Modification Of Wool Research Articles

Cover Image, Volume 50, Issue 16

Journal of Polymer Science Part A: Polymer ChemistryVolume 50, Issue 16 p. i-ii Cover Image Cover Image, Volume 50, Issue 16 First published: 06 July 2012 https://doi.org/10.1002/pola.26228AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Graphical Abstract The cover image shows wool fiber modified by amphiphilic graft terpolymers to improve dyeability [green: hydrophobic segments originating from poly(methacrylate)s stems; blue: hydrophilic segments originating from polyethers; yellow: reactive segments for connecting with wool]. In the work by Mitsuhiro Hirata, Takeshi Watanabe, Bungo Ochiai, and Takeshi Endo on page 3259, the amphiphilic graft terpolymers were synthesized by the graft-onto reaction of monoamino-terminated polyethers to poly(methacrylate)s bearing five-membered cyclic dithocarbonate moieties. The modification of wool was conducted via the disulfide exchange reaction between disulfide linkages in wool and the thiol groups in the graft terpolymers. The dyeability toward carthamin, a natural red pigment from safflower, was improved by the modification. Volume50, Issue1615 August 2012Pages i-ii RelatedInformation

Synthesis of graft terpolymers by addition reaction of amino-terminated polyether to poly(methacrylate)s bearing five-membered cyclic dithiocarbonate moieties and application of the graft terpolymers as modifiers for wool

Graft terpolymers bearing polyether side chains and poly(methacrylate) stems were synthesized by the graft-onto reaction of monoamino-terminated poly(PO9-co-EO1) to poly{[5-(methacryloyloxy)methyl-1,3-oxathiolane-2-thione]-co-n-butyl methacrylate} [poly(DTCMMA-co-BuMA)]. The grafting reaction proceeded via the nucleophilic addition of the terminal amino groups to the five-membered cyclic dithiocarbonate moieties giving thiol moieties, although the grafting efficiency was low (9–34%) due to the steric hindrance of the side chains. The Tg values of the poly{[DTCMMA-graft-poly(PO9-co-EO1)]-co-BuMA} ranged 27–47 °C, depending on the amounts of flexible poly(PO9-co-EO1) chains introduced lowering the Tg values. Poly{[DTCMMA-graft-poly(PO9-co-EO1)]-co-BuMA}s bearing thiol groups were applied for the modification of wool via the disulfide exchange reaction. The modified wool had better dye ability toward a pigment from safflower than the original wool owing to the hydrophilic nature of poly{[DTCMMA-graft-poly(PO9-co-EO1)]-co-BuMA} introduced. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012

Surface modification of wool with protease extracted polypeptides

Polypeptides were extracted from wool protein fibres using the serine type protease Esperase 8.0L (EC 3.4.21.62), a subtilisin from Bacillus sp., in a reducing solution. The extracted polypeptides, in aqueous liquor, were then applied to modify the fibre surface of wool fabric with or without additional protease. The treated wool fabric was subsequently treated with the cross-linking agent, glycerol diglycidyl ether, and then underwent a curing process to affix the polypeptide to the fibre. The resulting knitted fabric showed a very high level of shrink-resistance to machine washing, without excessive fibre damage. Shrinkage of 1-2% could be achieved after 5 times 5A washes with minimal (<1%) weight loss due to washing and a burst strength of 317 kPa.

Application of sodium benzoyl thiosulphate from aqueous solution to wool and its effect on substantivity of disperse dyes. Part 2: modification of wool with sodium benzoyl thiosulphate

Sodium benzoyl thiosulphate was applied to wool fabric from aqueous solutions in order to covalently bind benzoyl groups to the fibre and thus impart disperse dye substantivity to the modified wool. The modified wool fabric was dyed with a selected model disperse dye, CI Disperse Blue 56, and the wash fastness properties of the dyeings assessed.

Natural wool/cellulose acetate blends regenerated from the ionic liquid 1-butyl-3-methylimidazolium chloride

Dissolution and blending one of the most commonly used natural polymers, i.e., wool using a green solvent ionic liquid is described. The cleaned natural wool from merino sheep was directly dissolved and regenerated from 1-butyl-3-methylimidazolium chloride (BMIMCl) without any modifications. BMIMCl was subsequently used to develop wool/cellulose acetate (CA) blends. Blending modification of wool in this IL green solvent led to significant increase in glass transition temperature ( T g) and thermal stability compared to the pure components. It was found that there exist strong intermolecular hydrogen bonding interactions between regenerated wool and CA. Moreover homogeneous surface morphology was observed in the blends with higher CA concentrations. At the final stage of the blending process, the IL solvent was recycled completely. This work presents a green processing route for development of novel natural wool blended materials.

Multifunctional modification of wool using an enzymatic process in aqueous–organic media

An enzymatic method using laccases for grafting the water insoluble phenolic compound lauryl gallate on wool fabric was developed. To find the compromise conditions at which the substrate is soluble while the enzyme remains active, the reaction was carried out in an 80/20 (v/v, %) aqueous–ethanol mixture, where the enzyme retains 75–80% of its activity. The enzymatic coating of wool with lauryl gallate provided in a one-step process a multifunctional textile material with antioxidant, antibacterial and water repellent properties.

Studies on antibacterial dressings obtained by fluorinated post-discharge plasma

Surface modification of wool, polyamide 6 and cotton fabrics was investigated with an Ar–CF 4 post-discharge plasma. The radical F, as determined by optical emission spectroscopy, is considered to be the main active species acting on the fabrics and producing different effects as a function of the textile substrate. Fluorination of the surface is achieved on the three materials studied, but only wool and polyamide 6 fluorinated surfaces become hydrophobic at long treatment times, and show antibacterial properties. The treatment conditions used are mild enough so as not to alter surface topography, as confirmed by scanning electron and atomic force microscopy.

Synthesis of polymeric peroxides and their use in finishing treatment of textile materials

A polymeric peroxide was prepared by the reaction of α-chloroethyl tert-butyl peroxide with polyvinyl alcohol. Procedures for modification of wool and polycaproamide textile materials with this peroxide were suggested.

Novel microbial-mediated modifications of wool

A total of 158 microbial strains, previously isolated from raw wool samples of Portuguese Merino breed of sheep, were screened for extracellular protease activity. The 12 isolates with the highest overall activity were further tested via incubation in nutrient broth, and assaying of cell-free supernatants using casein as substrate protein. The cell-free supernatants of the three isolates exhibiting the best performance were finally tested on knitted wool using bursting strength and area shrinkage as quantitative parameters, and microstructure using scanning electron microscopy as qualitative parameter, to conclude on their putative role upon the fiber features. The aforementioned three isolates produced lower weight loss and area shrinkage than those brought about by a commercial reference enzyme under similar operating conditions, without significantly loosing bursting strength.

Research and application of biotechnology in textile industries in China

Textile industry is a conventional and pillar industry in China, which possesses a considerable proportion of the national economy. In recent years, special attention has been paid to the application of biotechnology in textile industries in China. As an interdiscipline between natural science and engineering science, textile biotechnology has much effect on China's textile industry. This paper summarizes current developments and highlights those areas where biotechnology might play an increasingly important role in China's textile industry as follows: (1) Development of new types of textile fibers and polymers, such as Bt cotton naturally colored cotton, colored silk and silk gene-sequence, spider silk non-wovens, chitin fiber and chitosan derivatives, etc. (2) Application of enzyme technology in textile wet processing, such as alkaline pectinase, PVA-degrading enzyme, cutinase and catalase used for cotton preparation, neutral cellulase for denim washing, transglutaminase for wool modification, protease for silk degumming as well as pectinase and hemicellulases for retting of bast fibers. (3) Treatment of textile effluents with biotechnology.

XPS analysis of down stream plasma treated wool: Influence of the nature of the gas on the surface modification of wool

A microwave plasma treatment in a down stream configuration was used to modify the natural hydrophobocity of untreated wool fibers. This property is a consequence of the presence of a Fatty acid monolayer (F-layer) on the outermost part of the fiber surface. The wool fibers treated with plasma were analyzed by means of X-ray photoelectron spectroscopy (XPS) without previous exposure to the air. Experiments have been carried out with air, water vapor, oxygen and nitrogen as plasma gas. The “in situ” analysis of the treated samples has permitted to differentiate between the plasma effects and those other linked to the exposure of the fibers to the air after their treatment. The results have evidenced the effects induced by the different active species generated by plasma from the different components of the air. In general, the intensity of C C peaks decreases and that of the C O, C O and O C O increases when using a gas containing oxygen species. Simultaneously, the intensity of the S S groups decreases and that of the sulphonate (SO 3 −) increases. Other changes are also detected in the intensity of the N 1s level. The extent and characteristics of the oxidation and functionalisation of the hydrocarbon chains of the F-layer depend on the nature of gas. Thus, whereas treatments with plasmas of air and water vapor strongly affect the hydrocarbon chains of the F-layer, oxygen is less effective in the oxidation process. It has been also noted that the active species formed in the nitrogen plasma do not induce any significant change in the surface composition of the wool fibers.

Enzymatic modification of wool with tyrosinase and peroxidase

The capabilities of tyrosinase and peroxidase to activate tyrosine residues of wool fibres and to catalyze crosslink formation between peptides derived from a wool protein hydrolyzate were investigated. Peroxidases were able to catalyse oxidation of wool fibres corresponding to 35–40% of the tyrosine residues located on the wool surface or 2% of the tyrosine residues in the wool fibre. Similar fibre surface modification was detected with tyrosinase and a fungal peroxidase using x-ray photoelectron spectroscopy. Tyrosinase did not show detectable activation of fibres measured as oxygen consumption. Tyrosinase was, however, able to crosslink peptides of 3–10 kDa derived from enzymatically hydrolysed wool fibres. Surprisingly, no crosslinking was detected with peroxidase.

Surface modification and low temperature dyeing properties of wool treated by UV radiation

The surface modification and dyeing properties of wool treated by UV radiation have been investigated. Wool samples were exposed to UV radiation for 60 min and the surface modification of the wool fibre was investigated by X‐ray photoelectron spectroscopy. The chemical change caused by the UV treatment was identified as surface oxidation of cystine (disulphide bonds) and thereby induced changes in the dyeing properties of the wool. The dyeability of UV‐treated and untreated wool samples was determined at temperatures of 45, 50, 55 and 60 °C using CI Acid Blue 7. The UV‐treated wool samples showed greater levels of dye uptake compared with those of the untreated samples. The adsorption behaviour and diffusion coefficients were also studied. The dyeing properties of wool were enhanced by UV radiation due to the increased diffusion coefficient of the dyes in the treated wool fibres.

Enzyme processing of textiles in reverse micellar solution

Scouring of cotton using pectinase enzyme, bioscouring, in reverse micellar system was studied. The effectiveness of bioscouring was evaluated by measuring weight loss of cotton, analyzing pectin and cotton wax remaining and by wetness testing. Pectinase enzyme showed excellent activity even in organic media, and the effectiveness of scouring was equivalent or better than that achieved by conventional alkaline process or bioscouring in aqueous media. Enzymatic modification of wool using protease enzyme in the same system was also studied. It has found that felting property and tensile strength of wool fabrics treated by protease in reverse micellar system were superior to those in aqueous media. Possibilities of utilization of the same system for the subsequent textile dyeing process were also investigated. It was found that cotton and polyester fabrics were dyed satisfactorily by reverse micellar system compared to conventional aqueous system.

P-Mannich Reaction on Wool Fibre for Activation in Dyeing

Chemical modification of wool by means of dimethyl phoaphitc and D-glucose results in an increase in dye pickup, while colour and light fastness properties did not decrease, in fact some features bccpme more favourable. Our invesigations showed that increase in fibre diameter occurred. which could rise the rate of dye penetration. Amino acid analysis of the treated wool sample h w e d a decrease in lysine and arginim content, which allows of supposing covalent bond formation betweecl dimcthyl phosphite, D-glucose and the amino and guanidino groups of wool.

Application of the Maillard, Strecker and modified Strecker (P–Mannich) reactions for the chemical modifications of wool

The application of the Maillard, Strecker and modified Strecker reactions in the chemical modification of wool are described. A practical method for improving reactive or acid dye pick–up under milder conditions of wool dyeing was the aim of the present work. This can be achieved by means of chemical bonding of selected carbohydrates with wool.

Modification of Wool-fibre Properties by Phosphorylative Treatment

A study is reported on the modification of wool under anhydrous conditions with various phosphorylation treatments. The results obtained confirm that the use of phosphorus trichloride in an anhydrous solvent imparts a high phosphorus loading to wool and modifies the surface properties without whole-fibre degradation.

Investigation of the Alkaline Modification of Wool Using New Analytical Methods for the Determination of Degradation

In order to meet the requirements for brilliant colours and high wet fastness, the cotton component of wool/cotton blends is often dyed with reactive dyes under strongly alkaline conditions. A modified enzymatic method has been used to determine dehydroalanine residues formed in wool during commercial dyeing treatments. Reaction mechanisms of cystine degradation have been studied on the basis of the amounts of dehydroalanine present. Hydrogen sulphide could be determined quantitatively in wool and in dyebaths using an improved method that minimises further cystine degradation and hydrogen sulphide oxidation.

The Modification of Wool with Reactive Hydrophobes

A series of seven reactive hydrophobic compounds was synthesised and authenticated. Aqueous dispersions of these compounds were prepared by milling and applied to wool by pad–dry–steam and exhaustion procedures. The extent of fixation achieved was assessed by determining the weight gain of the treated wools. Treated wool fabric was transfer printed with disperse dye papers and the disperse dye affinity was assessed both by dye yield (K/S) measurements and by determining the

Wool Modification by Dialdehyde Starch Treatment

Merino wool was treated in variable pH, temperature, and bath concentration conditions with dialdehyde starch. The fastness to acid dyes, solubility in urea bisulfite, alkalies, and acids, as well as mechanical properties and aminoacid composition were determined. The results show that the treatment increases the resistance towards chemical agents, while the dyeing and mechanical properties are unchanged or slightly reduced. The reaction sites seem to be lysine, histidine, and tyrosine on the basis of amino acid analysis.