Pretreated Cotton Research Articles

EFFECT OF CELLULASE ENZYMES AND SWELLING AGENTS ON COLOUR STRENGTH (K/S) AND COLOURFASTNESS PROPERTY OF HANDLOOM COTTON FABRIC DYED WITH BUTEA FRONDOSA DYE

Cellulase and swelling agents are known to be effective in improving the colour strength of cotton. Nowadays, the handloom fabrics are much preferred due to development of innovative designs and their comfort in wearing Due to increased environmental awareness the use of natural dyes are much preferred in dyeing of handloom fabrics. But, khadi cotton has some major shortcomings like less dyeability. Keeping in view that the pretreatment of khadi cotton with cellulases, swelling agents and combination of cellulases and swelling agents before dyeing improves the colour strength properties, the present study was planned. The khadi cotton samples were treated with optimized conditions of enzymes and swelling agents. The optimum pH, concentration, treatment time and temperature selected for the acid cellulase enzyme treatment were 5.5, 1.5% (owf), 45 minutes and 50°C, respectively whereas in case of neutral cellulase enzyme, it was 7.5, 2.0% (owf), 70 minutes and 70°C respectively. The optimum concentration, treatment time and temperature selected for sodium hydroxide treatment were 20% w/v, 60 minutes and 60°C, respectively. In case of ethylenediamine, 80% w/v, 60 minutes and 70°C were selected as optimum concentration, treatment time and temperature, respectively. In case of zinc chloride treatment, the optimum concentration, treatment time and temperature were selected as 80% w/v, 60 minutes and 70°C. 5 g Butea frondosa dye extracted for 75 minutes gave best results on khadi cotton when dyeing was carried out for 90 minutes It was observed that out of various concentrations of mordants used with Butea frondosa dye, best shades of colour were obtained by using 0.04 g of Alum, 0.01 g of Copper sulphate, 5 g each of Baboolbark.On optimizing the method of mordanting, best results were obtained with Butea frondosa dye when samples were simultaneous mordanted and dyed with Alum, Babool bark and Alum. Pre-mordanting was selected for Copper sulphate. . It was found that for all the enzyme treated (acid and neutral cellulase) as well as swelling agents treated (Sodium hydroxide, Ethylenediamine and Zinc chloride) samples, the colour strength and colourfastness was increased in comparison to the untreated samples.

Orthogonal analysis for rechargeable antimicrobial finishing of plasma pretreated cotton

This paper reports results of an investigation of the effects of different parameters used in the antimicrobial finishing process on rechargeable antimicrobial finishing of cotton fabric after plasma pretreatment. Cotton fabric was pretreated with a mixture of nitrogen and helium plasma before coating with 5, 5-dimethylhydantoin (DMH) (i.e. plasma-pad-dry-cure) and then chlorinated with sodium hypochlorite to impart antimicrobial property. An orthogonal array testing strategy was employed for identifying optimal conditions for the coating process. After coating and chlorination, properties of finished cotton fabrics were measured in terms of concentration of chlorine, morphological properties of the surface and functional groups on the cotton fabric by Ultraviolet spectroscopy, Scanning electron microscope and Fourier Transform Infrared Spectroscopy, respectively. The results show that coating of plasma pretreated fabric with DMH, followed by chlorination, inhibits microorganisms effectively and the antimicrobial property against S. aureus is rechargeable.

Effects of reductive stripping of reactive dyes on the quality of cotton fabric

AbstractSome common problems of textile dyeing industries include uneven or faulty dyeing and formation of color patches on the fabric surface during dyeing and downstream processing of textiles materials. Such problems in the finished quality of fabric are generally tackled through a chemical stripping process which is a common practice in dyeing industries for the deep shade batches. However, reactive dyes cannot be stripped satisfactorily from cellulosic materials due to the formation of co-valent bonds between dye and fiber. This research was undertaken using 2.5% and 5% bi-hetero reactive dyes on pretreated cotton fabric and dye stripping was carried out in alkali reductive stripping process. The aim of the work was to investigate the effects of dye stripping on the quality of cotton fabric. Strength loss, weight loss, pilling resistance and absorbency of stripped fabric were calculated. Though with the increase of concentration of stripping chemicals and temperature, stripping percentages were improved; processing damage to the fabric such as losses in strength, weight and pilling resistance ratings was found. In contrast, increased fabric absorbency was found due to stripping. This is explained that during stripping, alkaline solution as an intracrystalline swelling agent is effective in loosening the crystalline region of cotton in addition to the amorphous region. Stripping agent can also attack such crystalline region. As a result, cotton fiber can release maximum number of hydroxyl groups which previously formed covalent bonds. This is the reason behind the stripped fabric having more water absorbency.

Development of antibacterial cellulosic fabric via clean impregnation of silver nanoparticles

In the present study, we investigate single bath fabrication and impregnation of silver nanoparticles (SNPs) on enzymatic pretreated cotton fabric by using starch both as reducing as well as stabilizing agent under the autoclave conditions of 103.42 kPa, 121 °C for 15 min. The SNPs were characterized using UV–visible (UV–vis) spectroscopy, zetasizer nano and transmission electron microscopy. The UV–vis absorption spectra showed typical absorption peaks at ∼420 nm corresponding to the surface plasmon resonance of SNPs. The hydrodynamic diameter of SNPs was as smaller as 20 nm with their respective zeta potential of −43.20 mV. Both scanning electron and atomic force microscopic analyses revealed that the surface of the treated cotton fabric was rougher than that of untreated fabric, and the SNPs were present on the surface of the treated fabric. Silver mapping and elemental analysis of the treated cotton fabric using energy dispersive X-ray spectroscopy confirmed the presence of SNPs in a homogeneous distribution. The textile properties of the fabric including wettability, whiteness, tensile strength and antibacterial activity were measured by using the standard methods. The SNPs impregnated cotton fabrics showed good durable antibacterial activity against Escherichia coli and Staphylococcus aureus strains.

Enhancement of antimicrobial efficacy of neem oil vapour treated cotton fabric by plasma pretreatment

This paper deals with the study on the reaction between DC air plasma treated cotton cellulose and bioactive compounds present in the neem oil vapour. Untreated cotton fabric (control) and DC air plasma pretreated cotton fabric were exposed to neem oil vapour to impart antimicrobial activity, and the process parameters such as temperature and treatment time were optimised to obtain the maximum antimicrobial activity. Gas chromatography–mass spectrometry analysis was carried out to identify the bioactive compounds present in neem oil vapour. The effect of plasma treatment in modifying the fabric surface was explored by analysing the changes in the cellulose structure, crystallinity and morphology of fabric surface using attenuated total reflection–Fourier transform infrared spectroscopy (ATR-FTIR) spectra, X-ray diffractogram and scanning electron microscopy (SEM) micrographs. The reaction between cellulose and bioactive compound present in neem oil vapour was analysed using the ATR-FTIR spectra. The change in morphology after treatment with neem oil vapour was analysed using SEM micrographs.

Novel cotton cellulose by cationisation during the mercerisation process—part 1: chemical and morphological changes

Cationisation is the modification of cotton cellulose by using quaternary ammonium compounds that block negative OH groups, thus resulting in electropositive cotton cellulose. It is an alternative method for achieving better adsorption of chemical compounds and substances, such as dyestuffs, fluorescent whitening agents, and other textile auxiliaries. The cationisation of cotton cellulose changes the surface electrical charge (electrokinetic potential) by significantly increasing its adsorption properties. The presented article investigated the chemical and morphological changes in cotton cellulose when cationised with an epihalohydrin, 2,3-epoxypropyl trimethyl ammonium chloride, after and during the mercerisation process. When comparing mercerised cotton with cationised cotton, it was concluded that cationisation during the mercerisation process using short-chain cationic compounds would result in a novel cotton cellulose that would bring a new dimension to cotton pre-treatment and finishing. The modified cotton would retain all the beneficial properties of mercerised cotton with a change of surface charge that would ensure further improvement in quality.

The influence of triangular silver nanoplates on antimicrobial activity and color of cotton fabrics pretreated with chitosan

The effect of cotton fabric pretreatment with biopolymer chitosan (CHT) on deposition of colloidal triangular silver nanoplates was studied. Also, the influence of deposited silver nanoparticles on color and antimicrobial activity of cotton fabrics was evaluated. Characterization of colloidal silver nanoparticles as well as silver nanoparticles deposited on cotton fabrics was performed using electron microscopy (TEM and FESEM), XRD analysis, atomic absorption spectroscopy, UV–Vis absorption, and reflectance spectroscopy. The cotton fabric turned from white to blue color upon deposition of triangular silver nanoplates. Antimicrobial activity of CHT pretreated cotton fabric impregnated with silver nanoparticles was tested against Gram-negative bacteria Escherichia coli, Gram-positive bacteria Staphylococcus aureus, and fungi Candida albicans. Deposited silver nanoparticles imparted excellent antimicrobial properties to cotton fabric. The standard sterilization procedure of cotton fabric for antimicrobial activity testing resulted in color change of the fabric from blue to yellow. This color change is most likely consequence of transformation of triangular silver nanoplates into nanodiscs and/or their agglomeration into spheroids.

Novel cotton cellulose by cationization during mercerization—part 2: the interface phenomena

Cationisation during the mercerisation process with an epihalohydrin results in novel cotton cellulose that gives a new dimension to cotton pre-treatment and finishing. The modified cotton retains all the beneficial properties of mercerised cotton with a change of the surface charge that ensures further quality improvement. The present paper deals with systematic investigations of the interface phenomena of cationised cotton fabric with an epihalohydrin; 2,3-epoxypropyl trimethyl ammonium chloride during and after mercerisation process. The water, ionic surfactant and dyestuff adsorption, as well as surface free energy, electrokinetic potential, isoelectric point and point of zero charge determined according to the streaming current/streaming potential method; and specific amount of surface charge of modified cotton fabrics are researched.

Fed Batch Enzymatic Hydrolysis of Cotton and Viscose Waste Fibers to Produce Ethanol

The main effort of this study was to enhance the enzymatic hydrolysis yields of cotton and viscose waste fibers via fed batch enzymatic hydrolysis. To do so, enzymes fed into slurries at two steps in fed batch mode. Also, the batch mode with the same amount of enzymes was implemented in order to be compared with the fed batch mode. The results showed that the released sugar contents from fed batch hydrolysis of cotton and viscose waste fibers were 29.0 and 32.3 g/l, respectively, but batch process released 25.0 and 30.3 g/l from cotton and viscose waste fibers, respectively, which confirms the increasing effect of fed batch process on the hydrolysis of both waste fibers. In addition, the morphological studies and enzymatic hydrolysis yields from pretreated cotton and untreated viscose waste fibers showed that alkali pretreatment for viscose waste fibers is not necessary, but has significant effect on enzymatic hydrolysis of cotton waste fibers; also, the differences in microcrystalline structures of viscose and cotton waste fibers have resulted in more enzymatic hydrolysis and then fermentation yields of viscose waste fibers. The amount of ethanol produced from cotton and viscose waste fibers were 6.9 and 8.1g/l, respectively.

Research in the Cold Pad-Batch Dyeing Process for the Cationic Cotton

Cotton fabrics pretreated with cationic polyacrylamide with quaternary ammonium group were dyed with three reactive dyes in the absence of salt by cold pad-batch dyeing method. The influences of various conditions in the dyeing process, including urea dosage, selection of alkali agent and its dosage, batching time and batching temperature on colour yield, were analyzed. Fastness properties of the dyed cotton and the dye penetration were investigated between the pretreated and untreated cotton. The results showed that the dyesK/Svalues of the pretreated cotton were improved compared with those of the untreated one, in addition, the penetration and fastness properties of the dyed cationic cotton were satisfied for application.

Ionic liquid pretreatment allows utilization of high substrate loadings in enzymatic hydrolysis of biomass to produce ethanol from cotton stalks

To enhance the enzymatic conversion of cotton stalks to glucose at high substrate loadings and subsequently to produce ethanol, biomass was subjected to ionic liquid and alkaline pretreatments. Ionic liquid, 1-ethyl-3-methylimidazolium acetate (EMIMAc), which reduced biomass crystallinity, was effective in improving the conversion of cotton stalks to glucose (82–85%) regardless of the substrate loading used during enzymatic hydrolysis. On the other hand, the glucose yield decreased from 67% to 55% with an increase in substrate loading from 3% to 15% (w/v) for the alkaline pretreated biomass. Fermentation of the glucose obtained upon enzymatic hydrolysis of the pretreated cotton stalks at the highest substrate loading (15%) resulted in ethanol yields of 74% and 46% for EMIMAc and alkaline pretreated biomass, respectively. These results highlight the advantage of EMIMAc pretreatment to maintain increased substrate loadings during enzymatic hydrolysis of lignocellulosic biomass for achieving high concentrations of products with improved yields.

Application of Poly2-Methyl Acrylate-N-Methyl Pyridinium Iodide in Salt-Free Dyeing of Reactive Dyes

Poly2-methyl acrylate-N-methyl pyridinium iodide (PMAMPI) was used as a new cationic agent to pretreat cotton with dip-pad-bake method. The pretreated cationic cotton showed electropositive in the process of dyeing with reactive dye. The thesis has studied the optimized process for salt-free dyeing conditions. In the optimized salt-free dyeing process, the cotton fabrics treated with PMAMPI showed a good performance compared to those in the process of traditional salt dyeing. The results showed that color yield and color fastness of the reactive dyes on the cationic cotton were satisfied. The three dyes with best color matching performance include reactive dark red WGE, reactive navy blue WTE and reactive golden yellow WRE.

High pressure assist-alkali pretreatment of cotton stalk and physiochemical characterization of biomass

Ground cotton stalks were pretreated with sodium hydroxide (NaOH) at concentrations of 1-4% (w/v), pressures of 30-130 kPa, durations of 15-75 min, and liquid/solid ratios of 10:1-30:1. Modeling of the high pressure assist-alkali pretreatment (HPAP) of cotton stalk was attempted. The levels of NaOH concentration, pressure, and duration were optimized using a Box-Behnken design to enhance the cellulose content of treated solid residue. The optimum pretreatment conditions were as follows: liquid/solid ratio, 20:1; pressure, 130 kPa; NaOH concentration, 3.0%; duration, 40 min. During the conditions, cellulose content of pretreated cotton stalk residue was 64.07%. The maximum cellulose conversion of 45.82% and reducing sugar yield of 0.293 g/g upon hydrolysis were obtained. Significant differences were observed in biomass composition and physiochemical characteristics between native and alkali-treated biomass. High NaOH concentration and pressure were conducive to lignin dissolution and resulted in increased cellulose content and conversion.

Effect of Enzymes and Swelling Agents on Colour Strength (K/S) Property of Khadi Cotton Fabric Dyed With Sandalwood Dye: An Eco-friendly Approach

Cellulase and swelling agents are known to be effective in improving the colour strength of cotton. Nowadays, the handloom fabrics are much preferred due to development of innovative designs and their comfort in wearing. Interests in natural dyes are also growing throughout the world and people are becoming more aware of the need for eco-friendly materials to come up and dominate the harmful synthetic dyes. But, khadi cotton has some major shortcomings like less dyeability. Keeping in view that the pretreatment of khadi cotton with cellulases, swelling agents and combination of cellulases and swelling agents before dyeing improves the colour strength properties, the present study was planned. It was found that for all the enzyme treated (acid and neutral cellulase) as well as swelling agents treated (Sodium hydroxide, Ethylenediamine and Zinc chloride) samples, the colour strength was increased in comparison to the untreated samples

Process optimization for bioscouring of cotton and lycra cotton weft knits by Box and Behnken design

The aim of the study was to discover the effect of experimental parameters like pH, enzyme dosage and temperature, on the removal of natural and accidental impurities from cotton and lycra cotton weft knitted fabrics, to make them suitable for further processing like dyeing and finishing. The optimal experimental conditions and their effects have been ascertained by response surface methodology using the Box–Behnken model. The optimum values were found to be pH 8.5, enzyme dosage 0.4% on weight of fabric and temperature 55°C. The r2 values and the F values indicate that the effect of all the parameters taken together is significant. Based on the results of the study it can be understood that the bioscouring process performed with these optimal values is suitable for pretreatment of cotton and lycra cotton weft knitted fabrics.

Production of butanol from glucose and xylose with immobilized cells of Clostridium acetobutylicum

Pretreated cotton towels were used as carriers to immobilize Clostridium acetobutylicum CGMCC 5234 cells for butanol or ABE production from glucose and xylose. Results showed that cell immobilization was a promising method to increase butanol concentration, yield and productivity regardless of the sugar sources compared with cell suspension. In this study, a high butanol concentration of 10.02 g/L with a yield of 0.20 g/g was obtained from 60 g/L xylose with 9.9 g/L residual xylose using immobilized cells compared with 8.48 g/L butanol and a yield of 0.141 g/g with 20.2 g/L residual xylose from 60 g/L xylose using suspended cells. In mixed-sugar fermentation (30 g/L glucose plus 30 g/L xylose), the immobilized cultures produced 11.1 g/L butanol with a yield of 0.190 g/g, which were 28.3% higher than with suspended cells (8.65 g/L) during which 30 g/L glucose was utilized completely using both immobilized and suspended cells while 3.46 and 13.1 g/L xylose maintained untilized for immobilized and suspended cells, respectively. Based on the results, we speculated that immobilized cells showed enhanced tolerance to butanol toxicity and the cultures preferred glucose to xylose during ABE fermentation. Moreover, the cultures showed obvious difference when grown between high initial concentrations of glucose and those of xylose. Repeated-batch fermentations from glucose with immobilized cells showed better long-term stability than from xylose. At last, the morphologies of free and immobilized cells adsorbed on pretreated cotton towels during the growth cycle were examined by SEM.

Cellulose degradation in alkaline media upon acidic pretreatment and stabilisation

The present study reports on a revised kinetic model for alkaline degradation of cellulose accounting for primary peeling/stopping reactions as well as for alkaline hydrolysis followed by secondary peeling. Oxalic acid pretreated cotton linters was utilised as the model substrate for the prehydrolysis-soda anthraquinone process. The main emphasis was investigating the effect of end-group stabilising additives such as sodium borohydride (BH), anthraquinone (AQ), and anthraquinone-2-sulphonic acid sodium salt (AQS) on the rates of the yield loss reactions. BH and AQS ensured a cellulose yield gain of 13% and 11%, respectively, compared to the reference. Both stabilisation agents decreased the content of the reducing end groups in the samples, while in the case of AQS stabilisation a 25% increase in carboxyl group content compared to the reference was also observed. As expected, the addition of end group stabilisers resulted in a significant decrease in the peeling-to-stopping rate constants ratio.

Pretreatment of cotton fabrics with polyamino carboxylic acids for salt‐free dyeing of cotton with reactive dyes

In this study, polyamino carboxylic acids have been used to improve the dyeability of cotton in a salt‐free reactive dyeing process. These polyamino carboxylic acids were prepared by partial carboxylation of polyvinylamine. Cotton fabric was pretreated with polyamino carboxylic acids and dyed with reactive dyes. The colour strengths of the dyed fabrics were evaluated by measuring the K/S values. The fastness properties (washing, rubbing and light fastness) of the dyed cotton fabrics were also measured. The pretreatment of cotton with polyamino carboxylic acids creates positive charges on the fabric surface. In this way, salt‐free reactive dyeing of cotton or dyeing with only a small amount of electrolyte is possible.

Sustainable Line of Cotton Wet Processing

Copyright: © 2013 Ibrahim DF. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Enzymes have been used for more than 50 years in the detergent, textile, food industries, to name just a few. In these industries enzymes replace chemicals and minimize water, raw material and energy consumption. Natures own technology provides us with environmentally friendly solutions and better products. Enzymes are the natural solution to industrial problems. With enzymes we can maintain the living standards we have today and at the same time preserve the environment for our children. In textile industry, enzymes are used because: they are accelerating the reactions, act only on specific substrates, operate under mild conditions, are safe and easy to control, can replace harsh chemicals and are biologically degradable [1]. In textile manufacturing the use of enzymes has a long tradition. The enzymatic desizing of cotton with α-amylases is state-of-the-art since many decades’. Moreover, cellulases, pectinases, hemicellulases, lipases and catalases are used in different cotton pre-treatment and finishing processes [2].

Modification of enzyme pretreated cotton fabric using acrylonitrile, acrylonitrile/solvent mixture and its characterization

The presented research deals with modifying the chemical structure of the bioscoured cotton fabric by acrylonitrile, acrylonitrile/acetone, and acrylonitrile/ethanol mixture. The modified cellulose was tested for weight gain, shrinkage, and wicking height and characterized by X-ray diffraction (XRD), thermal analysis (TG/DTA), elemental analysis, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and atomic force microscopy (AFM). The weight gain and shrinkage % show increased value for modified fabrics. The wicking height increases with addition of solvent. The crystallinity and thermal studies show a significant change. FTIR analysis confirms the modification by the occurrence of -C≡N stretching and -CONH2 stretching. The SEM morphology of modified fabric shows uniform swelling of fibers with better smoothness. The AFM topography reveals that the addition of solvent affects the particle size. Clear surface morphology of modified fabric reveals that this processing method can be used for preparation of medical textiles with more swelling.