtained, treating formulations consisting of KMnO₄ (0.1g/l), citric acid (0.1g/l), methacrylic acid (50 per cent), dye (1 per cent) and wetting agent (2g/l) was considered appropriate for concurrent grafting and dyeing of the said fabrics provided that the treatment was carried out at 90°C for 60 minutes.

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.