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This study aims to use multi-functional viscose fabric that was facilely developed with with respect to ease and care characteristics, reinforcement effect and antibacterial activity by using novel echo friendly antibacterial finish based on citric acid/sodium hypophosphite and the authors’ previously tailor-made poly meth acrylic acid (MAA)-chitosan graft copolymer via alternative microwave curing approach instead of traditional high-temperature cure one.

Viscose fabric was paddled twice in the cross-linking formulations containing different concentrations of citric acid, poly (MAA)-chitosan graft copolymer and sodium hypophosphite to 90 % wet pick up and dried at 100°C for 3 min in an electric oven. Then, the treated fabrics were placed on the disk spinner of the microwave oven and cured at different power (100–800 Watt) for various durations (60–180 s). The fabric was then water-rinsed and dried at ambient condition before use.

Results revealed that the above echo friendly method for finished viscose fabrics was found to achieve relatively high dry wrinkle recovery angle and maintain the loss in tensile strength within the acceptable range, as well as antibacterial activity against Escherichia coli and Staphylococcus aureus as a gram-negative and gram-positive bacteria, respectively; in addition to durability up to ten washing cycles. Furthermore, scanning electron microscope images, nitrogen content and add on % of the finished fabric confirmed the penetration of grafted chitosan inside the fabric structure. The tentative mechanism for these reactions is advocated.

The novelty addressed here is undertaken with the advantages of using citric acid as a nonformaldehyde, safe and cheap poly carboxylic acid as a crosslinking agent and sodium hypophosphite as a potential catalyst, in addition to the authors’ noncitable multifunctional echo friendly tailor-made poly (MAA)-chitosan graft copolymer for imparting reinforcement and antibacterial characteristics to viscose fabric that uses the pad-dry/cure microwave fixation for progressively persuaded heat within the fabric during curing.

This was done to see the impact of microwave as green and efficient tool with respect to reduction in organic solvents, chemicals and exposer time as well as fixation temperature on the finishing reaction in comparison with traditional pad-dry-cure method.

Poly (MAA)-chitosan graft copolymer as amphoteric biopolymer was expected to impart multifunctional properties to viscose fabrics especially with comparable dry wrinkle recovery angle and minimize the loss in tensile strength in addition to antibacterial properties in comparison with untreated one.

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.

Herein, this study aims to use our recently tailored and fully characterized poly acrylonitrile (AN)-starch nanoparticle graft copolymer having 60.1 graft yield percentage as a starting substrate for copper ions removal from wastewater effluent after chemical modification with hydroxyl amine via oximation reaction as a calorimetric sensor.

The calorimetric sensor batch technique was used to determine the resin's adsorption capacity, while atomic adsorption spectrometry was used to determine the residual copper ions concentration in the filtrate before and after adsorption. This was done to convert the copolymer's abundant nitrile groups into amidoxime groups, and the resulting poly (amidoxime) resin was used as a copper ion adsorbent. To validate the existence of amidoxime groups, the resin was qualitatively characterized using a rapid vanadium ion test and instrumentally using Fourier transform infrared spectroscopy spectra and scanning electron microscopy morphological analysis.

At pH 7, 400 ppm copper ions concentration and 0.25 g adsorbent at room temperature, the overall adsorption potential of poly (amidoxime) resin was found to be 115.2 mg/g. The process's adsorption, kinetics and isothermal analysis were examined using various variables such as pH, contact time, copper ion concentration and adsorbent dose. To pretend the adsorption kinetics, various kinetics models, including pseudo-first-order and pseudo-second-order, were applied to the experimental results. The kinetic analysis indicated that the pseudo-second-order rate equation promoted the development of the chemisorption phase better than the pseudo-first-order rate equation. In the case of isothermal investigations, a study of observed correlation coefficient (R²) values indicated that the Langmuir model outperformed the Freundlich model in terms of matching experimental data.

To the best of the author's information, there is no comprehensive study for copper ions removal from waste water effluent using the recently tailored and fully characterized poly (AN)-starch nanoparticle graft copolymer having 60.1 graft yield percentage as a starting substrate after chemical modification with hydroxyl amine via oximation reaction as a calorimetric sensor.

Several research and developmental work attempts have been made in this manuscript to synthesize what is called tailored polymeric materials with new characteristics based on pregelled starch through a number of processes which, in turn, entail several chemical treatments. This is done by subjecting pregelled starch as a starting substrate to acid hydrolysis to obtain different molecular sizes. Pregelled starch with different molecular sizes are carbamoylethylated by using acrylamide and sodium hydroxide at different durations, then grafted with different monomers by using a potassium permanganate/citric acid redox system to initiate grafting. Furthermore, application of the newly tailored pregelled starch derived products as a sizing agent of cotton textiles is systematically studied. It is shown from the data that (a) the extent of carbamoylethylation expressed as N% increases by increasing the extent of hydrolysis and duration; (b) the graft yield expressed as mmol. monomer/100 g sample of different monomers onto carbamoylethylated and carbamoylethylated hydrolyzed pregelled starches increases by increasing the extent of carbamoylethylation and degree of hydrolysis, and follows the order: methacrylamide (MAam) > methacrylonitrile (MAN) > methacrylic acid (MAA), and (c) cotton fabrics sized with grafted carbamoylethylated hydrolyzed pregelled starch acquire higher mechanical properties, i.e. TS, elongation at break, and abrasion resistance values than hydrolyzed, carbamoylethylated and carbamoylethylated hydrolyzed pregelled starches. Finally, the use of the above tailored modified pregelled starch derived products in the sizing of cotton textiles contribute to reinforcement of the cotton textile after sizing to overcome the forced loss in fabrics/yarns during the spinning process as shown above.

The inhibitive effect of some morpholine and thiosemicarbazide derivatives on the dissolution of aluminium in 2M HCI has been investigated by using thermometric, weight loss and hydrogen evolution techniques. The effect of the inhibitors on the protection efficiency and the corrosion rate were determined at various inhibitor concentrations and temperatures. It was observed that the percentage inhibition of aluminium increases with the increase of inhibitor concentration and decreases with rise of reaction temperature. Retardation of dissolution is due to weak adsorption of the additives on the metal surface. The order of inhibition efficiency of the inhibitors used depends on the number of adsorption sites in the molecule, their charge density and molecular size.

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.

The novelty addressed here is undertaken by using tailor-made and fully characterized starch nanoparticles (SNPs) having a particle size ranging from 80 to 100 nm with a larger surface area, biodegradability and high reactivity as a starting substrate for cadmium ions and basic dye removal from wastewater effluent. This was done via carboxylation of SNPs with citric acid via esterification reaction using the dry preparation technique, in which a simple, energy-safe and sustainable process concerning a small amount of water, energy and toxic chemicals was used. The obtained adsorbent is designated as cross-linked esterified starch nanoparticles (CESNPs).

The batch technique was used to determine the CESNPs adsorption capacity, whereas atomic adsorption spectrometry was used to determine the residual cadmium ions concentration in the filtrate before and after adsorption. Different factors affecting adsorption were examined concerning pH, contact time, adsorbent dose and degree of carboxylation. Besides, to validate the esterification reaction and existence of carboxylic groups in the adsorbent, CESNPs were characterized metrologically via analytical tools for carboxyl content estimation and instrumental tools using Fourier-transform infrared spectroscopy (FTIR) spectra and scanning electron microscopy (SEM) morphological analysis.

The overall adsorption potential of CESNPs was found to be 136 mg/g when a 0.1 g adsorbent dose having 190.8 meq/100 g sample carboxyl content at pH 5 for 60 min contact time was used. Besides, increasing the degree of carboxylation of the CESNPs expressed as carboxyl content would lead to the higher adsorption capacity of cadmium ions. FTIR spectroscopy analysis elucidates the esterification reaction with the appearance of a new intense peak C=O ester at 1,700 cm⁻¹, whereas SEM observations reveal some atomic/molecules disorder after esterification.

The innovation addressed here is undertaken by studying the consequence of altering the extent of carboxylation reaction expressed as carboxyl contents on the prepared CESNPs via a simple dry technique with a small amount of water, energy and toxic chemicals that were used as a sustainable bio nano polymer for cadmium ions and basic dye removal from wastewater effluent in comparison with other counterparts published in the literature.

The purpose of this study is to investigate the authors' previously prepared and fully characterized poly (methacrylamide)-chitosan nanoparticles (CNPs) graft copolymer having 50.2% graft yield with respect to flocculation efficiency for ferric laurate aqueous dispersions. This was done to compare the ability of the latter cheap, biodegradable and ecofriendly hybrid natural-synthetic polymeric substrate as a flocculant in comparison with higher cost, nonbiodegradable and harmful polyacrylamide as a well-known synthetic flocculant counterpart.

The graft copolymerization process was carried out at 450°Cfor 120 min using (1.0 g) CNPs, methacrylamide (1.5 g), 100 mmol/l potassium chromate and 80 mmol/l mandelic acid. Fourier transform infrared spectroscopy, thermogravimetric analysis, elemental analysis and specific viscosity were used to characterize and analyze the resultant copolymer. The flocculation efficiency was conferred in terms of transmittance % and weight removal %. The main factors influencing the flocculation process, such as flocculent dose, flocculation medium pH, stirring speed, flocculation temperature and grafting extent, were comprehensively discussed.

The flocculation efficiency of the prepared copolymers revealed the following findings: increased by increasing the flocculant dose, pH, temperature and stirring speed to a maximum values denoted at 30 ppm, 6.0, 30°C and 50 r/min, respectively, then decreased thereafter; increased by increasing the extent of grafting within the range studied; showed a comparable flocculation efficiency in comparison with polyacrylamide as a synthetic polymeric flocculent; and, finally, a preliminary bridging mechanism representing the attraction between the anionic suspended particles ferric laurate and cationic poly (MAam)-CNPs graft copolymer has been projected.

The advancement addressed here is undertaken with using the authors’ poly (MAam)-CNPs graft copolymers having different extent of grafting (a point which is not cited in the literature especially for the authors’ prepared copolymer) as a hybrid natural-synthetic polymeric substrate as a flocculant for ferric laurate aqueous dispersions in comparison with the high cost and nondegradable polyacrylamide synthetic flocculant.

The purpose of this paper is to generate nitrogen-containing groups in the cotton fabric surface via low-temperature nitrogen plasma as an eco-friendly physical/zero-effluent process. This was done for rendering cotton dye-able with Acid Blue 284, which in fact does not have any direct affinity to fix on it.

Dyeing characteristics of the samples such as color strength (K/S), fastness properties to light, rubbing and perspiration and durability, as well as tensile strength, elongation at break, whiteness, weight loss and wettability in addition to zeta potential of the dyed samples, were determined and compared with untreated fabric. Confirmation and characterization of the plasma-treated samples via chemical modifications and zeta potential was also studied using Fourier transform infrared spectroscopy (FTIR) and Malvern Zetasizer instrumental analysis.

The obtained results of the plasma-treated fabric reflect the following findings: FTIR results indicate the formation of nitrogen-containing groups on cotton fabrics; notable enhancement in the fabric wettability, zeta potential to more positive values and improvement in the dyeability and overall fastness properties of treated cotton fabrics in comparison with untreated fabric; the tensile strength, elongation at break, whiteness and weight % of the plasma treated fabrics are lower than that untreated one; and the durability of the plasma treated fabric decreased with increasing the number of washing cycles.

The novelty addressed here is rendering cotton fabrics dye-able with acid dye via the creation of new cationic nitrogen-containing groups on their surface via nitrogen plasma treatment as an eco-friendly and efficient tool with a physical/zero-effluent process.

This study aims to explore the incorporation of the authors previously prepared chitosan nanoparticles (CNPs) of size around 60-100 nm in the cross-linking formulation of viscose fabrics to see CNPs impact in terms of imparting multi-functional characteristics such as tensile strength, dry wrinkle recovery angles and antibacterial properties.

CNPs of size around 60-100 nm were incorporated in cross-linking formulations for viscose fabrics, including different concentrations of glutaraldehyde as a non-formaldehyde cross-linking agent and magnesium chloride hexahydrate as a catalyst. The formulations were applied at different curing times and temperatures in 100 mL distilled water, giving rise to a wet pickup of ca. 85 per cent. The fabrics were dried for 3 min at 85°C and cured at specified temperatures for fixed time intervals in thermo fixing oven according to the traditional pad-dry-cure method.

The above eco-friendly method for finished viscose fabrics was found to obtain high dry wrinkle recovery angle and maintain the tensile strength of the finished fabric within the acceptable range, as well as antibacterial properties against Escherichia coli and Staphylococcus aureus as a gram-negative and gram-positive bacteria, respectively. Both, scanning electron microscope and nitrogen percent on the finished fabric confirm the penetration of CNPs inside the fabric structure. Finally, viscose fabrics pageant antibacterial activity against gram-positive and gram-negative bacteria assessed even after 20 washing cycle.

CNPs with its flourishing effect with respect to cationic nature, biodegradability, reactivity, higher surface area and antimicrobial activity; in addition to glutaraldehyde as non-formaldehyde finishing agent can be used as multi-functional agents for viscose fabrics instead of DMDHEU, polyacrylate and monomeric composites as hazardous materials.

CNPs as cationic biopolymers were expected to impart multi-functional properties to viscose fabrics especially with obtaining reasonable dry wrinkle recovery angle and tensile strength in addition to antibacterial properties.

The novelty addressed here is undertaken with a view to impart easy care characteristics and antibacterial activities onto viscose fabrics using CNPs as antimicrobial agent and glutaraldehyde as non-formaldehyde durable press finishes to-replace the traditional formaldehyde-based resins. Besides, to the authors’ knowledge, there is no published work so far using the above cross-linking formulation written above.