Influence of temperature on corona discharge treatment of cotton fibers

In this study, corona discharge treatment was applied to modify the surface of cotton fibers at various temperatures. The fiber surface was roughened during this treatment and the surface oxygen content increased at a considerably low temperature, and then declined when temperature increased. Weight loss rate showed the treatment was fiercer as treated temperature increased. The breaking strength and surface adhesion property of the fabric treated with starch sizing increased to a certain extent and then decreased. These results suggest that the treated temperature plays a great role in the surface properties of cotton fiber when treated via corona discharge.     

Improvements of surface functionality of cotton fibers by atmospheric plasma treatment

This study aims to investigate the viability of atmospheric plasma treatment over raw cotton fabric surfaces as an alternative method for superseding the wet textile pre-treatment processes. For this purpose, the fabric samples were treated with air plasma and argon atmospheric plasma. Thereafter, the hydrophilicity and the wickability of plasma treated samples increased, and also the contact angles decreased significantly. Chemical changes were analyzed by FTIR-ATR and XPS. Morphological changes were observed by SEM. The results were inspected for assessing to what extent the replacement might be achieved by inducing this surface modification method.     

Characteristics of silver-plated silk fabric with plasma pre-treatment

Plasma gases of oxygen and argon were employed for pre-treating silk fabric before conducting electroless silver plating in this study. The effect of plasma pre-treatment with oxygen and argon gases on the electroless silver-plated silk fabric was investigated. Based on the observation of micro-structure using SEM, it was found that there was an increase in the amount of silver particles deposited on the silk fibre surface after plasma pre-treatment. The functional properties of plasmainduced electroless silver-plated silk fabrics were also evaluated. The increase in weight of the silver-plated silk after plasma pre-treatment was determined. When compared, the oxygen plasma treatment could improve the effect of silver plating on the silk fabric. Additionally, anti-static, anti-bacterial, UV protection and water-repellent properties of the silver-plated silk fabric were determined in this study.     

Influence of low temperature plasma treatment on the properties of ink-jet printed cotton fabric

The aim of this paper is to study the possibility and effectiveness of applying LTP treatment to enhance the performance of pre-treatment paste containing sodium alginate so as to improve the properties of the ink-jet printed cotton fabric. Experimental results revealed that the LTP pre-treatment in couple with the ink-jet printing technique could improve the final printed properties of cotton fabric.     

The effect of alkali pre-treatment on formation and adsorption of silver nanoparticles on cotton surface

This study is an attempt to investigate the feasibility of alkali pre-treatment to activate surface hydroxyl groups of cellulose fibers in order to enhance the deposition efficiency of silver nanoparticles (AgNPs) onto cotton fabrics. Cotton samples were pre-treated with various alkali solutions containing different earth metal hydroxides (LiOH, NaOH, and KOH). The as-prepared samples were then treated with aqueous silver nitrate followed by reduction treatment with aqueous ascorbic acid, which caused in situ formation of AgNPs on fiber surfaces. The surface structure of the fabrics was characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) analysis, and colorimetric data. The amount of silver was measured by using inductively coupled plasma-optical emission spectrometer (ICP-OES). Antimicrobial activity was measured against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli bacteria. It was established that alkali pre-treatment had a substantial effect on the formation and adsorption of AgNPs on the fibers. Alkali pre-treated samples were homogeneously coated by AgNPs with high surface coverage. Alkali type had significant effect not only on the amount of AgNPs on the surface but also on its size. High antibacterial activity against both Gram-positive and Gram-negative strains was also demonstrated, even after 10 cycles washing.     

Comparison between oxygen and nitrogen plasma treatment on adhesion properties and antibacterial activity of metal coated polypropylene fabrics

In this paper, an attempt was made to apply low temperature plasma treatment to improve the adhesion property of polypropylene fabrics. Oxygen and nitrogen plasmas were used for pre-functionalization of polypropylene fabrics. Then treated and untreated samples were coated with copper using direct current magnetron sputtering for 10 minutes. And the effect of oxygen and nitrogen pre-functionalization on adhesion properties between copper particles and polypropylene surface were studied. The textile properties of treated and untreated samples were evaluated by different standard testing methods in terms of both physical and chemical performances. The morphology changes of fabrics after plasma treatment were characterized by scanning electron microscopy. Fourier transform infrared spectroscopy analyses revealed chemical surface modifications occurring after the plasma treatments. Experimental results of the adhesion properties and surface properties are presented for the metal coated-polypropylene samples before and after low pressure plasma treatment, and results are compared. The adhesion properties of the activated samples are determined by abrasion and rubbing tests. The antibacterial counting test was used for determination of antibacterial efficiency of both treated and untreated samples, and durability of antibacterial properties was compared. The adhesion improvement has been related to the formation of different functional groups and changes in the topology of the surface.     

Application of analytic hierarchy process for the selection of cotton fibers

In many engineering applications, the final decision is based on the evaluation of a number of alternatives in terms of a number of criteria. This problem may become very intricate when the selection criteria are expressed in terms of different units or the pertinent data are difficult to be quantified. The Analytic Hierarchy Process (AHP) is an effective way in dealing with such kind of complicated problems. Cotton fiber is selected or graded, in the spinning industries, based on several quality criteria. However, the existing selection or grading method based on Fiber quality Index (FqI) is rather crude and ambiguous. This paper presents a novel approach of cotton fiber selection using the AHP methodology of Multi Criteria Decision Making.     

Influence of chitosan on the effects of proteases on wool fibers

Textile processes generally produce a large amount of wastewater and cause a negative environmental impact. The use of proteases in wool finishing could be an appropriate alternative to classical finishing methods. However, the enzymatic treatment could cause excessive fiber damage. The application of biopolymer chitosan on wool fabrics prior to proteases treatment in attempt to overcome the damage promoted by the enzymes has been studied. The treatments based on chitosan application followed by enzymatic treatment reduce felting shrinkage, enhance whiteness degree, and improve dyeability of wool. Moreover, it plays an important role in minimizing the wool fiber damage.     

Effect of color changes of naturally colored organic cotton fibers on human sensory perception

This study aims to investigate the color changes of Naturally Colored Organic Cotton (NaCOC) fibers after scouring, and to evaluate the human sensory perception for the fibers. Furthermore, it tries to observe the relationship between the color coordinates and the sensory perception. Three colors (ivory, coyote-brown, green) of NaCOC fibers were scoured under four different treatments (boiling water, enzyme, sodium carbonate, sodium hydroxide). The color coordinates (L, a, b) were measured in CIELAB using spectrophotometer (SP62, X-Rite), and color differences (ΔL, Δa, Δb, ΔE) were calculated. Human sensory perception for the NaCOCs was evaluated by 27 female participants. The questionnaire consisted of nine pairs of bipolar visual sensory adjectives using the SDS. The values of L and b fell, while the value of a arose after scouring in general. The value of ΔE was the highest when treated with alkali solutions among all treatments. Human sensory perception such as brightness, clearness, lightness and freshness generally decreased, while vividness and strength increased. The meaningful color factors to predict brightness, lightness were L and ΔL, and those to predict vividness and strength sensory were ΔL.     

Water and oil-repellent coatings of perfluoro-polyacrylate resins on cotton fibers: UV curing in comparison with thermal polymerization

UV curing of perfluoro-alkyl-polyacrylate resins able to impart water as well as oil-repellency to cotton fabrics was studied in comparison with conventional thermal polymerization. The process was assessed through weight gain and gel content measurements while the properties conferred to cotton fabrics were determined in terms of water and oil contact angles, moisture adsorption, and water vapor permeability. The polymerization yields were of the same order (>80 %) of those obtained with thermal curing as well as the high contact angles with water (>127°) and oil (>118°) even at low resin add-on (3 %). UV cured resins yielded oil contact angles mostly higher than 120° denoting super oil-repellent surfaces. Moreover the water and oil-repellency was adequately maintained after washing. The moisture adsorption of finished fabrics was lower than that of untreated cotton, but slightly higher for UV cured than thermally treated fabrics. Water vapor transmission rate showed that the finish treatment, thermal as well as by UV curing, does not reduce the breathability of the original cotton. DSC analysis demonstrated that the fiber pyrolysis is affected by the polymer add-on, while FTIR-ATR spectra of all finished fabrics showed typical peaks of ester and C-F groups. XPS analysis showed small differences between thermal and UV curing coatings with each resin, while coatings with the lowest percentage of fluorine groups did not affect the water and oil-repellency.     

Study on the influence of scouring on the wettability of keratin fibers before plasma treatment

The present paper studies the wetting behavior and shrink-resistance of keratin fibers prepared by solvent extraction or by industrial-like surfactant washing as well as their response to plasma treatments. The results obtained reveal that keratin fibers can be prepared by surfactant washing instead of using solvents, which will allow carrying out research studies in closer conditions to the industrial reality, and indeed in a much economic and environmentally friendly way.     

新疆机采棉加工工艺对棉花质量的影响

为了研究新疆机采棉加工工艺在清理杂质的同时对棉花品质的影响,围绕典型的新疆机采棉加工工艺,从4道籽棉清理前后、轧花前后、3道皮棉清理前后等环节取样、测试,探讨棉花品质指标(含杂率、上半部平均长度、长度整齐度指数、断裂比强度)在新疆机采棉加工过程中的变化规律,分析含杂率与棉纤维上半部平均长度、长度整齐度指数、断裂比强度之...     

Influence of water hardness on acid dyeing with silk

In this paper, the effect of water hardness, expressed in CaCO₃ equivalent, on the dyeing silk with acid dye under acid, alkaline and isoelectric point dyeing conditions was studied by zeta potential method. Under acid condition and in the presence of calcium ion, the positive zeta potential of silk was found to decrease with a reduction in the dye adsorption. Such a phenomenon might be due to the presence of cation which increased the dyeing potential barrier at the interface between fibre and dye solution. This would result in a higher resistance of dye anions passing through the interface. Under alkaline condition, the zeta potential on silk was negative and resulted in a strong potential barrier for the dye anions. The presence of calcium ion would result in a decrease in the absolute value of zeta potential of silk fibre with an overall increase in dye absorption. Under isoelectric point, the zeta potential of silk fibre was found to be near zero and dye adsorption was not influenced by the cations. When studying the effect of calcium ion on the silk dyeing with acid dye under acid, alkaline and isoelectric point dyeing conditions, it was found that calcium ions influenced dye exhaustion and fixation greatly under acidic and alkaline dyeing conditions, which such influence became much smaller when the pH of dyebath was at the isoelectric point of the fibre. These results showed that calcium ion could produce strong electrolytic effect on dyeing even under very low concentrations.     

Investigating the effect of Water-oil repellency finish on baby clothes

In this paper, fuzzy logic method was used to model the effect of stain repellent treatment on plush knitted fabrics intended for baby clothes. In order to reduce the complexity of the models and increase the knowledge and comprehension of the underlying process, a fuzzy sensitivity variation criterion was used to select the most relevant parameters which are taken as inputs of the reduced fuzzy logic models. The outputs are the water-oil contact angles characterizing the stain repellent behavior of fabrics and the percentage of decrease of air permeability to control the change of hygienic comfort. Obtained results showed that the hydrophilic samples were transformed to water-oil repellent ones and some experimental conditions induce a high contact angle without affecting the air permeability.     

Influence of alkali treatment on the structure and properties of hemp fibers

Alkali treatment may change the structures and properties of cellulosic fibers. The aim of this work was to study the mechanism of structural changes of hemp fibers treated with different alkali concentrations and time by SEM, FTIR, tensile and bending tests. The results showed that the alkali treatment removed some of non-cellulosic materials from the surface of fibers and caused many cracks along the axis of fibers. The crystalline order index increased firstly followed by decreased with the increase of concentration. The deconvolution spectra in OH stretching region showed that the alkali treatment decreased the amount of hydrogen bonding firstly and then increased. The S/G ratio results also support the removal of non-cellulosic materials. The tensile strength of the fibers increased with the alkali concentration. Furthermore, the suitable chemical treatment not only slenderized the hemp fibers, but also softened the fibers dramatically.     

Microwave assisted fabrication of Nano-ZnO assembled cotton fibers with excellent UV blocking property and water-wash durability

Nano-ZnO assembled cotton fibers, with excellent UV blocking property and good water-wash durability, have been successfully fabricated using microwave assisted precipitation and crystallization process synchronously in situ for the first time. Here, zinc nitrate hexahydrate was used as zinc resource and sodium hydroxide was used as precipitate. The asobtained samples were characterized by powder X-ray diffractometer (XRD), filed emission scanning electron microscopy (FESEM), and energy-dispersive spectrometry (EDS), UV/Visible spectroscopy and Fourier transformation infrared spectroscopy (FTIR). Wurtzite ZnO with about 30–40 nm in diameter was fabricated in the lumen as well as in mesoporous structures of cotton fibers. The as-prepared samples have excellent UV absorbing activity over a broad range in the region from 225 nm to 380 nm. The crystallinity and UV blocking properties keep unchangeable as the former after being washed for 60 min in 33 l water. FTIR results reveal that there is no peak shift and new peak occurred, which indicates that no chemical bond exist between nano-ZnO and cotton fibers. Mechanical force is the only way to bond nano-ZnO to cotton fibers in the experimental condition. ZnO nanoparticles and wax existing in cotton fibers can combine to a firmly hybrid layer in the surface and the inner of cotton fibers during microwave treatment, which may bring the good water-wash durability.     

The structure of wool fibers grafted with chitosan coated Ag-loading nano-SiO2 antibacterial composites

Wool fiber was grafted with chitosan coated Ag-loading nano-SiO₂ (CCTS-SLS) antibacterial composites under ultraviolet irradiation. The morphologies and structures of CCTS-SLS-wool were characterized by using scanning electronic microscopy, transmission electron microscopy, and Fourier transformation infrared spectrometry. The results show that a uniform and smooth antibacterial layer of 200 nm in thickness was formed on the surface of wool fiber by covalent bonding. The mechanical properties of the antibacterial wool fiber were improved. The antibacterial performance was found to be excellent, with antibacterial effect up to 90 % even after repeated washing. CCTS-SLS-wool possessed soft hand-feeling and good color.     

Enzymatic treatment on cotton fibers: degradation kinetics of pectin and influence of shape change on adsorption

Alkaline pectinase was one of the most effective enzymes to treat cotton as alternative agent to replace the conventional alkaline method. Removal of pectin and cutin was considered the explanation for improvement of wettability as well as water adsorption on cotton fiber. However, degradation kinetics of pectin is unclear, and the influence of fiber shape on property changes after enzymatic treatment was ignored. The main objective of this work was to reveal interactions between pectinase and cotton fiber for mechanism study. A heterogeneous catalysis kinetic equation, which is associated with Langmuir adsorption model and enzyme deactivation, was used to describe the heterogeneous catalysis. The enzymatic process conditions were optimized. Raw cotton fibers, pectinase-treated and alkali-treated fibers were characterized by impurities content determination, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscope (SEM). Mechanism of water adsorption enhancement on treated fibers was discussed. In addition to elimination of the outer impurities, flat fibers with less twist and shape changes of lumen were also obtained to ensure better accessibility and water adsorption after enzymatic treatment.     

Influence of oxygen content of kneading atmosphere on oxygen uptake and relaxation index of bread dough with various additives

The role of oxygen during mixing of bread dough was investigated using a unique air-tight mixer in which oxygen content of the atmosphere surrounding the dough was fixed at different levels ranging from 10 to 30%. Effects of the presence in bread dough composition of various O₂ consumers, such as yeast, lipoxygenase (LOX), and additional glucose oxidase (GOX) and/or soybean or horse bean flour (containing LOX), were studied in order to characterize the competition phenomena for oxygen in the different conditions. O₂ uptake by dough during mixing was followed and relaxation tests were performed on the resulting bread dough. Variation of O₂ level of the gaseous atmosphere had no rheological impact on basic bread dough (with no additional oxidative system), even though this level was found to lead to an increase of O₂ consumption by dough, especially at the beginning of mixing. The competition for O₂ consumption among yeast, LOX and GOX was decreased by kneading under a 30% O₂ atmosphere, enabling GOX to reveal its structuring effect. Finally, mixing bread dough containing GOX under O₂-enriched atmosphere enabled keeping a standard dough relaxation index, even though dough water content was increased. This opens new perspectives for improving bread softness.