Coloration and surface modification of woven polyester (PET) fabric with bio-based Logwood dye and plasma technology have been researched to develop a greener textile finishing process. The effect of atmospheric pressure air dielectric barrier discharge on the surface of the polyester fabric has been studied using specific wettability measurements (water contact angle-WCA and % capillarity), scanning electron microscopy (SEM), and zeta potential assessments. A striking enhancement of capillarity percentage from 1.6% to 108% for the plasma-treated polyester was revealed, suggesting that special chemical elements such as hydroxyl, carbonyl, and carboxyl groups were incorporated on its surface, thereby raising its hydrophilic behavior. Furthermore, pretreatment based on the plasma surface activation mechanism improved the dyed polyester fabric's color strength (K/S). The extent of dye absorption and color fastness properties were highly related to the main pad-dyeing conditions adopted (temperature) and the influence of fabric surface modification treatment selected (air atmospheric plasma treatment and/or deposition of chitosan biopolymer).

The final colour prediction of a weave design made of dyed yarns is a difficult problem. This study shows how a geometric model can be developed to obtain the final colour prediction objectively. For this purpose, a woven material was divided into weft, warp and pores. Then, all parameters needed for the calculation of each colour contribution were identified. A geometrical model based on construction parameters was developed to predict the surface colour contribution of each coloured yarn in a weave surface. To validate the predicted colorimetric data, a visual assessment experiment was conducted. Then, the difference between the predicted and actual colour appearance of the weave pattern was evaluated and analysed in function of weaving structures, and weft yarns colours. For this purpose, simple woven structures (plain, twill 1/3, basket 2/2 and satin Turc) with four coloured weft yarns were used. Results show that the proposed model could correctly predict the final colour of weave designs. Therefore, the model has the potential to eliminate subjective evaluations and reduce prototype sample production by automating the process of weave/colour simulation, thereby reducing the cost and time for product development. The methods of utilization of colour in woven textiles depend upon the composition of the weave design to be woven and the structure parameters of the cloth.

New fluorescent 4-alkoxyphenyl-nitrothiophene compounds 4a-d bearing diverse alkoxyl tails are described. The synthetic strategy was simply accomplished by alkali-assisted alkylation of 4-(5-nitrothiophen-2-yl)phenol (3) with propyl, hexyl, nonyl, and/or dodecyl iodide. The molecular structures were determined using infrared (IR), 1 H NMR, and mass spectroscopy. Ultraviolet-visible (UV-vis) absorption and emission spectra of the produced 4-alkoxyphenyl-nitrothiophenes revealed considerable extinction coefficients, which were shown to be controlled by the thiophene bridge in conjugation with the alkoxy donor moiety. It was found that the maximum absorbance wavelength was affected by the alkoxyl group-bonded substituents. The antioxidant efficiency obtained from the 4-alkoxyphenyl-nitrothiophene hybrids was excellent compared with that widely used drugs [butylated hydroxytoluene (BHT) and vitamin C]. Unlike 2-(4-[dodecyloxy]phenyl)-5-nitrothiophene hybrid 4d, which has made solid claims about the good effect of its reference drugs and vitamins, Docking investigations of the prepared 4-alkoxyphenyl-nitrothiophene hybrids towards the selected 5IKQ protein revealed impressive coordination and antioxidant effectiveness.

The aims of this study are to stop biofouling formation and to create antibacterial layers on aquaculture nets using a chemical product known for its antibacterial behavior. Polyamide 6.6 and high-density polyethylene nets were grafted with polyethylene glycol by following two methods. At first, grafted nets were evaluated with SEM and XPS in order to study the morphological and chemical information. Then, the antibacterial activity was studied at laboratory scale by measuring the rate of adhesion, on nets, of three bacterial strains (Pseudoalteromonas citrea, Pseudoalteromonas elyakovii, and Vibrio harveyi). Results highlighted that the surface of the ungrafted nets was the most colonized by bacteria, with a progressive increase in bacterial adhesion over the time. For PA 6.6 and HDPE nets, the best antibacterial behavior was noted on nets grafted with PEG after surface activation at 45 °C.

Marine biofouling seriously affects the field of aquaculture. On the one hand, it causes structural fatigue of nets and on the other hand, it has harmful consequences on the health of farmed species. The aims of this study were to develop antibacterial nets using methacrylic acid and dyes. At first, polyamide 6.6 nets were grafted with methacrylic acid following two methods and dyed with 3 specific dyes. Then, modified nets were evaluated with SEM and XPS to obtain morphological and chemical information. Moreover, the antibacterial activity of nets was assessed against three bacterial strains at a laboratory scale and at a real scale by calculating the Colonies Forming Units (CFU) / gram. All treated nets showed an inhibition level higher than 65%. Besides, nets dyed with direct dye Tubantin and grafted with MA after plasma activation, showed an inhibition level higher than 95%. Also, nets modified with MA after plasma and reactive dye Bezaktiv S showed the best antifouling activity against three bacteria strains.

This article explains the development of an enantioselective durable material that is based on a cross-linked & beta;-resorcylic acid-resorcinol-formaldehyde copolymer for the chiral recognition of S-cathinone (CTN) and the effective enantioseparation of the (& PLUSMN;)-CTN racemic mixture. In a first step, a polymerizable S-CTN-& beta;-resorcylic acid amide was produced and characterized through elemental analysis, Fourier transform infrared (FTIR), and nuclear magnetic resonance (NMR) spectroscopy. Thereafter, the obtained chiral amide was copolymerized with resorcinol-formaldehyde by means of acidic condensation polymerization, and the resulting polymeric resin was treated with sodium hydroxide and subsequently HCl to remove the S-CTN template molecules. The molecularly imprinted polymer that was formed was characterized through scanning electron microscopy, FTIR, and energy dispersive X-ray spectroscopy and then tested for selective extraction of S-CTN. Adsorption was carried out in line with the Langmuir model, and the findings showed that the maximum capacity was 205 & PLUSMN; 2 mg/g at a pH of 7. Moreover, the optical separation was performed utilizing a column, with results showing approximate enantiomeric excess values of 65% and 95% inside the supernatant and eluant solutions, respectively, for S- and R-CTN.

This study aims to provide an ecofreindly coloration process of polyester fabric with cochineal-based natural dye using the advanced waterless technology of plasma combined with padding techniques. The impact of plasma treatment was characterized by water contact angle and capillarity measurements and the resulting dyeing performances were compared in terms of color strength (K/S) and fastness properties according to standard methods. Experimental results revealed that surface activation mechanism increased successfully both wettability behavior and color strength of the polyester fabric. Indeed, up to a 40% enhancement of the wet pick-up rate of dye solutions on plasma treated substrate was observed as compared to untreated sample, whereas different fastness properties according to the selected padding conditions used, were noted.

The aim of this paper is to develop a textile waste-based composite material with adequate mechanical, acoustical, and thermal properties for automotive or construction fields. For this purpose, three recycled nonwoven wastes including cotton, polyester, and cotton/polyester blend are employed and blended in epoxy resin. The manufacturing of the composite panels is performed by vacuum infusion technique. Mechanical, thermal and acoustical tests are conducted to characterize the performances of both nonwoven fabrics and composite panels. Theoretical Young’s moduli of different composites are calculated based on the rule of mixtures in two ways and compared with practical results. Results show that mechanical properties of the manufactured panels are significantly improved compared to pure resin without a notable change in the thermal behavior of the epoxy resin, where composite reinforced cotton nonwoven shows a specific Young’s modulus of 3500 MPa/g·cm −3 and a specific tensile strength of 38 MPa/g·cm −3 . These panels have been found to be promising materials to decrease the noise emission and good alternatives to pure epoxy products due to their contribution to reducing the textile wastes in landfills as well as the production costs.

The objective of this paper is to identify the presence, direction and time at which the pure contagion effect occurred between financial markets. In so doing, the aim is to prove the existence of both spatial and temporal asymmetries of pure contagion effects. Firstly, a new empirical framework is proposed in order to define a spatial contagion index using the conditional cumulative distribution function as a parameter to estimate a conditional copula. This methodology enables us to estimate a dynamic conditional copula, providing information about how the market sent pure contagion effects and when. Secondly, in addition to detecting the direction of contagion, the real-time contagion effect is determined, enabling us to calculate the delay of contagion effects (spillover) between financial markets. The present empirical results show the existence of both spatial and temporal asymmetry for bilateral contagion effects for 16 mature and emerging stock markets during the 2001–2018 period. This proves the importance of taking temporal asymmetry into account when we want to detect the contagion effect of every crisis and to estimate the period of pure contagion relating to investors’ behaviors. Finally, these findings highlight the fact that contagion effects were more intensive during the subprime crisis than they were during the European debt crisis.

A novel natural dye Corchorus olitorius L. was investigated in the preparation of printing pastes for screen printing of cotton fabric. To ensure ecological printing, greener thickeners were used such as: sodium alginate, carboxymethyl cellulose and Ceratonia siliqua L. flour. The nature and concentration of thickener, dyestuff and urea concentrations, mordant type and fixation method were explored. Printed cotton fabric qualities were evaluated by determining different parameters: color strength, penetration percentage, printing fastnesses and mechanical properties, whereas print paste quality was evaluated by measuring its apparent viscosity. The higher dye concentration used in the printing paste led to better apparent viscosity and color strength levels. The increase of urea concentration improved the color strength, but reduced the apparent viscosity of printing paste. Best results of viscosity and color strength parameters were obtained using ferrous sulfate as a mordant and sodium alginate as a thickener, the results being 1346.67 mPa s-1 and 4.90, respectively. The resulting color shades varied from green to brown and very good color fastnesses was achieved, but depended mainly on the used experimental conditions.

The aim of this study is to build an efficient hybrid treatment process for the depollution of mixed and highly polluted industrial textile wastewater. The proposed system consists of an effective coupling between adsorption by activated carbon and a phase separation by a hydrocyclone. The response surface methodology using the Box-Behnken experimental design was applied and explored in order to optimize the most influencing factors. The experimental results showed that the decolorization efficiency (CR%) by activated carbon for Novacron Blue 4R ( NB4R) dye was 87.15% under optimal treatment conditions with a pH of 11, a concentration of carbon of 12.42 g/L and an initial dye concentration of 62.50 mg/L. The optimization study of separation of activated carbon by the hydrocyclone allowed a separation efficiency (ES%) about 88.74%. The cited efficiency was ensured in the optimal conditions which were a volume flow rate of 81.83 L/min, a carbon concentration of 12.42 g/L with a size of 0.5 m. The proposed hybrid process is shown to be more efficient in terms of treatment efficiency and recovery of the carbon particles. In addition, big improvements were reached especially in the term of the final wastewater quality after adsorption/hydrocyclone combination when compared with the current conventional treatment method in the concerned industry.

A hydrophobic polyester fabric with a prior surface activation using a dielectric barrier discharge (DBD) treatment was successfully dyed with natural Logwood dye (Haematoxylum campechianum L.) applying successive padding steps. Chemical and physical surface modifications were characterized by specific wettability measurements (water contact angle-WCA and % capillarity), scanning electron microscopy (SEM), zeta potential assessments and chemical quantification assay using ortho toluidine blue dye (TBO) before and after the DBD experiment. Padding processes without and with an ecofriendly formaldehyde-free acrylate binder and bioactive agent chitosan, were tested and the resulting dyeing performances were compared in terms of color strength and fastness properties. Significant color strengths were noted on the plasma activated polyester fabrics without the use of mordants. Results were highly dependent of the selected padding method used. While color intensity (K/S) depended on fixation temperature, the plasma treatment enhanced the K/S values and led to very good wash fastness (4/5). Combination of plasma treatment and acrylate binder further enhanced the fastness including rub fastness (4/5). In addition, results showed that the wet pick-up rate of dye solution was 40% higher after plasma treatment. This result was related to the new chemical and physical modification of polyester fiber surface properties after plasma treatment. Dyeing of plasma treated polyester fiber with a bio-based logwood dye without any addition of metallic mordant while imparting antibacterial properties, was found to be a promising strategy opening up a suitable eco-option for replacing some of the hazardous dyes and intermediates used in textile dyeing.

The aim of this study is to enhance the fiber-matrix interface of cotton waste reinforced composite panels by a specific chemical treatment. For this purpose, cotton fibers are treated in sodium hydroxide (NaOH) solution with three different concentrations (0.5 M, 1 M, and 1.5 M) and three different soaking times combinations (1 h, 3 h, and 5 h). Mechanical evaluation of treated and untreated reinforcements and composite panels are characterized using tensile test whereas the chemistries of fiber reinforcements are investigated using Fourier-transform infrared spectroscopy analysis and the fiber-matrix interactions are morphologically examined using scanning electron microscopy. Results indicate a remarkable enhancement in mechanical properties of composites via improving the interfacial adhesion and compatibility between fiber and matrix with a significant increase of Young modulus up to 270% for reinforcements and to 70% for composite materials compared to untreated materials.

In this study, real wastewater from a dyeing factory and previously treated by biological processes was decolorized by Fenton oxidation. Direct and reactive dyebaths and the related auxiliaries constituted the polluted effluents. A synthetic wastewater was also prepared in the same way in order to compare degradation performance. The study was performed with a systematic approach, searching optimum values of H2O2 and FeSO4 concentrations, pH, temperature and the chemical structure of each tested dye. Depollution results showed that the oxidation behaviour of synthetic and real wastewaters was very similar, especially during the first stage where the breaking of chromophore groups allowed fast colour removal. However, it was found that higher ratios of [H2O2]/[FeSO4] must be engaged in the case of real wastewaters. Results also showed that the catalytic oxidation yielded a fast and complete depollution at [H2O2]/[FeSO4] = 70, pH 3 and temperature 40°C. For experiments with direct dye, colour and COD removals were, respectively, 90% and 87% in the case of real wastewater. Reactive real wastewater showed non-stable oxidation evolution due to the hydrolysed dyestuff and this led to 83% and 45% decolourization and COD removal, respectively. Better depollution results were noted for the synthetic wastewater experiments. This finding was related to the non-stable composition of the real wastewater and the unknown chemical and physical interferences between its compounds. After sedimentation, reuse of the treated wastewater for new dyeing experiments was also investigated. For this purpose, the whole process was run under complete recycling mode and the previously treated effluent was re-used as fresh dyebath. Results in terms of colour depth and fastness showed that dyeing performances were very similar, and an important opportunity is offered by reusing wastewater treated by Fenton oxidation process.

This study explores the influence of functionalization process of cellulosic structure on its mechanical and comfort properties. Chitosan hydrogel has been synthetized and applied on cellulosic fabric to impart pH-sensitivity and antimicrobial behavior. The hydrogel bounded rate onto the surface was enhanced by a previous chemical activation of cotton fabric. Antimicrobial behavior was confirmed by investigation of the antibacterial activities against Escherichia coli, Listeria monocytogene and Staphylococcus aureus bacteria. The pH stimuli-responsiveness behavior was also confirmed and the pH-dependency swelling of the chitosan hydrogel was successfully transformed into cellulosic sites. The resulting fabric was confirmed suitable for medical, surgical and also transdermal therapy applications. Meanwhile, these modifications have unexpectedly altered basic mechanical and comfort properties. It was established that the proposed antimicrobial treatment caused slight decrease in air permeability and made the support thickener. The obtained results revealed also that tensile behavior and the ultimate comfort properties were greatly influenced by the chemical activation.

•Biofouling appears on any immersed structure in seawater. It causes many problems on aquaculture fields.•Antifouling formulations have been proposed to control the biofouling. They were found to be toxic on different species.•PA nets were modified by applying products used in textile field. Dyes with a very low percentage of copper were employed.•Nets were modified by grafting technique with Methacrylic Acid and atmospheric air plasma treatment.•The evaluation towards the accumulation of bacteria and algae was done by using physical and biological techniques.

ABSTRACTIn this work, chitosan hydrogel has been synthesized and used to impart pH‐sensitivity and antimicrobial finish to cotton fabric. In order to enhance the incorporation rate of hydrogel, anionic, and cationic activation of the textile surface was applied and then compared. The antibacterial activity of the fabric was then studied. The results revealed an enhancement of the antibacterial activities of the modified fabrics against Escherichia coli, Listeria monocytogene, and Staphylococcus aureus bacteria's. The capacity of material to respond to pH change was studied and confirmed using contact angle method. The anionic fabric treated with hydrogel showed a better pH‐responsiveness. Scanning electron microscopic testing results has also confirmed that the deposition of hydrogel was clearly better with the anionic activation. The characteristics of breathability of the fabrics were analyzed. The results show that the moisture management behavior of the finished materials is significantly better than the control one. Although the permeability to air has reduced by 10%, the permeability to water vapor remained practically unchanged. Furthermore, the effects of the antibacterial finishing on the physical properties of the cotton fabrics were also investigated. It was established that the functionalized samples have changed structure parameters, thickness, air permeability, tensile strength, and resistance to wrinkles. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46645.

The production infrastructure in aquaculture invariably is a complex assortment of submerged components with cages, nets, floats and ropes. Cages are generally made from polyamide or high density polyethylene (PEHD). All of these structures serve as surfaces for biofouling. However, cage nets and supporting infrastructure offer fouling organisms thousands of square meters of multifilament netting. That's why, before immersing them in seawater, they should be coated with an antifouling agent. It helps to prevent net occlusion and to increase its lifespan. Biofouling in marine aquaculture is a specific problem and has three main negative effects. It causes net occlusion and so restricts water and oxygen exchange. Besides, the low dissolved oxygen levels from poor water exchange increases the stress levels of fish, lowers immunity and increases vulnerability to disease. Also, the extra weight imposed by fouling causes cage deformation and structural fatigue. The maintenance and loss of equipment cause the increase of production costs for the industry. Biocides are chemical substances that can prohibit or kill microorganisms responsible for biofouling. The expansion of the aquaculture industry requires the use of more drugs, disinfectants and antifoulant compounds (biocides) to eliminate the microorganisms in the aquaculture facilities. Unfortunately, the use of biocides in the aquatic environment has proved to be harmful as it has toxic effects on the marine environment. The most commonly used biocides in antifouling paints are Tributyltin (TBT), Chlorothalonil, Dichlofluanid, Sea-Nine 211, Diuron, Irgarol 1051 and Zinc Pyrithione. Restrictions were imposed on the use of TBT, that's why organic booster biocides were recently introduced. The replacement products are generally based on copper metal oxides and organic biocides. This paper provides an overview of the effects of antifouling biocides on aquatic organisms. It will focus on the eight booster biocides in common use, despite little data are available for some of them. Toxicity values and effects of these antifoulants will also be mentioned for different species of fish, crustaceans, invertebrates and algae.

It is attempted in the present investigation to treat a synthetic textile effluent containing indigo dye by indirect electro-oxidation. Electrochemical degradation process was performed using Graphite as anode and Stainless Steel as cathode. The influence of effluent pH, supporting electrolyte concentration and the current intensity on pollutant degradation were studied. The best removal of organic compounds contained in the waste has been obtained at pH 13, low electrolyte concentration and current intensity (0.1M and 200 mA, respectively). COD and percentage colour removal were 75% and 43% respectively. Due to its effectiveness and ease in operation, this technique can be applied for treatment of a large volume and industrial scale of textile wastewater.