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.     

Interpenetrating polymer networks of poly(dimethyl siloxane–urethane) and poly(methyl methacrylate)

Simultaneous IPNs of poly(dimethyl siloxane-urethane) (PDMSU)/poly(methyl methacrylate) (PMMA) and related isomers have been prepared by using new oligomers of bis(β-hydroxyethoxymethyl)poly(dimethyl siloxane)s (PDMS diols) and new crosslinkers biuret triisocyanate (BTI) and tris(β-hydroxylethoxymethyl dimethylsiloxy) phenylsilane (Si-triol). Their phase morphology have been characterized by DSC and SEM. The SEM phase domain size is decreased by increasing crosslink density of the PDMSU network. A single phase IPN of PDMSU/PMMA can be made at an M_c = 1000 and 80 wt % of PDMSU. All of the pseudo- or semi-IPNs and blends of PDMSU and PMMA were phase separated with phase domain sizes ranging from 0.2 to several micrometers. The full IPNs of PDMSU/PMMA have better thermal resistance compared to the blends of linear PDMSU and linear PMMA. © 1993 John Wiley & Sons, Inc.     

Corrosion studies and interfacial bonding of urea/poly(dimethylsiloxane) sol/gel hydrophobic coatings on AA 2024 aluminum alloy

Bis[(ureapropyl)triethoxysilane] bis(propyl)-terminated-polydimethylsiloxane 1000 (PDMSU), an organic-inorganic hybrid, diluted in either EtOH or a mixture of EtOH-PrOH, was used in thin film form (<200 nm) to inhibit the corrosion of AA 2024 alloy. Potentiodynamic, time-dependent cyclovoltammetric measurements and salt spray tests showed that the corrosion inhibition of the latter was 10 times higher than that of the former films. This was correlated with the higher degree of hydrolysis and the formation of more open polyhedral silsesquioxane species (T2) in the bulk heat-treated PDMSU/EtOH-PrOH xerogels (29Si NMR spectra). The structure of the coatings deposited on AA 2024 Al alloy was deduced from the infrared reflection-absorption (IR RA) spectra, which revealed more extensive urea-urea interactions and more efficient silane-Al interface bonding for the PDMSU/EtOH-PrOH coatings with higher corrosion inhibition. Ex situ IR RA potentiodynamic spectroelectrochemical measurements of PDMSU coatings revealed that their degradation did not proceed via the formation of silanol groups and consequent hydration of the coatings but that they decomposed above E(corr) by forming fragments composed of -CH2- segments in an all-trans conformation.     

Diblock-copolymer-coated water- and oil-repellent cotton fabrics

A diblock copolymer consisting of a sol-gel-forming block and a fluorinated block was used to coat cotton fabrics, yielding textiles that were highly oil- and water-repellent. The coating procedure was simple. At grafted polymer amounts of as low as 1.0 wt %, water, diodomethane, hexadecane, cooking oil, and pump oil all had contact angles surpassing 150° on the coated cotton fabrics and were readily rolled. The liquids were not drawn into the interfiber space by the coated fabrics. Rather, droplets of the nonvolatile liquids such as cooking oil retained their beaded shapes for months with minimal contact angle changes. When forced into water, the coated fabrics trapped an air or plastron layer and this plastron layer was stable for months. In addition, the coating had high stability against simulated washing, and the mechanical properties were essentially identical to those of uncoated cotton fabrics.     

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.     

UV protective textiles by the deposition of functional ethylcellulose nanoparticles

Ethylcellulose (EC) nanoparticles have been widely investigated for their use as drug delivery systems. However, their application on the textile field has been hardly studied. In this work, the use of EC nanoparticles as nanocarriers of active or lipid soluble compounds and their subsequent deposition on cotton textile is proposed in order to obtain functional textiles. A UV protective textile has been obtained after deposition of EC nanoparticles loaded with a liposoluble UV filter on cotton fabrics. The EC/cotton affinity and the attachment mechanism of EC nanoparticles on cotton substrate was studied by means of thermal behaviour evaluation, estimation of adhesion work (W_A) and wash resistance tests. It is proposed that during EC nanoparticles deposition on cotton fabric, entanglement of polymeric chains is favoured, thus improving adhesion of EC nanoparticles on cotton substrate. The functionality of cotton textile was assessed by ultraviolet protection factor (UPF) measurements, showing a high UPF value (UPF = 45). Evaluation of UPF as a function of washing cycles were carried out on treated cotton fabrics. Washed fabrics still provided good UV protection (UPF ≥ 25), evidencing the presence of nanoparticles after washing cycles and the durability of the conferred functionality.     

Durable,water-cleanable,superhydrophilic coatings for oil/water separation under harsh conditions

A simple, economical, and efficient method for fabricating stable hydrophilic/underwater superoleophobic coating under harsh conditions remains a significant challenge. Here, by the hydrolysis of 3-(Methacryloyloxy) propyltrimethoxysilane (TMSPMA) on cotton fabric and the free radical polymerization of [2-(Methacryloyloxy) ethyl] dimethyl-(3-sulfonic acid propyl) ammonium hydroxide (SBMA) and TMSPMA, a superhydrophilic coating was fabricated. The coating can withstand harsh environments, such as strong acid and alkali. In addition, the coated cotton fabrics show an effective separation of surfactant-stabilized oil-in-water emulsions with extreme flux as high as 1500 Lm^?2 h^?1 only under gravity. Importantly, the oil-contaminated coated cotton fabrics can be cleaned only by water washing. The outstanding properties of the coating including durability, recyclability and resistance to harsh environment, highlight its practical application in emulsion separation and oily wastewater purification.     

Multifunctionalization of cotton through in situ green synthesis of silver nanoparticles

A convenient method for in situ synthesis of silver nanoparticles was developed to realize the multifunction of cotton. The silver nanoparticles were obtained through reduction of silver ions by cotton under basic condition at room temperature. The as-synthesized silver nanoparticles achieved the coloration of cotton fibers. Heating increased the color strength of cotton fibers with silver nanoparticles. Mercerization treatment as a common finishing process enhanced the properties of cotton fibers modified by silver nanoparticles. The mercerized cotton exhibited brighter color and had very good colorfastness to washing. The cotton fibers treated with in situ synthesized silver nanoparticles possess strong antibacterial activity with excellent washing durability.     

N-halamine biocidal coatings via a layer-by-layer assembly technique

Two N-halamine copolymer precursors, poly(2,2,6,6-tetramethyl-4-piperidyl methacrylate-co-acrylic acid potassium salt) and poly(2,2,6,6-tetramethyl-4-piperidyl methacrylate-co-trimethyl-2-methacryloxyethylammonium chloride) have been synthesized and successfully coated onto cotton fabric via a layer-by-layer (LbL) assembly technique. A multilayer thin film was deposited onto the fiber surfaces by alternative exposure to polyelectrolyte solutions. The coating was rendered biocidal by a dilute household bleach treatment. The biocidal efficacies of tested swatches composed of treated fibers were evaluated against Staphylococcus aureus and Escherichia coli. It was determined that chlorinated samples inactivated both S. aureus and E. coli O157:H7 within 15 min of contact time, whereas the unchlorinated control samples did not exhibit significant biocidal activities. Stabilities of the coatings toward washing and ultraviolet light exposure have also been studied. It was found that the stability toward washing was superior, whereas the UVA light stability was moderate compared to previously studied N-halamine moieties. The layer-by-layer assembly technique can be used to attach N-halamine precursor polymers onto cellulose surfaces without using covalently bonding tethering groups which limit the structure designs. In addition, ionic precursors are very soluble in water, thus promising for biocidal coatings without the use of organic solvents.     

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.     

Sol–gel coating of cellulose fibres with antimicrobial and repellent properties

Multifunctional, water and oil repellent and antimicrobial finishes for cotton fibres were prepared from a commercially available fluoroalkylfunctional water-born siloxane (FAS) (Degussa), nanosized silver (Ag) (CHT) and a reactive organic–inorganic binder (RB) (CHT). Two different application procedures were used: firstly, one stage treatment of cotton fabric samples by FAS sol (i), as well as by a sol mixture constituted from all three precursors (Ag–RB–FAS, procedure 1S) (ii), and secondly, two stage treatment of cotton by Ag–RB sol and than by FAS sol (Ag–RB + FAS, procedure 2S) (iii). The hydrophobic and oleophobic properties of cotton fabrics treated by procedures (i)–(iii) before and after consecutive (up to 10) washings were established from contact angle measurements (water, diiodomethane and n-hexadecane) and correlated with infrared and XPS spectroscopic measurements. The results revealed that even after 10 washing cycles cotton treated with Ag–RB + FAS (2S) retained an oleophobicity similar to that of the FAS treated cotton, while the Ag–RB–FAS (1S) cotton fibres exhibited a loss of oleophobicity already after the second washing, even though fluorine and C–F vibrational bands were detected in the corresponding XPS and IR spectra. The antibacterial activity of cotton treated by procedures (i)–(iii) was tested by its reduction of the bacteria Escherichia coli and Staphylococcus aureus following the AATCC 100-1999 standard method and EN ISO 20743:2007 transfer method. The reduction in growth of both bacteria was nearly complete for the unwashed Ag–RB and Ag–RB–FAS (S1), but for the unwashed Ag–RB + FAS (S2) treated cotton no reduction of S. aureus and 43.5 ± 6.9% reduction of E. coli was noted. After the first washing, the latter two finishes exhibited nearly a complete reduction of E. coli but for the Ag–RB treated cotton the reduction dropped to 88.9 ± 3.4. None of the finishes retained antibacterial properties after 10 repetitive washings. The beneficial and long-lasting low surface energy effect of FAS finishes in the absence of Ag nanoparticles, which led to the “passive” antibacterial properties of FAS treated cotton fabrics, was established by applying the EN ISO 20743:2007 transfer method. The results revealed a reduction in bacteria of about 21.9 ± 5.7% (FAS), 13.1 ± 4.8% (Ag–RB–FAS (S1)) and 41.5 ± 3.7% (Ag–Rb + FAS (S2)), while no reduction of the growth of bacteria was observed for cotton treated with Ag nanoparticles after 10 repetitive washings. The physical properties (bending rigidity, breaking strength, air permeability) of finished cotton samples were determined, and showed increased fabric softness and flexibility as compared to the Ag–RB treated cotton, but a slight decrease of breaking strength in the warp and weft directions, while air permeability decreased for all type of finishes.     

Surface modification of cellulose with plant triglycerides for hydrophobicity

Hydrophobic cotton was achieved by surface modification of the cellulose with triglycerides from several plant oils including soybean, rapeseed, olive and coconut oils. These oils were delivered to the cellulose substrates in homogeneous solutions of ethanol or acetone as well as aqueous emulsions. Surface modification was facilitated by solvent evaporation followed by heating between 110 and 120 °C for 60 min. All oils, except for coconut, produced hydrophobic and less water-absorbing cotton, supporting the desirable role of higher unsaturation in the fatty acids to achieve crosslinked network. The most hydrophobic surfaces were obtained by the reaction with 1% soybean oil in acetone. On both bleached and scoured cotton, a water contact angle of 80° and water absorption value of 0.82 μL/mg were achieved. The acquired hydrophobicity was not only retained after water washing but also improved with subsequent exposures to elevated temperatures. The surface tension of scoured cotton cellulose was lowered from 63.81 mJ/m² to 25.74 mJ/m² when modified by soybean oil delivered in acetone, which is lower than that of poly(ethylene terephthalate). An aqueous emulsion of soybean oil also rendered the scoured cotton hydrophobic, which shows promise for a green chemistry and bio-based approach to achieve water repellency on cellulosic materials.     

含杀菌、吸附双功能基棉纤维的制备与性能

化学改性;吸附剂;杀菌剂;含杀菌、吸附双功能基棉纤维的制备与性能     

Hydrorepellent finishing of cotton fabrics by chemically modified TEOS based nanosol

Hydrorepellency was conferred to cotton fabrics by an hybrid organic–inorganic finishing via sol–gel. The nanosol was prepared by co-hydrolysis and condensation of tetraethoxysilane (TEOS) and 1H,1H,2H,2H–fluorooctyltriethoxysilane (FOS), or hexadecyltrimethoxysilane (C₁₆), as precursors in weakly acid medium. The application on cotton was carried out by padding with various impregnation times, followed by drying and thermal treatment, varying the FOS add-on from 5 till 30 % on fabric weight or C₁₆ add-on from 5 to 10 %. Treated samples were tested in terms of contact angles, drop absorption times, washing fastness and characterized by SEM, XPS and FTIR-ATR analyses. In the case of FOS modified nanosol applied with an impregnation time of 24 h or C₁₆ modified nanosol, water contact angles values very close or even higher than 150° were measured, typical of a superhydrophobic surface. The application of the proposed sol–gel process yielded also a satisfactory treatment fastness to domestic washing, in particular for FOS modified nanosol.     

Hydrophobicity modification of woven cotton fabric by hydrophobic fumed silica coating

Water repellency of woven cotton fabric was achieved by coating with the aqueous dispersion containing organosilane agent (HDTMS) and fumed silica. The coating agents were applied using padding method and then followed by batching the coated fabric at the ambient temperature for 24 h to allow the condensation reaction between HDTMS silanol group and fumed silica silanol group, rendering silica particles hydrophobic. An ultrasonicator was employed to prepare the homogenous coating dispersion. The water repellency evaluated by water contact angle determination which showed the contact angle over 110° was obtained with low amount of applied HDTMS of 1 wt%. The effect of fumed silica addition on an increase in fiber surface roughness geometry showed the influential result in improving the water contact angle. From durability to washing test, the hydrophobic coatings evidenced from SEM and ATR/FTIR remained adhering to fiber surface, indicating the durability. After washing, the coating on the fabric with fumed silica addition appeared to be scatter particles which made a contribution to the higher contact angle value when compared to sheet-like layer coating in case of HDTMS coating alone.     

Determination of mepiquat chloride residues in cotton and soil by liquid chromatography/mass spectrometry

A liquid chromatographic/mass spectrometric (LC/MS) method is reported for the determination of the onium-type plant growth regulator mepiquat chloride in cotton and soil. The pesticide was extracted from the sample with ethanol and water containing 2% NH4Cl. The extract was cleaned up on a solid-phase extraction C18 column, and the pesticide was determined by LC/MS. The average recoveries were 85.9-93.8, 81.3-91.7, and 78.1-94.7%, with corresponding relative standard deviations of 3.4-9.6, 3.7-12.3, and 4.0-9.8%, from soil, cotton leaves, and cotton seeds, respectively. A coefficient of determination of R2 = 0.9964 was obtained for the analyte calibration graph, from 0.05 to 100 microg/mL. Decision limits, CCalpha, and detection capability, CCbeta, were calculated. Electrospray ionization LC/MS in the positive-ion mode (ESI+) was used to detect mepiquat chloride in extracts of soil, cotton leaves, and cotton seeds. The ion at m/z 114 in the mass spectrum was monitored.     

Admicellar polymerization of styrene on cotton

Thin-film coating on cotton by the admicellar polymerization process was investigated. In this work, styrene was used as the monomer to coat styrene on cotton. The effects of surfactant, styrene, initiator, and electrolyte concentrations on the polymerization process were determined. The polystyrene film formed was characterized by SEM, FTIR, and GPC. The increase in the hydrophobicity of the treated cotton surface was determined by the drop test. Results show that polystyrene thin film was successfully formed on cotton, resulting in cotton that can resist wetting by a water droplet for longer than 30 min.     

Helical concept of the fine structure of cellulose

The helical concept of the fine structure of cellulose as proposed by Manley is discussed. The deuterium exchange experiments with cotton, cotton crystallites, and regenerated cellulose I, in which accessibility was determined by comparing the ratio of the infrared absorbance of the O? D peak to the O? H peak, revealed that the accessibility of cotton linters decreased on acid hydrolysis, whereas it increased on treatment with ethylamine followed by washing with water. This is in contrast to the finding of Manley, who had evaluated the accessibility by a gravimetric D₂O exchange method and had come to the conclusion that acid hydrolysis did not change the accessibility of cellulose and hence cellulose did not contain crystalline and amorphous phases but was all crystalline. On the basis of Manley's protofibril and the accessibility data obtained in this investigation, a concept of the fine structure of cellulose is proposed, in which the role of Manley's protofibril is analogous to the role of individual molecule in the fringe micellar model. This concept explains the properties of cellulose that are otherwise explainable on the currently accepted fringe micellar theory. In addition, it explains the marked shrinkage in the length of cotton and rayon fibers when placed in 16% sodium hydroxide solution.     

A simple test method for measuring water vapor resistance of porous polymeric materials

A simple test method is proposed for measuring water vapor resistance of fabrics. A piece of cotton fabric connected to a container filled with distilled water through a plastic tube was used on a hot plate to generate a saturated water vapor condition on one side of the sample. The temperature of the cotton fabric (approximation of human skin covered with sweat) was measured by a thermocouple. The water vapor resistance of the sample was determined based on the water vapor pressure gradient across the sample and the heat flux. Five types of textile fabric laminated to PU/TPU membranes, plus one type of conventional fabric, were tested by using this simple apparatus as well as the sweating guarded hot plate instrument. The results showed that good agreement was observed between these two test methods. In addition, the surface temperature of the cotton ‘skin’ varied with different fabrics. This is in accordance with the actual intended situation, i.e., the skin temperature of the body is related to the ability of clothing materials to transfer water vapor. Therefore, this simple test apparatus better simulates real-life conditions than the sweating guarded hot plate instrument.     

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。