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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.

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:

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.

Carbamoylethyl starch (CrES) and cyanoethyl starch (CES) were prepared by making use of the concept of the dry process under conditions which were developed to form the bases of environmentally sound (clean) technology. The obtained CrES and CES were saponified using alcoholic NaOH solution. The CrES and CES along with their saponified products were further modified by subjecting them to graft polymerization with Aam/AN mixture. Saponification of the so‐obtained grafted substances was also carried out. Presents the findings of these investigations which are explained in terms of structural changes in the starch, the ‐CN and CONH₂ groups, the Aam/AN polymeric graft and the site of attachment of the latter on the modified starch.

This study aims to address a comprehensive and integrated investigations pertaining to the preparation of AgNPs with well-defined nano-sized scale using the aforementioned poly (meth acrylic acid [MAA])–chitosan graft copolymer, which is cheap, nontoxic, biodegradable and biocompatible agent as a substitute for the traditionally used toxic reducing agents.

AgNPs are prepared under a range of conditions, containing silver nitrate and poly (MAA)–chitosan graft copolymer concentrations, time, temperature and pH of the preparation medium. To classify AgNPs obtained under the various conditions, ultraviolet–visible spectroscopy spectra and transmission electron microscopy images are used for characterization of AgNPs instrumentally in addition to the visual color change throughout the work. The work was further extended to study the application of the so prepared AgNPs on cotton fabric to see their suitability as antibacterial agent as well as their durability after certain washing cycles.

According to the current investigation, the optimal conditions for AgNPs formation of nearly 3–15 nm in size are 5 g/l, poly (MAA)–chitosan graft copolymer and 300 ppm AgNO₃ in addition to carrying out the reaction at 60°C for 30 min at pH 12. Besides, the application of the so prepared AgNPs on cotton fabric displayed a substantial reduction in antibacterial efficiency against gram-positive and gram-negative bacteria estimated even after 10 washing cycles in comparison with untreated one.

To the best of the authors’ information, no comprehensive study of the synthesis of AgNPs using poly (MAA)–chitosan graft copolymer with a graft yield of 48% has been identified in the literature.

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.

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).

Incorporation of either EDTA or β-cyclodextrin in the bioscouring treatments and its onset on the bioscoured fabrics performance was intensively studied. Biotreatments involved single use of alkaline pectinase enzyme or in combination with cellulase enzyme in a subsequent treatment. EDTA and β-cyclodextrin were entailed independently in the bioscouring by using two strategies: 1) they were applied to the fabrics as a pretreatment and; 2) they were added to the bioscouring treating solution. Fabrics used were enzymatically desized. Desized fabrics under investigation comprised cotton fabric, mercerized cotton fabric, cotton/polyester (50/50) blend fabric and cotton/polyester (35/65) blend fabric. Results showed that pretreatment of fabrics with EDTA followed by subsequent bioscouring by alkaline pectinase enzyme in single use or in combination with cellulase enzyme in a separate step decreases the performance of bioscoured fabrics. On the other hand, incorporation of EDTA in the bioscouring solution containing alkaline pectinase enzyme alone or together with an extra treatment in the bioscouring solution containing cellulase improves the performance of the bioscoured fabrics. It was also found that addition of β-cyclodextrin to the bioscouring solutions containing alkaline pectinase enzyme alone or supported by cellulase enzyme in a separate step acts in favour of the technical properties and performance of the bioscoured fabrics.

A thorough investigation into conditions appropriate for effecting combined eco-friendly scouring and bleaching of cotton based fabrics was undertaken. Loomstate cotton and blend fabrics were desized by α-amylase enzyme. Fabrics were the target for bioscouring using alkaline pectinase enzyme, bleaching by in-situ formed peracetic acid using TAED and H²O² as well as concurrent bioscouring and bleaching which is considered by all means a new development. Also, practiced were the conventional scouring using NaOH followed by bleaching using H²O² and other bleaching processes vis-à-vis the new current development. The comparison reveals unequivocally that the environmentally sound technology brought about by current development is by far the best. The new development involves a single-stage process for proper purification / preparation of cotton and blend fabrics . through removal of noncellulosic impurities and colouring matters . by padding the fabrics in a bath containing alkaline pectinase enzyme, TAED, H²O², nonionic wetting agent and sodium silicate. In addition to the advantages related to major technical fabric properties, the new development is eco-friendly and reproducible, which advocates the new development for mill trials.