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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.

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 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.

A graft copolymer (PBW-g-PAM) of Moringa seed was prepared. The phosphate buffer washed seed powder and polyacrylamide were reacted, using ceric ion initiator. The grafted copolymer was tested for its efficiency for metal removal (Cr-VI) from tannery effluent and for color removal from textile effluent using standard spectroscopic methods. The paper aims to discuss these issues.

The PBW-g-PAM was prepared by standard method and characterized by FT-IR, SEM, UV-vis, XRD and DSC/TGA analyses.

The effects of PBW-g-PAM dose, contact time and pH on percent removal of Cr-VI and dye color, have been reported.

The efficiency of metal removal was shown to be 99 per cent in just 15 min. Similar results were obtained for efficient color removal from textile effluents. It is for the first time that graft polymer of Moringa seed has been used for metal and color removal.

This paper aims to study previously prepared and fully characterized chitosan nanoparticles (CNPs) as a starting substrate and microwave initiation technique for grafting acrylic acid (AA). This was done to see the influence of both CNPs with respect to well-dispersed nanosized particles, large surface areas, biodegradability, biocompatibility and reactivity and microwave initiation technique with respect to reduction in organic solvents, toxic chemical initiator and exposer time on exploiting the graft yield % and enhancing water solubility and antibacterial properties.

For evaluating the best accurate standard metrological method for calculating the graft yield %, the grafting parameters were stated in terms of graft yield percent and measured gravimetrically (based on dry weight method) and titrimetrically (based on carboxyl content). Microwave power, AA and CNPs concentrations and reaction duration were shown to be the most important parameters influencing the grafting process.

The optimum reaction conditions were obtained when CNPs 1.5 g, AA 150 bows, microwave irradiation power 500 W and reaction duration 120 s were used. Various analytical methods were used to characterize CNPs and poly(AA)–CNPs graft copolymers. According to the findings, Fourier transform infrared spectroscopy examination determines the attachment of carboxyl groups to CNPs chains. The thermogravimetric analysis revealed that the copolymers were more thermally stable than CNPs counterparts. Furthermore, the resulting copolymers were shown to have greater water solubility biodegradability resistance and antibacterial properties than CNPs counterpart. Finally, a preliminary mechanism demonstrating all occasions that occur during the polymerization reaction has been proposed.

The advancement addressed here is undertaken using previously prepared and fully characterized CNPs as a green bio-nanocompatible polymer and microwave initiation technique as green and efficient tool with respect to reduction in organic solvents toxic chemical initiator and exposer time for grafting AA.

This paper aims at studying the oxygen plasma treatment and the previously prepared and fully characterized chitosan nanoparticles (CNPs) as a green and eco-friendly strategy for surface modification of viscose fabric. This was done to render viscose fabric dye able with two types of acid dyes that do not have direct affinity to fix on it via improving the fabric wettability.

To achieve the goal, viscose fabric was activated with oxygen plasma at optimum conditions and coated with different concentrations of CNPs solution via conventional pad dry cure technique. The untreated and plasma-treated fabrics with CNPs were dyed with two types of acid dyes, namely, Acid Orange 7 and Methyl Red under determined conditions. The color strength (K/S), fastness properties to light, rubbing and perspiration, add on %, tensile strength, wettability and durability of the dyed samples were determined and compared.

The results divulged that oxygen plasma-treated fabric with CNPs and the aforementioned dyes in question could improve the flowing properties in comparison with untreated fabric: (a) the fabric wettability expressed as wetting area mm²; (b) the dye ability and fastness properties of viscose fabrics expressed as K/S and fastness properties; and (c) the strength properties and add on % of the treated fabric. On the other hand, the durability of the plasma-treated fabric decreased with increasing washing cycles.

The novelty addressed here was using plasma treatment as an eco-friendly pre-treatment approach for attachment of CNPs as a multifunctional green bio-nano polymer onto viscose fabric, which improved the dyeing properties of the fabric with acid dyes that do not have direct affinity to fix onto it.

This study aims to demonstrate that orange-derived and lemon-derived systems can be used in continuous processes as efficient adsorbents to the entrapment of some anionic and cationic dyes in the textile dyeing wastewater effluents.

Physically and chemically modified orange and lemon mesocarps are used as natural adsorbents for the cationic dyes Basic Blue 3, Basic Yellow 21, Basic Red 18 and Basic Green 4 and the anionic dyes Acid Blue 264, Acid Yellow 49 and Acid Red 337, all commonly used in the textile dyeing industry. Adsorption capacities of the orange-derived and lemon-derived adsorbents on the dyes are studied simulating a batch and continuous industrial processes.

Results demonstrate that treated orange mesocarp (orange-derived adsorbent) can adsorb up to 97% of cationic Basic Green 4 in 30 min, whereas the lemon mesocarp (lemon-derived adsorbent) can retain up to 88% within the same time. In the case of anionic, 91% Acid Blue 264 is adsorbed by the orange mesocarp in 15 min, whereas 92% is adsorbed by the lemon homologue within the same time.

As far as the authors know, physically and chemically modified orange and lemon mesocarps have not been used on the removal of cationic (Basic Blue 3, Basic Yellow 21, Basic Red 18 and Basic Green 4) and anioinic (Acid Blue 264, Acid Yellow 49 and Acid Red 337) dyes of textile dyeing wastewater industry. It is a costless and efficient treatment that supposes, on the one hand, an eco-friendly and feasible process for discolouration of wastewater and, on the other, a valorisation (upcycling) of orange and lemon peels, which are not currently used.