The allylamine grafting on the plasma pre-treated polyester nonwoven fabric: Preparation, characterization and utilization

This article describes the novel possibility of the polyester (polyethylene terephthalate) surface modification by plasma treatment. Moreover, this modified polyester could be component for the composite material (with hyaluronic acid) used in the wound healing. In this study, the experimental methods: FT-IR spectroscopy, the contact angle measurement, X-ray photoelectron spectroscopy and scanning electron microscopy were used for the surface modified polyester characterisation.     

Characterization of conductive polypyrrole coated wool yarns

Wool yarns were coated with conducting polypyrrole by chemical synthesis methods. Polymerization of pyrrole was carried out in the presence of wool yarn at various concentrations of the monomer and dopant anion. The changes in tensile, moisture absorption, and electrical properties of the yarn upon coating with conductive polypyrrole are presented. Coating the wool yarns with conductive polypyrrole resulted in higher tenacity, higher breaking strain, and lower initial modulus. The changes in tensile properties are attributed to the changes in surface morphology due to the coating and reinforcing effect of conductive polypyrrole. The thickness of the coating increased with the concentration of p-toluene sulfonic acid, which in turn caused a reduction in the moisture regain of the wool yarn. Reducing the synthesis temperature and replacing p-toluenesulfonic acid by anthraquinone sulfonic acid resulted in a large reduction in the resistance of the yarn.     

A study of metal oxide on antimicrobial effect of plasma pre-treated cotton fabric

Cotton, a natural fibre that consists of cellulose, is highly popular because it is sweat-absorbing and comfortable to wear. However, cotton fabrics provide an excellent environment for microorganisms to grow, owing to their ability to retain moisture. Therefore, numerous chemicals have been used to enhance anti-microbial activity of cotton textiles. This paper reports results of use of silver oxide (Ag₂O) or zinc oxide (ZnO) as a catalyst in the antimicrobial formulation (halogenated phenoxy compound (Microfresh, MF)) and a binder (Microban, MB) for improved treatment of cotton fabrics and minimisation of side effects of the treatment. In addition, from the morphological study, plasma technology was employed to roughen the surface of the materials to improve loading of metal oxides on the surface. Moreover, the characteristic infra-red bands related to plasma-treated cotton produced results different from untreated fabric, implying plasma treatment can improve hydrophilicity of the fabric. Mechanical strength of the specimens was also increased by plasma treatment. Meanwhile, the research showed that the control fabric slightly inhibited the growth of S. aureus because of the bleach residues on fabric surface. On the other hand, anti-bacterial activity of MF-MB-treated specimen, especially in the presence of metal oxide catalyst, was enhanced, providing a slightly larger zone of inhibition. Moreover, plasma gas contains reactive oxygen species that can enter the cell, eventually causing its death. The hydrophilic nature of carbonyl groups present in oxygen plasma pre-treated specimens also increased the anti-microbial activity after treatment with MF-MB.     

Effect of low temperature plasma treatment on wool fabric properties

Low temperature plasma (LTP) treatment was applied to wool fabric with the use of a non-polymerizing gas, namely oxygen. After the LTP treatment, the fabric properties including low-stress mechanical properties, air permeability and thermal properties, were evaluated. The low-stress mechanical properties were evaluated by means of Kawabata Evaluation System Fabric (KES-F) revealing that the tensile, shearing, bending, compression and surface properties were altered after the LTP treatment. The changes in these properties are believed to be related closely to the inter-fiber and inter-yarn frictional force induced by the LTP. The decrease in the air permeability of the LTP-treated wool fabric was found to be probably due to the plasma action effect on increasing in the fabric thickness and a change in fabric surface morphology. The change in the thermal properties of the LTP-treated wool fabric was in good agreement with the above findings and can be attributed to the amount of air trapped between the yarns and fibers. This study suggested that the LTP treatment can influence the final properties of the wool fabric.     

Optimum condition of ink-jet printing for wool fabric

This paper is aimed at studying the optimum content of pre-treatment print paste used for ink-jet printing of wool fabric. Optimum condition of ink-jet printing with respect to the content of pre-treatment print paste and steaming time has been successfully developed through the orthogonal analysis. The parameters of the pre-treatment print paste including sodium alginate, urea and ammonium tartrate, as well as the post-treatment of steaming time right after ink-jet printing have been investigated. The optimum content of the pre-treatment print paste and the proper condition of post-treatment has been developed to achieve higher colour yield for cyan, yellow, magenta and black color (CYMK). The results of the highest colour yield obtained confirm that steaming time is the most dominating factor when compared with the other factors.     

Functional modification of wool fabric by thiol-epoxy click chemistry

The paper reports modification and characterization of wool fabrics achieved through thiol-epoxy click chemistry. A pretreatment with tris (2-carboxyethyl) phosphine (TCEP) as an effective reducing agent was carried out to produce thiol groups on wool surface. Glycidyl trimethyl ammonium chloride (GTAC) was later covalently bonded with wool fibers via thiol-epoxy reaction. The reaction was confirmed by SEM, FTIR, Raman and TG analysis. Antibacterial activity, antistatic property, hydrophilicity and dyeability of treated wool fabric were assessed. The results demonstrated that TCEP-GTAC treatment can endow wool fabric good antibacterial and antistatic properties as well as improved hydrophilicity. Tensile strength studies indicated fiber strength loss of ~12 % on modification.     

Dimensional properties of low temperature plasma and silicone treated wool fabric

Three different silicone polymer systems, such as aminofunctional, epoxyfunctional, and hydrophilic epoxyfunctional silicone polymers, were applied onto plasma pretreated wool fabric to improve the dimensional properties. The results showed that the plasma pretreatment modified the cuticle surface of the wool fiber and increased the reactivity of wool fabric toward silicone polymers. Felting shrinkage of plasma and silicone treated wool fabric was decreased with different level depending on the applied polymer system. Fabric tear strength and hand were adversely affected by plasma treatment, but these properties were favorably restored on polymer application. Therefore, it has been concluded that the combination of plasma and silicone treatments can achieve the improved dimensional stability, and better performance properties of wool fabric. The surface smoothness appearances of treated fabrics were measured using a new evaluation system, which showed good correspondence with the results of KES-FB4 surface tester.     

Influence of pH on hygral expansion,relaxation shrinkage and extensibility of wool fabric

The standard tests for relaxation shrinkage and hygral expansion of wool fabric take no account of pH. It is shown in this work that the pH of the solution in which wool fabric is relaxed as part of the procedure for measuring dimensional properties has a significant influence on the results. At around pH 4.8, which is close to the isoelectric point of wool, the hygral expansion reaches its greatest value and drops at both lower and higher pHs. A similar relationship between pH and extensibility of wool fabric was observed. Values of relaxation shrinkage were found to be dependant on pH. The reasons for the pH dependence of dimensional properties are discussed and these include changes in wool fiber swelling, yarn crimp and polymer relaxation phenomena with changes in pH.     

Laser treatment of the wool fabric for felting shrinkage control

Laser treatment is one of the technologies which are able to eliminate all the adverse effects on the environment caused by chemical treatment commonly used in textile finishing. In this research, we investigated the use of laser treatment for the purpose of wool felting shrinkage control, and compared its effectiveness with that of the traditional chlorination treatment method. The wool fabric was exposed to an industrial laser at two different power levels and two sweep speeds. We found that upon selecting the appropriate treatment parameters, the laser treatment is effective in reducing felting shrinkage of wool fiber by its etching effects on the scales of the wool fiber as shown by the scanning electron micrographs. Too high energy exposure of the wool fiber by laser radiation causes excessive fabric strength loss. We also found that the laser-treated wool has felting shrinkage reduction similar to that treated using the traditional chlorination procedure. The laser technology presents an alternative wool processing method to replace the tradition chlorine treatment method. If this technology can be applied to wool felting-proof finishing on a commercial scale, it will significantly benefit the environment by completely elaminating the harzardous chlorine compounds currently by the industry.     

Effect of laccase on dyeing properties of polyphenol-based natural dye for wool fabric

Chemical mordants are generally used during the dyeing process, to increase the uptake of natural dyes. Traditional mordants include metal salts, such as copper, iron, aluminum, chromium, and other metal ions. Continuous developments in bio-engineering technology focus on methods that lower the impact on the environment. In this regard, enzymatic processes show great promise in textile field, due to their efficacy, mild conditions, and environment friendly nature. Laccase is a multicopper oxidoreductase that catalyzes in-situ polymerization of small phenolic monomers to form a colorful polymer. In this study, effects of laccase treatment on the dyeing properties of wool fabrics, dyed with natural dyes (turmeric, grape seed extract, and Chinese gallnut), were investigated. The dyeing properties of the dyed wool fabrics were evaluated under different conditions, including laccase stoichiometry, temperature, pH, and reaction time. The structural changes of natural dyes, due to laccase catalyst were also examined by FT-IR. The results showed that laccase greatly influenced the dyeing performance of Chinese gallnut. Moreover, dyeing effects of the samples using post-mordanting method was better than the other two methods, under the same conditions. After laccase treatment, the dyeing properties of Chinese gallnut improved. Finally, factors affecting the dyeing process with Chinese gallnut were studied and the optimized conditions were determined through single-factor experiments.     

A study of the oxygen plasma treatment on the serviceability of a wool fabric

Low temperature plasma (LTP) treatment using oxygen gas was applied to a wool fabric. The LTP treated wool fabric was tested with several methods: ASTM D5035-1995, ASTM D1424-1996, AATCC Test Method 99-2000, AATCC Test Method 61-2001 1A, AATCC Test Method 15-2002 and AATCC Test Method 8-2001 and the results were compared with the industrial requirements (ASTM D3780-02 and ASTM D4155-01). The results revealed that the LTP treated wool fabric could fulfil the industrial requirements. The results of the investigation were discussed thoroughly in this paper.     

甜菜喷施多氨液肥试验简报

１９９９年在内蒙古林西地区进行了甜菜叶面喷施“大西北”牌多元微肥、多氨液肥和多氨液肥加三苯基醋酸锡效果比较试验。结果表明,以连续两次喷施多氨液肥加本基醋酸锡效果为最好,可使甜菜根产量增加３８．１％,含糖率提高１．７８度,产糖量增加５２．１％。     

The effects of humidity on the surface modification of wool fabric through atmospheric pressure plasma jet

Current research was carried out on hydrophilic wool fibers at three different humidity conditions through atmospheric pressure plasma jet (APPJ). Samples were taken to evaluate surface microscopic morphology, surface roughness, directional friction effect (DFE), and surface chemical composition. The scanning electron microscope (SEM) and fiber friction coefficient test (FFT) results show that wetting pretreatment has significant effect on surface etching and DFE, but very limited effect on surface roughness. Allwörden reaction and X-ray photoelectron spectroscopy (XPS) results reveal that extra moisture changes C, O, N, S contents and their related characteristic functional groups, therefore increases etching degree on wool fiber surface scales. It was concluded that APPJ treatment is effective in processing wool fiber with high moisture contents.     

Preparation and photocatalytic activity of bismuth tungstate coated polyester fabric

Bi₂WO₆ particles were prepared and then coated on the polyester fabric. Surface morphology, crystal structure, and chemical structure of the Bi₂WO₆ particle coated polyester fabric were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). Photocatalytic activity was evaluated by the degradation of methylene blue (MB) under ultraviolet light irradiation. Influences of the different concentrations of Bi₂WO₆ on the deposit weight and the photocatalytic activity of the Bi₂WO₆ particle coated polyester fabric were investigated. In addition, UV protection of the Bi₂WO₆ particle coated polyester fabric was examined. The results show that Bi₂WO₆ particles are uniformly coated on the surface of the polyester fabric. The Bi₂WO₆ particles coated on the polyester fabric are irregular and are orthorhombic. In addition, the Bi₂WO₆ particle coated polyester fabric exhibits excellent photocatalytic activity and UV protection. The average degradation efficiency of MB in the presence of the Bi₂WO₆ particle on the polyester fabric coated with 10 g/l Bi₂WO₆ reaches 98.6 % after being illuminated for 7 h. Therefore, the Bi₂WO₆ particle coated polyester fabric shows excellent photocatalytic stability for dyes degradation.     

Optimization of dyeing condition for wool/cotton union fabric with direct dye using box-behnken design

Wool/cotton union fabric was dyed with a direct dye in union shade. The dyeing was performed in a single bath in relation to four factors: leveling agent (Lyogen SMKI, 0–1.5 % oww), electrolyte (sodium sulfate, 0–10 %), dyeing temperature (85–95 °C), and dyeing time (15–60 min). The dyeing was characterized by dye bath exhaustion (%), color strength (K/S value), washing fastness, and light fastness of dyed sample. Response surface analysis showed that the exhaustion of direct dye increased with electrolyte, dyeing temperature, and dyeing time while the K/S value followed a linear shape with leveling agent and dyeing temperature. An optimized recipe was formulated based on response surface strategy and numerical optimization solution.     

Tree-like structure increasing the moisture/liquid transport of textile fabric

Moisture/liquid transport in textile fabric is one of the critical factors affecting physiological comfort. Here the water transport properties of a new textile fabric, which was formed by mimicking the tree structure, are investigated. In present paper, the structure of the new material is analogized to a tree-like network. Taking the textile fabric as a porous medium, the water transport properties are investigated by combining Hagen-Posieuille law and Darcy’s law. The results show that the water transport properties of the new type of material depend on its geometrical structures, including the branching level and the diameter and length of the 0th branching level, and the structure fractal dimension. The longer the length and the more the branching level, the lower the water transport capacity. A comparison of the new textile fabric with the general fabric indicates that the new material can provide higher water transport capacity and its maximum water transport capacity approach 1.707 times higher than that of the similar general fabric.     

Mechanical properties and hand evaluation of hemp woven fabrics treated with liquid ammonia

The effects of liquid ammonia (L/A) treatment on the mechanical properties and hand of 100 % hemp woven fabrics were investigated by the KES-FB (Kawabata Evaluation System for Fabric). Tensile energy and tensile resilience were increased by the L/A treatment. Bending and shearing values such as bending rigidity, bending moment, shear stiffness, shear hysteresis of the L/A treated fabrics were lower than those of the untreated ones. Compressional linearity and compressional energy were decreased while the compressional resilience was increased by the L/A treatment. From the hand evaluation, the primary hand values as well as total hand value of the hemp fabric were markedly increased by the L/A treatment, especially when yarn number was fine. Therefore, L/A treatment was found to be an effective method of improving the flexibility and softness of hemp woven fabrics.     

Multifunctional modification of wool fabric using graphene/TiO<Subscript>2</Subscript> nanocomposite

In this study, a new finishing technique is introduced through treatment of wool fabric with graphene/TiO₂ nanocomposite. Graphene oxide/titanium dioxide nanocomposite first applied on the wool fabric by hydrolysis of titanium isopropoxide in graphene oxide suspension and then this coating chemically converted by sodium hydrosulfite to graphene/TiO₂ nanocomposite. The homogenous distribution of the graphene/TiO₂ nanocomposite on the fiber surface was confirmed by field emission scanning electron microscopy (FE-SEM), Energy-dispersive X-ray spectroscopy (EDS) and X-ray mapping. X-ray diffraction patterns proved the presence of titanium dioxide nanoparticles with a crystal size of 127 Å on the treated wool fabric. Also, the defect analysis based on X-ray photoelectron spectroscopy (XPS) established the composition of the nanocomposite. Other characteristics of treated fabrics such as antibacterial activity, photo-catalytic self-cleaning, electrical resistivity, ultraviolet (UV) blocking activity and cytotoxicity were also assessed. The treated wool fabrics possess significant antibacterial activity and photo-catalytic self-cleaning property by degradation of methylene blue under sunlight irradiation. Moreover, this process has no negative effect on cytotoxicity of the treated fabric even reduces electrical resistivity and improves UV blocking activity.     

Effects of low temperature plasma on wool and wool/nylon blend dyed fabrics

Knitted wool and wool/nylon blend dyed fabrics were treated with low temperature plasma (LTP) to achieve optimum shrink-resistance without impairing surface topography, colour or fastness to washing of the fabrics. As LTP tends to impair handle of the fabrics, both wool and wool/nylon blend fabrics were submitted to industrial softening and/or biopolymer treatments after LTP treatment, leading to hydrophilic wool and wool/nylon blend fabrics with improved shrink-resistance without any colour changes and good fastness to washing. The results obtained were compared with those obtained by an industrial shrink-resist treatment.