Preparation, characterization, and antimicrobial property of cotton cellulose fabric grafted with poly (propylene imine) dendrimer

Two generations of poly (propylene imine) dendrimer with amino terminated groups (G2- and G5-PPI-NH₂) were grafted on cotton cellulose fabric using cross linking agents (citric or glutaric acids). Fourier transform infrared (FTIR) spectroscopy identified ester groups which were formed between hydroxyl groups of the cotton fabric and carboxylic groups of the cross linking agents. Also, attenuated total reflectance-FTIR (ATR-FTIR) analysis confirmed formation of amide groups between the carboxylic groups of the cross linking agents and the amino end groups of the dendrimers. Nitrogen content (N-content) analysis revealed the presence of the dendrimers on the cotton fabric even after 5 washing cycles. In order to study the dispersion of the PPI dendrimers on the surface of the cotton fabric, field emission scanning electron microscopy (FE-SEM) was performed. The particle size distribution of the G2- and G5-PPI-NH₂ aqueous solutions was also determined by dynamic light scattering (DLS) analysis. Antimicrobial activity of the PPI dendrimer aqueous solutions and the cotton cellulose fabric grafted with the dendrimers was evaluated both quantitatively and qualitatively against Gram-positive bacterium (Staphylococcus aureus), Gram-negative bacteria (Pseudomonas aeruginosa and Escherichia coli) and fungus (Candida albicans). The dendrimer grafted cotton cellulose fabric exhibited a 99 % reduction in bacterial counts against S. aureus, E. coli and C. albicans. The antimicrobial activities of the grafted cotton cellulose fabric with the PPI dendrimers were maintained even after 5 washing cycles.     

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.     

Novel multifunctional water- and oil-repellent,antibacterial, and flame-retardant cellulose fibres created by the sol–gel process

This research aimed to prepare cotton fibres with novel multifunctional water- and oil-repellent, antibacterial, and flame-retardant properties. A three-component equimolar sol mixture, which included 1H,1H,2H,2H-perfluorooctyltriethoxysilane, 3-(trimethoxysilyl)-propyldimethyloctadecyl ammonium chloride, and P,P-diphenyl-N-(3-(trimethoxysilyl)propyl) phosphinic amide, was applied to the cotton fabric using the sol–gel process. The presence of the coating on the cotton fibres was confirmed by Fourier transform-infrared spectroscopy and X-ray photoelectron spectroscopy. The functional properties of the coated cotton fabric were determined from liquid contact angle measurements and antibacterial activity, burning behaviour, and thermo-oxidative stability studies. The results demonstrate that a unique, compatible, and uniform organic-inorganic hybrid polymer network was formed on the fabric surface, which preserved its simultaneous hydrophobic (water contact angle of 135 ± 2°), oleophobic (n-hexadecane contact angle of 117 ± 1°), and bactericidal (bacterial reduction of 100 %) properties and incorporated the enhanced thermo-oxidative stability of the modified cellulose fibres.     

The antimicrobial activity of the cotton fabric grafted with an amino-terminated hyperbranched polymer

An amino-terminated hyperbranched polymer (HBP-NH₂) was grafted to cotton fabric by a reaction between the aldehyde groups of oxidized cotton fabric and the amino groups of the HBP-NH₂ to provide cotton fabric with durable antimicrobial properties. The antimicrobial activities of the HBP-NH₂ aqueous solutions and the HBP-NH₂ grafted cotton fabrics were evaluated quantitatively against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). The results indicated that the HBP-NH₂ grafted cotton fabric showed 92% of bacterial reduction to S. aureus and 95% of bacterial reduction to E. coli, respectively. The antimicrobial activities of the HBP-NH₂ grafted cotton fabrics were maintained at over 91% reduction level even after being exposed to 20 consecutive home laundering conditions. Several influence factors, which may affect the amount of HBP-NH₂ grafted onto the cotton fabrics, were also discussed.     

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.     

自支撑柔性氮掺杂碳织物电极的制备与性能研究

本文以纯棉织物为基底,吡咯单体为氮源,采用简单的原位聚合-高温煅烧的方法制备了自支撑柔性氮掺杂织物（N-CT）. 利用傅立叶红外技术、X射线光电子能谱、比表面积测试、扫描电子显微镜对所得产物进行结构与形貌表征. 结果表明,碳化后聚吡咯主要以纳米碳球包覆在碳织物表面,N-CT电极的比表面积为495.0 m²·g^-1,其含氮量为2.26%. 电化学测试表明,在0.5 A·g^-1的电流密度下N-CT电极的比电容器为256.2 F·g^-1,经过5000次的恒流充放电循环后电容保持率为98.3%,库伦效率保持率在98.8%左右,具有良好的柔性和机械性能.     

Cotton fabric modification for imparting high water and oil repellency using perfluoroalkyl phosphate acrylate via γ-ray-induced grafting

The perfluoroalkyl phosphate acrylates were grafted onto a cotton fabric via γ-ray irradiation to improve the hydrophobic and oleophobic properties. The change in chemical structure of grafted cotton fabric was detected by the Fourier transform infrared spectroscopy and the X-ray photoelectron spectroscopy. The contact angles for water and sunflower oil were determined to be over 150° and 140°, respectively, after irradiated with a dose range of 471–5664 Gy. The flame retardancy of the fabric with a grafting ratio of over 13.0 wt% was improved, reaching to 24 compared with 18 of which before grafted, according to the limiting oxygen index measurement. The microstructure of the fabric before and after grafted was observed by the scanning electron microscope.     

Kapok/cotton fabric–polypropylene composites

Kapok/cotton fabric has been used as reinforcement for conventional polypropylene and maleic anhydride grafted polypropylene resins. Treating the reinforcement with acetic anhydride and sodium hydroxide has modified the fabric (fibres). Thermal and mechanical properties of the composites were investigated. Results show that fibre modification gives a significant improvement to the thermal properties of the plant fibres, whereas tests on the mechanical properties of the composites showed poor tensile strength. Mercerisation and weathering were found to impart toughness to the materials, with acetylation showing slightly less rigidity compared to other treatments on either the fibre or composites. The modified polypropylene improved the tensile modulus and had the least toughness of the kapok/cotton reinforced composites. MAiPP reinforced with the plant fibres gave better flexural strength and the same flexural modulus at lower fibre content compared with glass fibre reinforced MAiPP.     

Imparting durable antimicrobial properties to cotton fabrics using quaternary ammonium salts through 4-aminobenzenesulfonic acid-chloro-triazine adduct

A 4-aminobenzenesulfonic acid-chloro-triazine adduct was successfully synthesized in a laboratory scale and treated with cotton fabrics in order to increase the anionic sites and thereby % exhaustion of cationic compounds. Two Quaternary Ammonium Salts (QAS) was investigated namely, Cetylpyridinum chloride (CPC) and Benzyldimethylhexadecyl ammonium chloride (BDHAC) which are widely accepted as strong antimicrobial agents. The reaction mechanism involved in the synthesis of the reactive adduct as well its application to cotton fabric were demonstrated in detail. The effects of application parameters, namely pH, temperature and liquor ratio were examined. The reaction efficiency was determined through monitored % exhaustion of the adduct by cotton fabric. Antimicrobial activity of the treated cotton sample was studied against Staphylococcus aureus according to AATCC test method 100-1999. Results obtained show that the treated fabric shows higher antimicrobial activity compared with the untreated fabric. The results depict also that % exhaustion decreases as the pH, temperature and liquor ratio increase. Moreover, the appropriate predictable empirical models were developed using Excel solver function incorporating interaction effects of all variables to predict the % exhaustion and the satisfactory results (R² > 0.98) were obtained.     

Durable antimicrobial cotton fabrics containing stable quaternarized N-halamine groups

A novel N-halamine precursor with tertiary amino group (5,5-dimethylhydantoinyl-3-ylethyl)-dimethylamine (DEADH), was synthesized and then covalently bonded onto cotton fabrics modified by 3-chloropropyltrimethoxysilane to form quaternarized N-halamine precursor grafted cotton fabrics which could be transferred to N-halamine structure upon exposure to dilute sodium hypochlorite solution. The grafted cotton fabrics were characterized by FT-IR, X-ray photoelectron spectroscopy, and field emission scanning electron microscope. The antimicrobial test showed that the cotton fabrics grafted with the quaternarized N-halamine were capable of 7-log inactivation of Staphylococcus aureus and Escherichia coli O157:H7 within 1 min of contact time. Very interestingly, it was found that the grafting process and following chlorination had almost no adverse effect on the tensile strength of cotton fabrics. Furthermore, the antimicrobial cotton fabrics exhibited good washing durability and stability.     

Synthesis of a novel synergistic flame retardant based on cyclopolysiloxane and its flame retardant coating on cotton fabric

A synergistic flame retardant (silicon, phosphorus and nitrogen) based on cyclic polysiloxane, ammonium salt of tetramethylcyclosiloxyl-piperazin-phosphinic acid (APCTSi) was successfully prepared and firmly bonded to cotton fabric through a chemical grafting method. The chemical structure of APCTSi was characterized by Fourier transform infrared (FTIR) spectroscopy, ¹H and ³¹P nuclear magnetic resonance (¹H NMR and ³¹P NMR). The scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM–EDX) proved that APCTSi successfully adhered to the surface of cotton fabric and the elements on the surface of cotton fabric were evenly distributed. The flame retardant properties were characterized by limiting oxygen index (LOI), vertical burning test, thermogravimetric (TG) analysis and TG-FTIR. The limiting oxygen index (LOI) can reach 30.9% with a char length of 8.7 cm for the weight gain of APCTSi was 16.2%. The combustion behavior was characterized by cone calorimetry test. The peak heat release rate (pHRR) and total heat release (THR) values of treated cotton fabric decreased by 30% and 48% respectively compared to that of pure cotton fabric. All the results proved that the cotton fabric treated by APCTSi had the flame retardant effect of condensed phase (forming stable char layer) and gas phase (releasing nonflammable gases).

Graphic abstract

     

Maintaining hand and improving fire resistance of cotton fabric through ultrasonication rinsing of multilayer nanocoating

Thin films of environmentally benign polyelectrolytes, cationic chitosan (CH) and anionic poly(sodium phosphate) (PSP), were deposited on cotton fabric via layer-by-layer (LbL) assembly to reduce flammability. This CH–PSP nanocoating promotes charring of the cotton, rendering the fabric self-extinguishing. The coated fabric was rinsed in an ultrasonication bath between deposition steps to improve the softness (i.e., hand) of the coated fabric. Ultrasonication is believed to remove weakly adhered polyelectrolyte, preventing the fabric from becoming stiff, while improving anti-flammable behavior at a given coating weight. At 17 bilayers, only 9.1 wt% was added to the cotton, yet the coated cotton consistently passed vertical flame testing. Electron microscopy provides evidence of intumescence and confirms the cleaner deposition afforded by ultrasonication. The reduction in peak heat release rate and total heat release, as measured by micro cone calorimetry, were 73 and 81 % respectively, which is a new benchmark in LbL flame retardant coating on cotton. The mechanical properties of the fabric were measured using the Kawabata evaluation system, which showed that ultrasonication rinsing significantly improved the hand. The ability to render cotton fabric self-extinguishing, while maintaining a soft hand, marks a major milestone in the development of these environmentally-benign nanocoatings.     

Preparation and enhanced properties of poly(propylene)/ silica‐grafted‐hyperbranched polyester nanocomposites

A series of poly(propylene) silica‐grafted‐hyperbranched polyester nanocomposites by grafting the modified hyperbranched polyester (Boltorn? H20), possessing theoretically 50% end carboxylic groups and 50% end hydroxyl groups, which endcapped with octadecyl isocyanate (C19), onto the surface of SiO₂ particles (30 nm) through 3‐glycidoxy‐propyltrimethoxysilane (GPTS) was prepared. The effect of silica‐grafted‐modified Boltorn? H20 on the mechanical properties of polypropylene (PP) was investigated by tensile and impact tests. The morphological structure of impact fracture surface and thermal behavior of the composites were determined by scanning electron microscopy (SEM) and differential scanning calorimetry (DSC), respectively. The melt viscosity of composites was investigated by melt flow index (MFI). The obtained results showed that: (1) the modified Boltorn? H20 was successfully grafted onto the SiO₂ surface confirmed by FT‐IR and X‐ray photoelectron spectroscopy (XPS) analysis; (2) the incorporation of silica‐grafted‐modified Boltorn? H20 (3–5 wt% SiO₂) greatly enhanced the notched impact strength as well the tensile strength of the composites; (3) the incorporation of silica‐grafted‐modified Boltorn? H20 had no influence on the melting temperature and crystallinity of PP phase; (4) the MFI of PP composites increased when the silica‐grafted‐modified Boltorn? H20 particles were added compared with PP/SiO₂ or PP/SiO₂‐GPTS composites. Copyright © 2004 John Wiley & Sons, Ltd.     

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.     

Influence of gamma radiation on the colour strength and fastness properties of fabric using turmeric (Curcuma longa L.) as natural dye

The effect of gamma radiation on the dyeing of cotton with extract of turmeric (Curcuma longa L.) powder has been investigated. Cotton fabric and turmeric powder were irradiated to absorbed doses of 1, 2, 3, 4 and 6 kGy using Co-60 gamma irradiator. Dyeing parameters such as temperature, pH and mordant concentration were optimized. Dyeing was performed using un-irradiated and irradiated cotton with the extracts of un-irradiated and irradiated turmeric powder in order to investigate the effect of radiation treatment on the colour strength of dyed fabric. The reported data of un-irradiated and irradiated fabrics dyed with un-irradiated and irradiated dyes were obtained using the spectraflash SF-650. The colourfastness to light, rubbing- and washing-fastness properties showed that gamma irradiation has improved the dyeing characteristics from fair to good.     

Effect of mercerization and gamma irradiation on the dyeing behaviour of cotton using stilbene based direct dye

The dyeing behaviour of mercerized and gamma irradiated cotton fabric using stilbene based direct dye has been investigated. The fabric was treated with different concentrations of alkali to optimize the mercerization. The optimum mercerized cotton fabric was irradiated to absorbed doses of 2, 4, 6, 8 and 10 kGy using Cs-137 gamma irradiator. Dyeing was performed using irradiated and un-irradiated cotton with dye solutions. The dyeing parameters such as temperature, time of dyeing, pH of dyeing solutions and salt concentration were optimized. The colour strength values of dyed fabrics were evaluated by comparing irradiated and un-irradiated cotton in CIE Lab system using Spectra flash SF650. Methods suggested by International Standard Organization (ISO) were employed to study the effect of gamma irradiation on the colourfastness properties of dyed fabric. It was found that mercerized and irradiated cotton have not only improved the colour strength but enhanced the rating of fastness properties also.     

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.     

Antibacterial properties of Aloe vera gel-finished cotton fabric

In this study, cotton fabrics were finished with Aloe vera gel along with 1,2,3,4-butanetetracarboxlic acid as a crosslinking agent using the pad-dry-cure method. The finished fabrics were characterized by Fourier transform infrared spectroscopy. The infrared spectra confirmed that the active ingredients of A. vera gel attached to the hydroxyl groups of cotton fabric via a carboxylic acid cross-linking agent. The antibacterial activity of A. vera-finished fabrics was qualitatively evaluated by the AATCC-147 method and scanning electron microscopy. It was observed that A. vera gel-finished fabric has much less bacterial adhesion. The A. vera gel-finished [concentration ≥3 % (w/v)] cotton fabric inhibited the growth of both gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria. The mechanism of cell death by A. vera gel was evaluated using transmission electron microscopy (TEM). TEM photographs suggested that the cell death is due to the destruction of the bacterial cell wall. The finished fabric was also evaluated for its performance properties such as tensile strength, crease recovery angle, bending length, etc.     

Electron-Beam-Initiated Grafting of Flame Retardants to Fabrics Containing Cellulose. I. Reaction Rate Studies

Triallyl phosphate (I), bis(β-chloroethyl) vinyl phosphonate (II), and a multi-functional condensate of n were grafted to cotton and rayon fabrics and the grafted products screened for potential flame retardancy. Grafting was initiated by a 48 × 6 in. electron beam, in air, from a 550 kV, 20 mA accelerator powered by an insulated core transformer, with a dose rate of approximately 1 Mrad/sec. The monomers were either copolymerized in untreated fabric with N-methylol acrylamide as a coreactant or were copolymerized with pendant double bonds in fabric that had been acrylamidomethylated in a prior step.     

Synthesis of gold nanoparticles using herbal Acorus calamus rhizome extract and coating on cotton fabric for antibacterial and UV blocking applications

Gold nanoparticles (AuNPs) have been synthesized by greener method using chloroauric acid as precursor and extract of Acorus calamus rhizome as reducing agent. Formation of AuNP was confirmed by the presence of Surface Plasmon Resonance (SPR) peak in UV–Visible spectral analysis. XRD and FT-IR spectral analyses were performed for characterization. SEM images show spherical morphology and HR-TEM images reveal nanosize of AuNPs. The AuNPs were then coated on cotton fabric by pad-dry-cure method and characterized by SEM with EDAX technique. The results reveal the deposition of AuNPs on the surface of cotton fabric. Uncoated cotton, neat extract coated cotton and extract containing AuNPs coated cotton fabrics were then tested for antibacterial activity against Gram positive (Staphylococcus aureus) and Gram negative (Escherichia coli) bacterial strains by AATCC 100 test method. It showed that the extract containing AuNPs coated cotton fabric had higher antibacterial activity than other test samples against E. coli. UV-DRS analysis performed on extract containing AuNPs coated cotton fabric showed improved UV-blocking property than uncoated cotton fabric and neat extract coated cotton fabric.