Flame-resistant polyester/cotton fabrics

New experimental results are reported for the modification of 50/50 polyester/cotton blend fabrics made from bromine-free and bromine-containing polyester with a reactive flame retardant compound of high phosphorus content. Reaction of the cotton in the blend with methyl-phosphonic diamide yields modified fabrics in which flame resistance is attained without impairment of fabric hand. The level of flame resistance depends on the amount of insolubilized phosphorus in the treated fabric, but the hand is essentially unchanged even for fabrics of high phosphorus content which pass the vertical test of DOC-FF-3-71. The results of this work provide a basis for improved definitions of future approaches to the development of flame resistant polyester/cotton blend fabrics.     

Colour constancy of vat prints on cotton fabrics

Colour constancy of prints with vat dyes on cotton fabrics was investigated by computing the CMCCON02 colour inconstancy index with the key element CAT02 for chromatic adaptation transform. The results show that the highest changes in colour appearance can be expected when the average daylight is replaced with fluorescent light. If D65 daylight is replaced with some other type of daylight, such as D50 or D55, only minor colour deviations occur which do not substantially change the colour appearance of the prints. The analysis of the influence of the lightness and chromaticity of prints shows that the chromaticity of the samples significantly affects their colour constancy. The change of appearance of the prints with lower chroma because of changed illumination conditions is less probable. The influence of a dye blend composition was also investigated. On average, multi‐coloured dye blends have proved to be more colour constant.     

Durable antimicrobial finish of cotton fabrics

Cotton fabrics were treated with Biopag, which does not have any functional groups that are reactive toward cellulose, using crosslinking agents or a binder, for the purpose of imparting a durable antimicrobial finish. In this respect, it was found that the crosslinking agents were more effective than the binder. It was confirmed by FT‐IR that the characteristic split peaks of Biopag were still seen even after repeated launderings. The crosslinking agents deteriorated the whiteness and tensile strength of the Biopag‐treated cotton fabrics, while the wrinkle recovery angles (WRAs) were significantly improved. The one‐step padding of Biopag and the crosslinking agent was found to be superior to the two‐step padding method in which Biopag padding was followed by padding of crosslinking agent in respect of WRA, whereas the whiteness and tensile strength were vice versa. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

Dry action of Trichoderma reesei cellulases on cotton fabrics

Following treatment with Trichoderma reesei cellulases, the mechanical properties of cotton fabrics were measured to assess the effect of adsorbed enzymes. The ability of adsorbed cellulases to act as anchors for further wet finishing processes was studied. Dried fabric samples, after 105 days under usual storage conditions, showed neither significant strength loss, nor any changes in the degree of polymerisation. After five months of storage, the enzymes were still found to be active. The adsorption of T reesei cellulases produced an increase in staining levels after dyeing with an acid dye, but washing fastness was poor. Washing with soap under alkaline conditions removed proteins almost completely. Adsorption of T reesei cellulases is reversible and desorption increases from pH 5 to pH 10. Because of the protein desorption under usual alkaline washing conditions, no practical application of adsorbed cellulases for further finishing processes is suggested and more work is required.     

Surface treatment of cotton fabrics with chitosan

Antibacterial activities of cotton and polyester/cotton fabrics treated with chitosan or chitosan/DMDHEU have been investigated. The washing durability properties of the aforementioned fabrics were also studied. Another group of fabric samples produced from mature and immature cotton fibres were dyed with reactive dyes and the colour yields and colour differences of the dyed fabrics assessed. The surfaces of the treated and untreated cotton fabrics were observed by scanning electron microscopy to compare the morphology.     

Effect of chemical modification of cotton fabrics on dyeing properties

The presented research deals with modifying the chemical structure of the cellulosic cotton fabrics by introducing amino groups as new active centers. The properties of the resulting aminated cotton, dimethylaminoethyl (DMAE)‐cotton, are evaluated and discussed by studying the dyeability, light fastness characteristics, and fading kinetics. The goal of this study was achieved. The modification succeeded in saving energy by decreasing both the dyeing time and temperature, and the dyeability and light fastness characteristics were improved. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1897–1903, 2002     

Influence of pregrafting cotton fabrics on kinetics of DMEU finishing

Cotton fabrics were pregrafted with a mixture of N-methylolacrylamide and methacrylic acid at mixing molar ratio of 4/6. The influence of pregrafting on the kinetics of finishing with 1,3-dimethylolethylene urea was studied. The results shows that pregrafting can increase the rate constants. Values of E_a ΔH^*, ΔS^*, and ΔG^* suggest that the pregrafting of cotton fabric not only affects the reaction action state, but also is beneficial for the reaction between cellulose and the finishing agent. © 1996 John Wiley & Sons, Inc.     

Modeling the deposition of fluorescent whitening agents on cotton fabrics

The adsorption of two widely used fluorescent whitening agents (FWAs) on unbrightened cotton fabrics has been investigated as a function of temperature, hardness of the wash liquor, initial concentration of FWA in solution, and fabric to wash liquor ratio. Sorption efficiencies of FWAs have been studied using a UV spectrophotometry technique. A mechanistic model has been developed to describe the dissolution process of FWAs, convective mass transport into the fabrics, diffusion in the stagnant layer to the fabrics' surface, and adsorption of FWAs on cotton fabrics. Dual porosity of the fabrics (inter‐yarn and intra‐yarn porosity) has been considered by allowing two different regions (outer and inner areas of the cotton fabrics) where FWAs molecules can diffuse and adsorb. Good agreement between experimental and predicted whiteness benefit by the proposed mathematical model has been observed for the range of variables considered. © The Authors AIChE Journal published by Wiley Periodicals, Inc. on behalf of 2017 American Institute of Chemical Engineers AIChE J, 64: 1305–1316, 2018     

Preventing discoloration of squalene-soiled cotton fabrics with antioxidants

Removal of discoloration caused by aged oily soils is difficult because oily soils undergo autoxidation, which results in polymerization and formation of chromophores. Use of antioxidants and a reducing agent was investigated for their impact on appearance retention and soil removal. The effect of a reducing agent, sodium dithionite, on the removal of aged squalene from cotton fabrics was studied as a pretreatment to laundering, which enhanced the removal of squalene as well as whiteness restoration. Increases in treatment concentration and time increased color removal. However, no significant increase was found in oil removal, suggesting that the role of the reducing agent is mainly a reductive bleaching action. Thus, the color will probably reverse by oxidation over time making this approach a not-so-promising laundry treatment. As a method of preventing discoloration of oily soiled textile materials, antioxidants Irganox^® 1010, t-butylhydroxyanisole and α-tocopherol were examined; they were found to be effective antioxidants for this purpose by preventing the discoloration of squalene upon aging. With Irganox^® 1010, this prevention occurred without decreasing the detergency of the oil. Most importantly, these antioxidants either did not stain the substrate or showed very low levels of staining upon usage. The biggest barrier to applying antioxidants on textiles is their hydrophobic nature. A search for water-soluble antioxidants with nonstaining and good oxidation inhibiting properties is necessary.     

Photocatalytic functional cotton fabrics containing benzophenone chromophoric groups

In preparation of self‐decontamination clothing materials in high reactivities against toxic agents, photoactive benzophenone chromophoric groups were incorporated into cotton fabrics. The cotton fabrics were treated by using 4‐hydroxybenzophenone as a reagent, 1,2,3,4,‐butanetetra carboxylic acid (BTCA) as a crosslinker, and sodium hypophosphite as a catalyst. The fabric treatment was conducted by a pad‐dry‐cure method. The benzophenone chromophoric group incorporated cotton fabrics were characterized by FTIR, SEM, TGA, and so on. The results confirmed the expected structures of the benzophenone chromophoric group modified and BTCA crosslinked cotton fabrics. The treated cotton fabrics demonstrated radical reactivities and antibacterial activity under UV irradiation. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Thermoanalytical characteristics of durable press treated cotton fabrics

Thermoanalytical characteristics of chemically treated cotton fabric often appear similar to those of untreated cotton. The overwhelming amount of cotton cellulose versus the small quantities of finishing chemicals present can mask many features contributed by reactant. The current work is an initial attempt to detect and differentiate among a variety of durable press finishes. They include three N-methylol reactants, and four polycarboxylic acids with two alkali metal salts of phosphorus-containing acids used to catalyze their reaction with cellulose. Differential scanning calorimetric and thermogravimetric techniques were employed under dynamic nitrogen conditions. Changes in residue, rate of weight loss, peak intensity, and peak temperature were observed and varied with reactant, catalyst used, and washing. The ability to distinguish among polycarboxylic acids, catalysts, and/or other formaldehyde-based reactants is of value to the textile chemist. With these preliminary results, we may soon offer a new means of finish identification. © 1993 John Wiley & Sons, Inc.

1 This article is a US Goverment work and, as such, is in the public domain in the United States of America.

     

Antimicrobial activity of cotton fabrics containing immobilized enzymes

Immobilization of α‐amylase, alkaline pectinase, and laccase enzymes onto ester‐crosslinked as well as Cu‐chelated cotton fabrics were carried out. Factors affecting the extent of enzyme‐loading and retention activities of immobilized enzymes were studied. Proper conditions for attaining higher extent of fixation along with better retained activity were studied. The degree of antimicrobial activity of treated fabric samples against gram‐negative and gram‐positive bacteria, filamentous, and nonfilamentous fungi were evaluated. The antimicrobial activity is determined by the type of substrate, i.e., Cu‐chelated > ester‐crosslinked and activated cotton substrate, and the nature of immobilized enzyme, i.e., alkaline pectinase > α‐amylase > laccase, irrespective of the used microorganism. The antimicrobial activities of the treated fabrics are completely maintained after laundering at least ten consecutive wash cycles. Further consecutive wash cycles, i.e., 20 or 30 cycles, has practically negative impact on the retained antimicrobial efficacy. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1754–1761, 2007     

Plasma-induced adhesion improvement of cotton/polypropylene-laminated fabrics

In this study, improvement in the adhesion strength of plasma-pretreated and laminated cotton/polypropylene (PP) fabrics using acrylic-based adhesive was investigated. Low-temperature, low-pressure oxygen plasma was utilized for surface modification of cotton/PP-laminated fabrics. Water absorption time was measured on plasma-treated cotton fabrics at different plasma power and treatment time conditions. The plasma conditions providing the fastest liquid absorption on the surface were selected and applied during plasma pretreatments. Surface wettability increased with increasing plasma power and plasma exposure time. Plasma-induced surface morphology changes were observed via Scanning Electron Microscope (SEM) images. X-ray Photoelectron Spectroscopy (XPS) analysis showed that oxygen content on the surface increased with plasma treatment, which contributed to the surface polarity and hydrophilicity. Peel bond strength results of untreated and plasma-treated samples were analyzed to determine the effect of plasma pretreatment process. Adhesion strength values of laminated samples, before washing and after 40 wash cycles, were determined by peel bond strength tests. Before washing, adhesion strength of plasma pre-treated, laminated samples was 28–60% higher than that of untreated laminated fabrics. After 40 wash cycles, adhesion strength of plasma pre-treated and laminated samples was about 40–69% higher than the untreated laminated fabrics. Peel bond strength values decreased with the increased number of wash cycles. Plasma pretreatment enhanced both the adhesion strength and washing resistance of laminated samples.     

Molecular weight effect on antimicrobial activity of chitosan treated cotton fabrics

The effect of the molecular weight of chitosan on antimicrobial activity was investigated using three chitosans of different molecular weights [1800 (water soluble), 100,000, and 210,000] and similar degrees of deacetylation (86–89%). Cotton fabrics were treated with chitosan by the pad–dry–cure method. The molecular weight dependence of the antimicrobial activity of chitosan was more pronounced at a low treatment concentration. Chitosans with molecular weight of 100,000 and 210,000 effectively inhibited Staphylococcus aureus at a 0.5% treatment concentration. Chitosan with a molecular weight of 1800 was effective against S. aureus at a 1.0% treatment concentration. Escherichia coli was effectively inhibited by chitosan with a molecular weight of 210,000 at a 0.3% treatment concentration and by chitosans with a molecular weight of 1800 and 100,000 at a 1.0% treatment concentration. Proteus vulgaris was effectively inhibited by chitosans with molecular weight of 100,000 and 210,000 at a 0.3% treatment concentration and by chitosan with a molecular weight of 1800 at a 0.5% treatment concentration. None of the chitosans significantly inhibited Klebsiella pneumoniae and Pseudomonas aeruginosa below a 1.0% treatment concentration. Chitosans with high molecular weights were more effective in inhibiting bacterial growth than chitosans with low molecular weights. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2495–2501, 2001     

水性聚氨酯棉织物抗皱整理工艺探讨

针对纯棉织物急、缓弹回复角、断强保留率、白度和增重率几项指标,对合成的封闭型水性聚氨酯进行了抗皱整理工艺的研究。通过单因素和正交实验探讨了水性聚氨酯种类及用量、催化剂种类及用量、焙烘温度和时间对抗皱效果的影响,确定了水性聚氨酯抗皱整理最佳工艺条件。     

Antimicrobial activity of cotton fabrics treated with curcumin

Curcumin, a yellow pigment known to have various biological activities, was applied onto cotton as an antimicrobial agent. Curcumin could provide both color and antimicrobial activity to cotton and can be dyed using a batch or continuous process. However, curcumin and cotton have low affinity and therefore the ability of curcumin to impart durable antimicrobial activity on cotton needs to be studied. In this research, the ability of curcumin dyed onto cotton fabrics to inhibit the growth of Escherichia coli and Staphylococcus aureus was studied. Relationships that can predict the rate of inhibition based on the curcumin concentration or shade depth (K/S values) were developed without the need for an antimicrobial test. Durability of antimicrobial activity to laundering and to light was also studied. Curcumin was more effective in inhibiting S. aureus than E. coli. The reduction of bacteria and durability of antimicrobial activity of curcumin to laundering was inferior on cotton fabrics compared with wool. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Development of conductive cotton fabrics for heating devices

Recent developments in the area of textiles to make fabrics more functional have led to synthesizing “intelligent fabrics.” This can be achieved by making the fabrics electrically conducting. In the present study it is reported that the cotton fabrics, when impregnated with polypyrrole, achieve enhanced level of conduction. The method of diffusion of pyrrole, followed by polymerization using iron chloride as oxidant, was used. The different levels of conduction were achieved by varying the contents of monomer in the bath from 0.01 to 0.1M during the synthesis. The conductivity could be enhanced from the initial value of 10^?12 to 10¹ S/cm. It is shown that when a fixed voltage is applied to such a modified piece of cloth, the heat generated is up to 1000 W/m² depending on the percentage of pyrrole present. Such fabrics can be used as heating pads and integrated into the apparel to keep the wearer warm enough using a portable 9.0‐V battery. Being flexible and breathable, such fabrics have better comfort properties (compared with conventional heating pads). It can find applications in dresses for army personnel and old‐age patients. Such conductive fabrics can also find applications in many areas such as electromagnetic interference shielding, gas sensors, and temperature indicators. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4690–4695, 2006     

荧光增白剂对纯棉织物洗涤效果的影响

采用添加不同种类和用量荧光增白剂的标准洗衣液洗涤不同颜色纯棉织物,对比分析洗涤后织物的L*,a*,b*和C*值,反射率曲线以及目视评价结果,得到荧光增白剂对不同颜色纯棉织物的影响效果。结果表明,荧光增白剂可使增白布更白,漂白和米白布明显变亮白,浅蓝和粉红布样更加艳丽,浅灰和浅黄布样泛白或变浅,使卡其布样明显泛白,对大红、深蓝、黑色等深色纯棉织物无明显影响。