UV-grafting coloration of cotton and wool fabrics using bismethacrylated quinizarin dye

A novel bifunctional quinizarin dye possessing two photoactive methacrylate groups was synthesized by the reaction of quinizarin with methacryloyl chloride. The synthesized dye, a low substantive dye under the conventional dyeing process, can be photografted onto cotton and wool fabrics at room temperature without neutral salts, which makes it a novel coloration process of excellent environmental friendliness. The concurrent polymerization and grafting of the synthesized dye onto cotton or wool can be assisted by a photoinitiator and acrylic acid in the case of cotton grafting. Moreover, color yields of the grafted fabrics improved significantly with the photografting of the bifunctional dye. The bifunctional dye can be photopolymerized with the increase in UV energy to 25 J/cm² and the oligomeric dye has a degree of polymerization of 5 or more. Furthermore, the color fastness properties of the grafted fabrics were superior to those of the dyed fabrics via exhaustion.     

Flame retardant properties of triazine phosphonates derivative with cotton fabric

The flame retardant behavior of cotton fabric treated with phosphorus-nitrogen containing triazine compound was evaluated. It was found that cyanuric chloride (2,4,6-trichloro-1,3,5-triazine) is an excellent starting material for the preparation of phosphonate flame retardants that interact well with cotton to improve flame resistance (FR) performance. Tetraethyl 6-chloro-1,3,5-triazine-2,4-diyldiphosphonate (TECTDP) has been prepared by a simple one-step reaction in high yield (98.0 %). Cotton fabrics treated with TECTDP result in covalent bond formation between TECTDP and hydroxyl groups in cotton fabrics. This FR system provides an efficient flame retardant for cotton textiles at low cost to meet government mandates. In this study, the FR material was synthesized and characterized by ¹H and ¹³C nuclear magnetic resonance (NMR), and LC-MS spectroscopy. The chemical structure of cotton twill fabric treated with TECTDP by pad-dry-cure method was analyzed by FT-MIR and SEM. Furthermore, the thermal and flammability properties were evaluated by thermogravimetric analysis (TGA), limiting oxygen index (LOI, ASTM D-2863-09), and a vertical flame test (ASTM D-6413-08).     

Multifunctional,Hydrophobic and Flame-retarded Cotton Fabrics Modified with Liner Piperzine/Phosphorous/Polysiloxane Copolymer

α,ω-di[(4-butoxy-piperazin-1-yl)-phosphinic acid methyl ether]-terminated linear polysiloxane (PNPDMS) was synthesized and utilized as the flame retardant and hydrophobing agent. The flame retardance and thermal decomposition behaviors of cotton fabrics were systematically estimated by limiting oxygen index (LOI), thermogravimetric analysis and vertical burning test, respectively. It was found that the LOI of cotton fabric treated with PNPDMS enhanced to 29.82 % compared with cotton fabric without treatment, whose LOI was only 18.00 %. The treated cotton fabric showed a shorter char length, a shorter After-flame time, and no After-glow time as revealed in vertical burning test. The mechanical property in treated cotton fabric was slightly decrease. Furthermore, the grade of water repellency of treated cotton fabric reached to 90 and water contact angle (WCA) increased to 141.90° compared with cotton fabric without treatment whose WCA was 62.80°. The result showed that the cotton fabric treated with PNPDMS exhibited excellent flame retardance and hydrophobic properties.     

Nano-TiO<Subscript>2</Subscript> based multilayer film deposition on cotton fabrics for UV-protection

Nano-TiO₂ based multilayer nanocomposite films were fabricated on cationically modified woven cotton fabrics by layer-by-layer molecular self-assembly technique. Cationization process was used to obtain cationic surface charge on cotton fabrics. Attenuated total reflectance Fourier transform infrared spectroscopy analyses were used to verify the presence of cationic surface charge and multilayer films deposited on the fabrics. Scanning electron microscope micrographs of poly(sodium 4-styrene sulfonate)/TiO₂, nano polyurethane/TiO₂, and TiO₂/poly(diallyldimethylammonium chloride) multilayer films deposited on cotton fabrics were taken. With nano-TiO₂ based multilayer film deposition, the protection of cotton fabrics against UV radiation is enhanced. The UV protection durability of the self-assembled multilayer films deposited on the cotton fabrics was analyzed after 10 and 20 washing cycles at 40 °C for 30 min. Air permeability and whiteness value analysis were performed on the untreated and multilayer film deposited cotton fabrics. The effect of layer-by-layer deposition process on tensile strength properties of the warp and weft yarns was determined.     

Surfactant effects on application of a hydrophobic, fluoropolymer coating to cotton by admicellar polymerization

Various methods have been used previously to impart hydrophobicity to cotton. In this study, thin co-polymer films of trifluoroethyl acrylate (TFEA) and octafluoro pentyl methacrylate (OFPM) were formed on cotton using individual fluorosurfactants and surfactant mixtures through the process of admicellar polymerization. Efficacy of 6 different fluorosurfactant systems and process conditions including surfactant type, concentration, adsorption/adsolubilization time, polymerization time, and monomer concentration have been investigated in order to obtain hydrophobic coatings on woven cotton fabric. Adsolubilization times as short as 2 h and polymerization times as short as 1 h yielded satisfactory performance. Characterization of the hydrophobic polymer films obtained included static contact angles, SEM imaging, elemental analysis and XPS analysis. Treated fabrics exhibited good water repellency for several surfactants and surfactant mixtures with initial supernatant monomer concentrations of 4 mM. Surfactant mixtures were able to outperform the separate individual species in admicellar polymerization.     

Highly flame retardancy of cotton fabrics with a novel phosphorus/nitrogen/silicon flame-retardant treating system

A novel reactive flame retardant (FR) containing phosphorus, nitrogen, and silicon was synthesized successfully, and its chemical structure was fully characterized by Fourier transform infrared spectrometry and nuclear magnetic resonance spectrometry (¹H-NMR and ³¹P-NMR). Then it was used to impart flame resistance to cotton fabrics. Vertical flammability and limiting oxygen index test were used to evaluate the flame retardancy of the cotton fabrics treated with FR. When the cotton treated with 150 g/l FR and 50 g/l sodium hypophosphite, the finished cotton can pass the vertical flammability test. Thermogravimetry (TG) was used to evaluate thermal behavior of FR and cotton fabrics. TG results demonstrated that the FR has good thermostability and char-forming ability. After treatment with FR, the thermal stability of the cotton fabrics was clearly improved, indicating that the FR can protect cotton fabric from fire to a certain degree. Furthermore, attenuated total reflection Fourier transform infrared spectroscopy was utilized to characterize the chemical structure of FR treated cotton fabrics. Finally, the surface morphology in different regions of the treated cotton was observed using scanning electron microscopy.     

Synthesis of core-shell fluorinated acrylate copolymers and its application as finishing agent for textile

Core-shell fluorinated acrylate copolymers emulsion was thus synthesized via the core-shell emulsion polymerization with the fluorinated monomers and acrylic monomers as the main raw materials and its properties were studied. PFMA, the fluorinated acrylate monomers, was synthesized by the esterification of perfluorooctanoyl chloride (PFOC) and hydroxypropyl methacrylate (HPMA). Then the core-shell fluorinated acrylate copolymers emulsion with a poly(MMA/BA/St) core and a poly(PFMA/MMA/BA) shell was synthesized via a starved semi-continuous core-shell emulsion polymerization method by using KPS and sodium bicarbonate as the initiator/buffer system and SDS/Twain 80 as the commixture emulsifier. Lastly, the synthesized copolymers was applied as textile finishing agent for cotton textile. The results of FT-IR and NMR indicated that PFMA had been synthesized as expected and effectively combined in the emulsion copolymerization. The GPC, zeta potential, TEM and DSC showed that the particles had uniform spherical core-shell structure with a diameter of 65-150 nm, and the distribution and emulsion stability was satisfactory. As XPS, FESEM and AFM shown, a hydrophobic structure which was similar to the structure of the lotus leaf were formed and the surface hydrophobicity of the films can be improved. Based on the analysis of DSC, thermal stabilities of the films were enhanced with the increase of fluorine content. Besides, FESEM of textiles showed that the surface of treated textiles were smooth and the edges were clear and visible, indicating significant improvement of the performance on water and oil repellent.     

Facile fabrication of superhydrophobic cotton fabric from stearyl methacrylate modified polysiloxane/silica nanocomposite

The stearyl methacrylate modified polysiloxane/nanocomposite was synthesized by graft copolymerization between stearyl methacrylate modified polysiloxane with pendent epoxy groups and amino-functionalized nano silica. Then it was utilized to fabricate the superhydrophobic cotton fabric by one-step method. The structures, chemical compositions, thermal properties, surface morphology and wettability were characterized by Fourier Transform Infrared Spectrum (FT-IR), X-ray photoelectron spectroscopy (XPS), Thermo-gravimetric analyzer (TGA), Scanning electron microscopy (SEM) and Static contact angle analyzer. Results showed that a hydrophobic polysiloxane film and many nano-scaled tubercles were coated on the surface of the treated cotton fabrics plus their inherent microscaled roughness, which were the reasons why cotton fabric changed from hydrophilicity to hydrophobicity. In addition, with increase of the amount of nanocomposite, hydrophobicity of the treated cotton fabric would be enhanced; water contact angle of this fabric could attain 157°, which was higher than 141.5° reached by the fabric treated with stearyl methacrylate modified polysiloxane. The superhydrophobic cotton fabric also possessed favorable washing durability. On the other hand, its air permeability, color and softness would not be influenced instead.     

Highly Durable and Robust Superhydrophobic/Superoleophilic Cotton Fabric with Well-designed Roughness for Oil/Water Separation

Herein we report a simple and reproducible method for fabricating highly durable and robust superhydrophobic and superoleophilic cotton fabrics via simultaneous radiation-induced graft polymerization of glycidyl methacrylate and subsequent chemical modifications with aminopropyltriethoxysilane and hexamethyldisilazane. The chemical structure and the surface topography of the pristine and the modified cotton fabrics were investigated in detail by ATR-FTIR, XPS, and ²⁹Si NMR, and a grafting layer was successfully immobilized onto the surface of the cotton fabric by forming covalent bonds. Multi-dimensional surface roughness was created by combining micro-sized fibers of the cotton fabric, nanoscaled protuberances of the grafting chain, and molecular level spherical projection points of silicon methyl. The superhydrophobic cotton fabric exhibited long-term stability, ultra-high durability and robustness, and maintained its properties even after 25 wash cycles. The fabric also showed excellent water repellency with a water contact angle of 153 ° and a high efficiency of oil/water separation (98 %). The superhydrophobic/superoleophilic cotton fabric developed in the present work exhibits important potential applications in superhydrophobic textiles and oil/water separation.     

Synthesis and Application of Polyurethane-Modified Silicone as Finishing Agent for Cotton Fabric

The polyurethane modified organic silicone (PU-SA) was successfully synthesized via step-by-step polymerization with isophorone diisocyanate (IPDI) and polypropylene glycol (PPG) used as monomers, dibutyltindilaurate (DBTDL) as the catalyst, trimethylolpropane (TMP) and N-methyldiethanolamine (MDEA) as the chain extender, and amino-terminated siloxane (SA) as the blocking agent. The chemical structure of PU-SA was characterized by Fourier transform infrared spectroscopy (FT-IR). X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM) showed that PUSA had been successfully finished on the surface. Additionally, the thermogravimetric analysis (TGA) demonstrated that the PU-SA treated fabrics showed low decomposition temperature and slightly high char residue. As a finishing agent, the effect of PU-SA on the handle of cotton fabrics was also studied by using a Kawabata Evaluation System for Fabrics (KES-F). The experimental results found that PU-SA had a significant improvement on the bending properties, surface properties, and compressional properties. Moreover, the mechanical and anti-wrinkle properties of the cotton fabrics were also enhanced.     

Synthesis of HBP-HTC and its application to cotton fabric as an antimicrobial auxiliary

A quaternary ammonium compound, 2-hydroxypropyltrimethylammonium chloride amino-terminated hyper-branched polymer (HBP-HTC), was synthesized from an amino-terminated hyperbranched polymer (HBP-NH₂) and 2,3-epoxypropyltrimethylammonium chloride (EPTAC) as a grafting agent in aqueous solution. Its molecular weight and possible structure were characterized by gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (¹H-NMR). The cotton fabric was treated with 2 g/l HBP-HTC aqueous solution for 30 min at room temperature to provide the cotton fabric with antimicrobial properties. The antimicrobial activities of the HBP-HTC aqueous solutions and the HBP-HTC treated cotton fabrics were evaluated quantitatively. The results indicated that the HBP-HTC treated cotton fabric showed 99.92 % reduction of bacteria S. aureus and 99.66 % reduction of bacteria E. coli, respectively. The antimicrobial activities of the HBP-HTC treated cotton fabrics were maintained at over 99.00 % reduction level even after being exposed to 20 consecutive home laundering conditions.     

Formaldehyde free cross-linking agents based on maleic anhydride copolymers

Low molecular weight copolymers of maleic anhydride and vinyl acetate were prepared to develop formaldehyde free cross-linking agents. Since lower molecular weight is favorable for efficient penetration of the finishing agent into the cotton fibers in the padding process, the concentration of the initiator, chain transfer agent and the monomer ratios were varied to obtain copolymers of low molecular weights. The prepared polymers were characterized by GPC,¹H-NMR, FTIR, DSC and TGA. Copolymers of molecular weights of 2 000 to 10 000 were obtained and it was found that the most efficient method of controlling the molecular weight was by varying the monomer ratios. Poly(maleic anhydride-co-vinyl acetate) did not dissolve in water, but the maleic anhydride residue hydrolyzed within a few minutes to form poly(maleic acid-co-vinyl acetate) and dissolved in water. However, the maleic acid units undergo dehydration to form anhydride groups on heating above 160 °C to some extent even in the absence of catalysts. The possibility of using the copolymers as durable press finishing agent for cotton fabric was investigated. Lower molecular weight poly(maleic anhydride-co-vinyl acetate) copolymers were more efficient in introducing crease resistance, which appears to be due to the more efficient penetration of the crosslinking agent into cotton fabrics. The wrinkle recovery angles of cotton fabrics treated with poly(maleic anhydride-co-vinyl acetate) copolymers were slightly lower than those treated with DMDHEU and were higher when higher curing temperatures or higher concentrations of copolymer were used, and when catalyst, NaH₂PO₂, was added. The strength retention of the poly(maleic anhydride-co-vinyl acetate) treated cotton fabrics was excellent.     

Eco-friendly and Durable Antibacterial Cotton Fabrics Prepared with Polysulfopropylbetaine

A novel antibacterial agent polysulfopropylbetaine (PSPB) bearing carboxyl groups was synthesized and its application on cotton fabric to provide durable antibacterial property was also presented. The successful synthesis of PSPB and its immobilization onto the cotton fabric surface were verified by a series of tests including FTIR, ¹H NMR, XPS and SEM. Viable cell counting method was employed to investigate antibacterial properties of the finished cotton fabrics. It was found that the cotton fabrics treated with PSPB were endowed with desirable antibacterial activity against both gram-negative bacteria Esherichia coli (E.coli, AATCC 6538) and gram-positive bacteria Staphylococcus aureus (S.aureus, AATCC 25922), with the bacterisotatic rates of 99.69 % and 99.95 %, respectively. Notably, the bacterial reduction rates still maintained over 90 % against both bacteria even after 50 consecutive laundering cycles. Moreover, tests concerning the hydrophilicity, air permeability, water vapor transmission, mechanical properties as well as thermal properties were carried out systematically. The experimental results indicated the hydrophilic performance, air permeability and moisture penetrability of the cotton fabrics finished with PSPB were improved greatly in spite of a slight reduction in thermal performance and little obvious influence on mechanical performance. The antibacterial cotton fabric has the potential to be applied in sportswear, underwear, household textiles, medical fields and much more.     

Evaluation of bamboo charcoal/stainless steel/TPU composite woven fabrics

Composite woven fabric satisfies what people require. Bamboo charcoal (BC) has been identified as a multifunctional material that has far-infrared ray, anions, deodorization and etc. BC fibers and yarns were made of bamboo charcoal powders and have further become a pervasive materials used in textile industry. In this study, cotton yarns, stainless steel/cotton (SS/C) complex yarn, bamboo charcoal/cotton (BC/C) complex yarns were woven into the plain, twill and Dobby composite woven fabrics. The warp yarn was composed of cotton yarns, and the weft yarn was made up of BC/C and SS/C complex yarns with a picking ratio of 1:1 and 3:1. Thermoplastic polyurethanes (TPU) film was then attached to the composite woven fabrics, forming the BC/SS/TPU composite woven fabrics. Tests of electromagnetic shielding effectiveness (EMSE), far-infrared emissivity, anions, water resistance, and water vapor permeability measured the single-layer, two-layer and four-layer composite woven fabrics, obtaining a far-infrared emissivity of 0.95 by 39.8 counts per minute, an anion count of 149 amount/cc, an EMSE of −11.87 dB under frequency of 900 MHz, a surface resistivity of 8×10⁻⁶ Ω/square, a water resistance of −8219 mmH₂O, and water vapor permeability of 989 g/m²·h and 319 g/m²·24 h in accordance with JIS L 1099 A1 and ASTM E96 BW.     

Flexural stiffness of core spun cotton/spandex weft knitted structures under relaxation and machine washing treatments

In this research work, behavior of flexural stiffness of core spun cotton spandex single jersey, 1x1 rib and interlock fabrics was studied under relaxation and machine washing treatments. Results are compared with similar fabrics made from 100 % cotton. Fabric weight density increased with the progression of treatments and it is proportionate to the fabric tightness factor (stitch length^?1). Even though both types of fabrics had same machine set stitch lengths, cotton/spandex fabrics have shown the higher fabric weight densities than that of 100 % cotton fabrics. Although 1x1 rib and single jersey fabrics knitted with the same machine set stitch lengths, rib fabrics have given higher fabric weight densities than single jersey fabrics. Among the three knitted structures, interlock fabrics with higher machine set stitch lengths gave the higher fabric weights. Fabric stiffness and flexural rigidity have given higher values under the progression of treatments and it was found that higher values of stiffness have given by cotton/spandex knitted fabrics compared to their cotton fabrics. Fabric stiffness and flexural rigidity in wale direction were higher than that in course direction, but it is only observed in single jersey fabrics. However, 1x1 rib and interlock fabrics have shown an opposite behavior. It was also observed a positive correlation between TF (i.e.: stitch length^?1) and bending length/flexural rigidity in both fabric types. Lower flexural rigidities reported with single jersey structures and highest values gave with interlock structures of cotton/spandex and cotton fabrics.     

Effect of nano SrTiO3 supporting nano TiO2 on self-cleaning of cotton fabric

This study reports the results of an investigation aiming at finding what affect nano titania (TiO₂) and nano strontium titanate (SrTiO₃) on self-cleaning of cotton fabrics. The photocatalytic activity of nano strontium titanate has been examined on cotton fabric under UV irradiation in various concentrations in mixing of nano titania. The amount of loaded nano titania and nano strontium titanate particles on cotton fabrics were investigated using X-ray fluorescence spectrometry (XRF) and crystallinity of coatings by X-ray diffraction spectroscopy (XRD). The treated cotton fabrics, which were stained with two common synthesized dyes, were exposed to 400 W UV radiation for 30 hours and their self-cleaning property was investigated by a reflectance spectrophotometer. Scanning electron microscope (SEM) images show pervasion of nano materials on the surface of the treated cotton. Adding nano strontium titanate to nano titania showed the most promising photocatalytic activity toward dye degradation.     

Superhydrophobicity,Self-cleaning and Flame Retardancy Properties of Cotton Fabric

A simple and facile method for fabricating the cotton fabric with superhydrophobicity, self-cleaning and flame retardancy was described in the present work. Three types of antimony pentoxide sol (Sb₂O₅), aluminum hydroxide sol (Al(OH)₃) and 1H,1H,2H,2H-perfluorodecyltriethoxysilane (fluoroalkyl silanes) were used as coating for the cotton fabric. It was found that Sb₂O₅ and Al(OH)₃ exhibited significant synergistic effects on the flame retardancy. When the weight ratio of Sb₂O₅/Al(OH)₃(content 30 wt%) was 1:3, the results showed that the limiting oxygen index (LOI) value was 45.1 %, smoke density (SDR) value was 35 %, and it still passed UL94 V-0 rating. The cotton fabrics coated with fluoroalkyl silanes/Sb₂O₅/ Al(OH)₃ showed a superhydrophobicity, anti-contamination and self-cleaning properties. In addition, the results exhibited the outstanding superhydrophobicity, oil/water separation, excellent waterproofing durability and flame retardancy of cotton fabric after 1000 cycles of washing by water, the LOI value was 40.1 %, SDR value was 39 % and WCA was 152° after 1000 cycles of washing. We believe that this simple, environmentally friendly and versatile fabrication of the cotton fabric had excellent real-life applications.     

Properties of anti-UV-finished cotton fabrics cured by blue light irradiation

To decrease the pollution discharge and energy consumption resulting from textile finishing using the conventional pad-dry-cure process, a blue light-curable digital finishing for textile was innovatively proposed. Based on the mechanism of blue light curing technique, a combination of the blue light curing process and anti-UV finishing was established in this study. A blue light-curable anti-UV finishing solution containing oligomers, monomers, photoinitiators, and anti-UV agents was padded onto the surface of the cotton fabrics, and then cured to form a tough film under blue light irradiation. The ultraviolet protection factor (UPF) value of the finished cotton fabrics was 50, the top level of international standards, demonstrating excellent UV resistance. The finished cotton fabrics also showed good rubbing and washing durability, and acceptable handle. The integration of an anti-UV finishing with the blue light curing technique presents some unique advantages in terms of environmental protection and application potential.     

Hydrophilic modification of PET fabric via continuous photografting of acrylic acid (AA) and hydroxyethyl methacrylate (HEMA)

Poly(acrylic acid) and poly(hydroxyethyl methacrylate) were introduced onto PET fabrics by UV-induced photografting to improve its hydrophilicity. Several factors affecting the photografting were studied including irradiation energy, monomer, and photoinitiator (PI) concentrations. ATR and ESCA analyses proved successful grafting of the two monomers onto PET. Morphology of fabric surface was examined using FE-SEM. Both zeta potential and water wetting time of the grafted PET fabrics decreased with increasing grafting yield. Also cationic dyeability of the grafted PET fabrics increased because of the increased electrostatic interactions between the anionic dyeing sites and cationic dyes.     

Chemical Bonding of Organic Dye onto Cotton Fibers Using Silane as Coupling Agent (I)

A derivative of an optical brightening agent (organic dye), i.e., 2,6-dibromo-4-flouroaniline (synthesized and reported previously) has been chemically bonded to cotton fabrics through a coupling agent, i.e., 3-(2-aminoethylamino)- propyltrimethoxy silane. These chemically treated cotton fabrics have been characterized by FTIR spectroscopy, color observation, tear properties determination, and UV-DRS analysis. The relevant spectra of FTIR confirm chemical bonding of the silane with cotton on one end and with the dye on the other. Comparison of the various treated and untreated cotton samples before and after washing by visual observations confirms the claim of chemical bonding of the dye with the cotton. The consistent decreasing patterns observed in tear strengths of the treated cloths with increase in concentration of the respective chemical validate modification of the cotton cloths. UV-DRS analysis of the modified cotton cloths show that the reflectance decreases with the use of silane.