X‐ray photoelectron spectroscopic study of Tencel treated with a cationic β‐cyclodextrin derivative

The interaction and the durability to laundering of a cationic β‐cyclodextrin derivative applied to Tencel were examined by x‐ray photoelectron spectroscopy (XPS). The N1(s) XPS spectra of the cationic β‐cyclodextrin treated substrates revealed the presence of the applied finish on the fibre surface and that the durability of the applied finish to hand‐wash was good. However, the cationic β‐cyclodextrin derivative showed poor durability to the ISO CO6/C2S wash protocol. Copyright © 2009 John Wiley & Sons, Ltd.     

Investigation into the removal of an easy-care crosslinking agent from cotton and the subsequent regeneration of lyocell-type fibres

Dimethylol dihydroxyethylene urea (DMDHEU)-treated cotton fabrics were treated with alkali or alternatively acid followed by alkali for increasing time periods, and their effectiveness in removing the crosslinking agent was investigated by surface (X-ray photoelectron spectroscopy) analysis, bulk analysis, crease recovery angle performance and solubility in specific solvents. The cellulose yield after the chemical stripping processes was established and the effect of the acid and alkali treatments on the degree of polymerisation of the resultant cellulose determined. Surface and bulk analyses and solubility tests suggested that alkali alone could not remove the DMDHEU from the crease-resist-treated cotton fabric. However, a sequential acid/alkali treatment effectively removed the easy-care finish from the cotton fabric and produced a commercially viable yield of cellulose.     

The bonding of a hydroxy-functional organophosphorus oligomer to nylon fabric using the formaldehyde derivatives of urea and melamine as the bonding agents

In this research, we studied the mechanism of bonding a hydroxy-functional organophosphorus oligomer (HFPO) to nylon 6.6 fabric using the formaldehyde derivatives of urea and melamine, including dimethyloldihydroxyethyleneurea (DMDHEU) and trimethylolmelamine (TMM), as the bonding agents. The nylon fabric treated with HFPO/DMDHEU or HFPO/TMM retained significant amount of phosphorus after multiple launderings. The laundering durability of the HFPO applied to nylon was probably attributed to the formation of a crosslinked polymeric network on the nylon fiber. The nylon fabric treated with HFPO/DMDHEU showed higher percent phosphorus retention than that treated with HFPO/TMM. The percent phosphorus retention of the treated nylon increased as the DMDHEU or TMM concentration was increased, and the nylon fabric's stiffness follows the same trend. The micro-scale combustion calorimetry and thermal analysis data indicate that the HFPO bound to nylon reduced peak heat release rate and heat release capacity of the nylon fabric, decreased decomposition temperature and promoted the char formation of the treated fabric. The nylon/cotton blend military fabric treated with HFPO/DMDHEO or HFPO/TMM demonstrated flame retardant performance after 10 laundering cycles.     

Crease recovery properties of cotton fabrics modified by urea resins under the effect of gamma irradiation

Cotton fabrics initially dyed with reactive dyes were treated with dimethylol dihydroxy ethylene urea (DMDHEU) resin in order to improve the crease recovery properties. As a comparison, the treatment with DMDHEU was carried out by the conventional thermal curing and gamma irradiation. The effect of treatments on the colour properties, crease recovery, mechanical and thermal properties was studied. It was found that the finishing of cotton fabrics with gamma irradiation affords better crease recovery values at low doses without affecting the colour intensity and the physical properties than the finishing by thermal curing. However, the finishing with higher doses of gamma radiation affects the mechanical properties of cotton fabrics. On the other hand, it was found that the thermal properties were improved with increasing dose.     

Comparison of different reactive organophosphorus flame retardant agents for cotton. Part II: Fabric flame resistant performance and physical properties

N-Methylol dimethylphosphonopropionamide (MDPA) is one of the most commonly used durable flame retardant agents for cotton. In our previous research, we developed a new flame retardant finishing system based on a hydroxy-functional organophosphorus oligomer (HFPO) and bonding agents, such as dimethyloldihydroxyethyleneurea (DMDHEU) and trimethylolmelamine (TMM). In this research, we compared the flame resistant performance as well as physical properties of the cotton fabric treated with these two flame retardant finishing systems. The cotton fabric treated with MDPA/TMM has a higher initial limiting oxygen index (LOI) than that of the fabric treated with HFPO/TMM due to higher nitrogen content in the system. The LOI of the cotton fabric treated with the HFPO and MDPA systems becomes identical when the treated fabric contains equal amount of phosphorus and nitrogen. The MDPA/TMM shows higher laundering durability on cotton than HFPO/TMM system. The fabric treated with HFPO/TMM and MDPA/TMM has low wrinkle resistance and low strength loss whereas the fabric stiffness significantly increases when the TMM concentration is increased.     

Comparison of different reactive organophosphorus flame retardant agents for cotton: Part I. The bonding of the flame retardant agents to cotton

N-Methylol dimethylphosphonopropionamide (MDPA), known as “Pyrovatex CP” and “Pyrovatex CP New” commercially, has been one of the most commonly used durable flame retardant agents for cotton for many years. In our previous research, we developed a flame retardant finishing system for cotton based on a hydroxy-functional organophosphorus oligomer (HFPO) in combination with a bonding agent such as trimethylolmelamine (TMM) and dimethyloldihydroxyethyleneurea (DMDHEU). In this research, we investigated the bonding of these two flame retardant finishing agents to cotton. We found that the majority of MDPA is bound to cotton by its N-methylol group and that the use of TMM as a co-reactant modestly increases the fixation of MDPA onto cotton. For HFPO, however, the use of a bonding agent is necessary to form a covalent linkage between HFPO and cotton. Both the fixation of HFPO on cotton and its laundering durability are influenced by the effectiveness and concentration of the bonding agent. The commercial product of HFPO contains approximately 33% more phosphorus than that of MDPA and the percent fixation of HFPO on cotton is also moderately higher than that of MDPA. The bonding between MDPA and cotton is significantly more resistant to hydrolysis during multiple launderings than that between HFPO and cotton. The selection of catalyst also plays a significant role in influencing the bonding of the flame retardant agents to cotton.     

Study of antimicrobial properties of cotton medical textiles treated with citric acid and dried/cured by microwaves

The purpose of this study was to examine antibacterial and antifungal activity of antibacterial finish based on Citric acid on cotton medical textiles. The ability to effectively reduce the number of gram-negative, gram-positive bacteria and yeast was evaluated, specifically comparing the antibacterial activity after two different drying/curing methods. Citric acid (CA) and diethyl–tetradecyl–[3–(trimethoxysilyl)-propyl] ammonium chloride (Quat) were used for hygiene and disinfection purposes of medical textiles in this study. It was applied by pad-dry process and its fixation to cellulose hydroxyls was enhanced either by high curing temperatures or microwaves (MW). Determination of antibacterial activity of finished products was performed according to ISO 20743:2007 standard before the washing and after the 10 washing cycles. Antibacterial activity was tested against gram-negative bacteria, Escherichia coli, gram-positive-Staphylococcus aureus and yeast, Candida albicans. Obtained results are confirming the possibility of eco-friendly CA application, for the purpose of antimicrobial finishing of cotton medical textiles. Prevention of nosocomial infections with the Citric acid is possible using both curing methods (convection and microwave) and furthermore, the treatment is durable up to 10 washing cycles. Citric acid, as one of the suitable active substances is crosslinked to the cellulose hydroxyls by the formation of ester linkages. Its antimicrobial effectiveness against the chosen microorganisms proved to be the best against S. aureus. Applied finish bath has additional crease proof effectiveness providing sufficient both antimicrobial and crease proof effectiveness, so as the durability against 10 washing cycles.     

Antimicrobial finishing of cotton textile based on water glass by sol–gel method

A low temperature and cost-effective process for antimicrobial finishing of cotton textiles has been developed by sol–gel method. The antimicrobial treatment was performed by treating cotton textile with silica sols from water glass and then with silver nitrate solution. The antimicrobial activity was determined by using E. coli as a model for Gram-negative bacteria. The results showed that the treated textile has an excellent antimicrobial effect and laundering durability. SEM analysis showed coarse surface morphological change on the water glass treated cotton textile. The residual concentration of silver ion on fabrics was informed by ICP-MS. XPS results indicated that two different states of silver were present on the surface of the antimicrobial textile.     

Permanent flame retardant finishing of textile materials by a photochemical immobilization of vinyl phosphonic acid

A new photochemical method for a permanent flame retardant finishing of textiles made of cotton (CO), polyamide (PA) and polyester (PET) is described. Using a mercury vapour UV lamp vinyl phosphonic acid (VPA) can be fixed durable to different fabrics made of CO, PA and PET in the presence of a cross-linking agent and a photo-initiator. After a home laundering cycle up to 50 wt% of the reaction mixture is retained on the fabrics and the absolute phosphorus content was found to be more than 2.0% in all investigated cases. The photochemically modified textiles showed high levels of flame retardant performance and passed a vertical flammability test for protective clothing.     

Chemical and ultrastructural changes in cotton cellulose induced by laundering and textile use

The textile industry is currently under pressure to decrease environmental load related to both the manufacture and the use of textiles. Material recycling may be one of many ways to accomplish such a decrease. Age-induced property changes in cotton textiles are important to understand in order to facilitate the recycling of cotton textiles. Consequently, this study investigates ultrastructural and chemical changes that take place in the cellulose of cotton sheets over a long time period of use and laundering. Ultrastructural changes were studied using water retention value (WRV), specific surface area measurement, scanning electron microscopy and solid state NMR spectroscopy. Chemical changes through measurement of intrinsic viscosity with and without reductive treatment, molecular mass distribution and carboxylate group content. A substantial decrease in mass average molecular mass from 1,320 to 151 kDa was observed when subjecting the sheets to more than 50 launderings. In contrast, only small differences in WRV, in fibril dimensions and crystallinity estimated using solid state NMR spectra, were observed between sheets laundered 2–4 times and more than 50 times. On one hand, the combination of minor laundering effects of WRV and solid state NMR spectra, together with the large decrease in molecular mass are positive indications for the possibility of recycling cotton into regenerated cellulosic fibres. On the other hand, results show that the specific surface area decreased, which implies that the reactivity of cotton cellulose may decrease during long-term use and laundering.     

Fabrication of AgNPs/Silane coated mechanical and washing durable hydrophobic cotton textile for self-cleaning and oil-water separation application

This study deals to develop a simple and facile two-step dip-coating method using silver nanoparticles (AgNPs) and fluorine-free silane monomer, 3-(Trimethoxysilyl) propyl methacrylate (TMSPM) for the fabrication of hydrophobic coating on cotton fabric. The anti-wetting properties, surface morphology, chemical composition, and functionality of the cotton fabric before and after modification were well characterized by contact angle measurement, scanning electron microscope (SEM), and energy-dispersive X-ray spectrum (EDX) and FT-IR respectively. The fabricated cotton fabric displays strong durability against different pH solutions, different soft/hard mechanical treatments including adhesive peeling test, abrasion with tissue paper and finger wiping, home laundering, without losing the hydrophobic property. The contact angle values (water contact angle of 148.3 ?± ?2° and oil contact angle of 0°) imply that the modified cotton has considerable hydrophobic/oleophilic properties. Additionally, the modified hydrophobic/oleophilic cotton fabric exhibits self-cleaning and oil-water separation behavior for both industrial and household importance.     

Using atmospheric pressure plasma for enhancing the deposition of printing paste on cotton fabric for digital ink-jet printing

Atmospheric pressure plasma (APP) treatment was applied as a pretreatment process to enhance the deposition of printing paste in order to improve the final colour properties of digital ink-jet printed cotton fabrics. Three printing pastes containing natural polymers, i.e. (1) sodium alginate, (2) chitosan and (3) sodium alginate-chitosan mixture, were prepared separately. After APP treatment, cotton fabric was padded with different printing pastes prior to digital ink-jet printing. Experimental results showed that APP pretreatment could increase the colour yield of the digital ink-jet printed cotton fabric significantly even after washing. In addition, other properties such as colour fastness to crocking, colour fastness to laundering, outline sharpness and anti-bacterial properties were also improved when compared with those of the control cotton fabric printed without APP pretreatment. However, the influence of printing paste on the colour properties of the digital ink-jet printed cotton fabrics depended very much on the composition of the printing paste. The scanning electron microscope images evidenced that the APP treatment could enhance the deposition of printing paste on the cotton fabric surface as proved qualitatively by both the contact angle and wetting time measurement as well as quantitatively by both the X-ray photoelectron spectroscopy and carboxyl group/nitrogen content analysis.     

阻燃超疏水棉纤维的制备及性能

将氢氧化镁(Mg(OH)₂)凝胶沉积到棉纤维上,以提高棉纤维表面粗糙度和阻燃性能,随后将含有Mg(OH)₂的棉纤维浸渍到聚二甲基硅氧烷(PDMS)溶液,获得阻燃超疏水棉织物。 并对棉纤维进行了傅里叶变换红外光谱仪(FTIR)、扫描电子显微镜(SEM)、疏水性、热稳定性、阻燃性能和耐久性测试。 结果表明,Mg(OH)₂负载到织物上,使得织物表面具有一定的微/纳米结构,形成了粗糙涂层。 当Mg(OH)₂浓度为1.0 mol/L时,Mg(OH)₂/PDMS改性的织物接触角(CA)可达158°,极限氧指数(LOI)提升至24.5%,导热系数为0.0525 W/(m·K), 具有超疏水和阻燃性能。 整理后织物经过20次洗涤,100次磨擦,极端条件处理后,CA仍大于150°,LOI值高于23%,显示了较好的耐久性。     

表面化学接枝改性阻燃棉织物的制备与性能

采用高碘酸钠对棉织物表面进行选择性氧化生成醛基,选取乙二胺与醛基反应,通过膦氢化加成反应将阻燃剂亚磷酸二甲酯接枝到棉织物表面,最后通过三羟甲基三聚氰胺对棉织物表面进行接枝改性,制备了含三羟甲基三聚氰胺/乙二胺/亚磷酸二甲酯阻燃棉织物.通过傅里叶红外光谱（FTIR）对改性后棉织物的结构进行了表征,通过极限氧指数（LOI）测试研究了其阻燃性能,通过锥形量热测试研究了其燃烧行为,通过在40℃皂水中洗涤10次考察了其耐水性能,通过扫描电子显微镜测试了其表面及燃烧后炭层的形貌.研究结果表明,经表面改性后,棉织物的LOI值由（19.5±1.0）%提高到了（43.1±1.0）%,经耐水洗测试后,LOI值仅下降至（42.6±1.0）%,保持了非常好的阻燃性能,表明通过表面接枝方法制备的三羟甲基三聚氰胺/乙二胺/亚磷酸二甲酯阻燃棉织物具有非常好的耐水洗性能.表面阻燃改性提高了棉织物在燃烧过程中的成炭性能,形成的连续膨胀的炭层较好地保护了内部织物,抑制了织物的降解和燃烧,从而提高了棉织物的阻燃性能.     

Multifunctional superhydrophobic/oleophobic and flame-retardant cellulose fibres with improved ice-releasing properties and passive antibacterial activity prepared via the sol–gel method

In this research, a two-component sol–gel inorganic–organic hybrid coating was prepared on a cotton fibre surface. An equimolar sol mixture of the precursors 1H,1H,2H,2H-perfluorooctyltriethoxysilane (SiF) and P,P-diphenyl-N-(3-(trimethoxysilyl)propyl) phosphinic amide (SiP) was applied to cotton fabric samples using the pad-dry-cure method. The surfaces of the untreated and coated cotton fibres were characterised using scanning electron microscopy, Fourier transform-infrared spectroscopy, X-ray photoelectron spectroscopy, and time-of-flight-secondary ion mass spectrometry. The functional properties of the coated cotton fabric samples were investigated using static contact angle measurements with water and n-hexadecane, the ice-releasing test, antibacterial testing against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli, thermogravimetric analysis in an air atmosphere, and vertical flammability tests. The results reveal the formation of a nanocomposite two-component inorganic–organic hybrid polymer network that is homogenously distributed over the cotton fibre surface. The presence of the SiP component in the two-component inorganic–organic hybrid coating did not hinder the functional properties imparted by the presence of the SiF component and vice versa, illustrating their compatibility. The cooperative action of the SiF and SiP components in the two-component coating provided the cotton fabric with exceptional multifunctionality, including simultaneous superhydrophobicity and high oleophobicity, passive antibacterial activity, and improved thermo-oxidative stability.     

Preparation of durable superhydrophobic surface by sol–gel method with water glass and citric acid

Durable superhydrophobic surface on cotton fabrics has been successfully prepared by sol–gel method. Cellulose fabric was first coated with silica sol prepared with water glass and citric acid as the acidic catalyst. The silica coated fabric was then padded with hydrolyzed hexadecyltrimethoxysilane afterwards obtaining low surface energy. Water contact angle and hydrostatic pressure were used to characterize superhydrophobicity and washing durability. Scanning electron microscopy was used to characterize the surface morphology changes after certain washing times. All results showed good durable hydrophobicity on cellulose fabrics. In addition, the influence of citric acid and sodium hypophosphite (NaH₂PO₂) on the durability of hydrophobicity was also investigated. The durability of treated cotton improved with the increase of concentration of citric acid in the presence of NaH₂PO₂. It could be concluded that citric acid acted as multi-functional heterogeneous grafting chemicals to improve washing durability of hydrophobicity by forming the ester bonds between cotton fabric and silica sol and improved the durability of hydrophobicity.     

Synthesis and structure-activity relationship exploration of carbon-supported PtRuNi nanocomposite as a CO-tolerant electrocatalyst for proton exchange membrane fuel cells

A carbon-supported PtRuNi nanocomposite is synthesized via a microwave-irradiated polyol plus annealing synthesis strategy. The catalyst is characterized by transmission electron microscopy, powder X-ray diffraction, energy dispersive spectroscopy, and X-ray photoelectron spectroscopy. The data are discussed with respect to those for the carbon-supported PtRu nanocomposite prepared following the same way. The characterizations show that the inclusion of Ni in the PtRu system has only a small effect on the particle size, the structure, and the compositional homogeneity. CO-stripping voltammetry and measurements on the single proton exchange membrane fuel cells show that the PtRuNi/C catalyst has an improved activity for CO(ads) electro-oxidation. An accelerated durability test on the catalyst exhibits insignificant loss of activity in acidic media. On the basis of the exploration of the structure-activity relationship, a mechanism for the improved performance of the catalyst is proposed. It is suggested that the improved CO-tolerant performance of the PtRuNi/C nanocomposite should be related to the hydrogen spillover on the catalyst surface, the enhanced oxidation of CO(ads) by nickel hydroxides, and the high proton and electronic conductivity of the hydroxides. The nickel hydroxide passivated surface and/or anchoring of metallic nickel in the platinum lattice may contribute to the durability of the catalyst in acid solution.     

Antimicrobial Performance of Plasma Corona Modified Cotton Treated with Silver Nitrate

Cotton fabric was treated by corona plasma discharge at different powers and numbers of passages. The carboxyl group content was determined by Methylene Blue staining and titration. Then, the untreated and treated cotton fabrics were treated with silver nitrate, and laundering test was carried out. The inductively coupled plasma optical emission spectroscopy (ICP-OES) analysis for silver and antibacterial tests were done. The surface bonding and morphology were studied by FTIR/ATR spectroscopy and scanning electron microscopy (SEM), respectively. The plasma corona discharge treatment of cotton fabric increases the content of carboxyl groups. An increase in the power of plasma treatment increases the content of carboxyl groups and adsorption of silver ions. As a result, the antibacterial effect is enhanced and becomes more stable after repeated laundering.     

Surface chemical analysis of raw cotton fibres and associated materials

The surface chemical composition of raw unscoured cotton was successfully investigated by the surface analytical techniques X-ray Photoelectron Spectroscopy (XPS) and Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS). The presence of non-cellulosic material at the fibre surface was established and determined to be a complex mixture of fatty acids, alcohols, alkanes, esters and glycerides. The effect of scouring and bleaching was to reduce the surface concentration of these materials but even after aqueous processing some non-cellulosic material residue was still detected at the fibre surface.     

Surface and bulk cotton fibre modifications: plasma and cationization. Influence on dyeing with reactive dye

The surface of cotton fabrics was functionalized through corona plasma treatments and/or by cationising the whole of the fibre with an epihalohydrin. The effects of both treatments, individually and in combination are analyzed through wettability studies, by X-ray photoelectron spectroscopy (XPS), Scanning electron microscopy (SEM), and also by dyeing studies with an hetero bis functional reactive dye. Plasma improved wetting properties, exhaustion of the dyebaths and K/S_corr of the fabrics through surface functionalisation. Cationising of the cotton highly increased the exhaustion of the dyebaths and produced a dramatic improvement in K/S_corr. Plasma treatment previous to cationising increased the impregnation of the fabrics, but the effects of both treatments on dyeing parameters are additive only in column water rise and generally the effects obtained by cationising with the epihalohydrin prevail. The differences between both treatments are discussed in terms of surface functionalisation of the cotton fibres.