Facile process for the fabrication of durable superhydrophobic fabric with oil/water separation property

A durable superhydrophobic fabric with oil/water separation property has been successfully prepared by introducing the modified silica nanoparticles and polysiloxane. The as-prepared fabric shows liquid repellency not only to water but also to coffee, milk and tea droplets, which are normal in daily life. Furthermore, the treated fabric shows simultaneous superhydrophobicity and superoleophilicity, which could be utilized as materials to separate oil/water mixture with high efficiency. It is important to note that the obtained fabric kept stable superhydrophobicity even after it suffered severe friction damage. The surface morphologies of untreated/treated fabrics were characterized by the scanning electron microscopy. The chemical compositions were characterized by X-ray photoelectric energy spectroscopy and Fourier transform infrared spectrum. This functionalized fabric will be helpful for developing superhydrophobic and selective oil adsorption materials.     

Modification of cotton fabric by mussel-inspired for oil/water separation

An oil/water separation cotton fabric with high separation efficiency has been successfully developed by combining mussel-inspired one-step copolymerization approach and Michael addition reaction. The cotton fabric was first coated with the adhesive polydopamine (PDA) film by simple immersion in an aqueous solution of dopamine at pH of 8.5. Then n-dodecyl mercaptan (NDM) was conjugated with PDA film through Michael addition reaction at ambient temperature. The chemical structure, surface topography, and surface wettability of the fabric were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy, and contact angle experiments, respectively. The results showed that as-prepared cotton fabric had highly hydrophobicity with the water contact angle of 145° and superoleophilicity with the oil contact angle of 0°. It exhibited desirable property of oil/water separation, and it had excellent potential to be used in practical applications and has created a new field for oil/water separation.     

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.     

Fabrication of hydrophobic/oleophilic cotton fabric by mussel-inspired chemistry for oil/water separation

A straightforward approach was proposed to modify cotton fabric for oil/water separation based on musselinspired reaction. The poly(DMA-Octadecyl acrylate) was designed to contain key chemical constituents present in mussel adhesive proteins by free radical polymerization of dopamine hydrochloride and octadecyl acrylate, which strongly adsorbed to fabric substrates, providing a special surface for fabric. The chemical structure, surface topography, and surface wettability of the fabric were characterized. The results showed that as-prepared cotton fabric displayed a high CA of >150° when dripped water droplets were on the modified fabric surface, and the oil contact angle (OCA) was close to 0°, it had excellent potential to be used in practical applications and has created a new method of fabric modification for oil/water separation.     

Preparation of electrospun silk fibroin/Cellulose Acetate blend nanofibers and their applications to heavy metal ions adsorption

Silk fibroin (SF)/Cellulose Acetate (CA) blend nanofibrous membranes were prepared by electrospinning and their heavy metal absorbabilities were examined in an aqueous solution after ethanol treatment. The electrospun nanofibrous membranes were comprised of randomly oriented ultrafine fibers of 100–600 nm diameters. As a result of field emission electron microscope (FEEM), the anti-felting properties of the blend nanofibrous membranes were markedly improved after treatment with 100 % ethanol when SF was blended with CA. Metal ion adsorption test was performed with Cu²⁺ as a model heavy metal ion in a stock solution. The SF/CA blend nanofiber membranes showed higher affinity for Cu²⁺ in an aqueous solution than pure SF and pure CA nanofiber membranes. Especially, the blend nanofibrous membranes with 20 % content of CA had an exceptional performance for the adsorption of Cu²⁺, and the maximum milligrams per gram of Cu²⁺ adsorbed reached 22.8 mg/g. This indicated that SF and CA had synergetic effect. Furthermore, the parameters affecting the metal ions adsorption, such as running time and initial concentration of Cu²⁺, had been investigated. The results showed that the adsorption of the Cu²⁺ sharply increased during the first 60 min, the amount of metal ions adsorbed increased rapidly as the initial concentration increased and then slope of the increase decreased as the concentration further increased. This study provides the relatively comprehensive data for the SF/CA blend nanofibrous membranes application to the removal of heavy metal ion in wastewater.     

Fabrication of superhydrophobic cellulose/chitosan composite aerogel for oil/water separation

Superhydrophobic cellulose and chitosan composite aerogel (SCECS) is fabricated through a novel and simple approach for the first time. During the preparation of cellulose and chitosan composite aerogel (CECS), chitosan is selfassemble into number micron-diameter particles on the surface of aerogel, which is similar to the micromorphology of a lotus leaf. Based on the rough surface, CECS is modified by sodium stearate through electrostatic interaction and ion exchange. Water contact angles of 156° are obtained for superhydrophobic aerogel. SCECS can remove various oils from water and with absorption capacities of 10 g/g for oil. Furthermore, the special structure of a non-porous of surface and porous layer of internal is benefit to separate surfactant-stabilized water-in-oil emulsions under gravity.     

Effect of Urea/NaOH aqueous system on morphology and properties of cotton fabric

This paper was focused on comparing the effect of urea/NaOH aqueous system with that of single urea or NaOH treating system on cotton fabric morphology and properties. Optical microscopy (OM), scanning electron micrograph (SEM), Fourier transform infrared spectroscopy (FT-IR), and wide X-ray diffraction (WAXD) were used to study cotton fabric morphology and properties before and after treatment by urea/NaOH, single urea, and single NaOH treating systems. Results showed that the cotton fabric treated by urea/NaOH aqueous system had better dyeability than the samples untreated and treated by single urea or single NaOH treating systems. Obvious differences were observed in appearance and morphology of cotton fabrics before and after treatment by urea/NaOH aqueous system. The composition and the structure of urea/NaOH treated cotton fiber had no distinct changes, only except the reduced hydrogen bonding between cellulosic macromolecules. Tensile strength and elongation at break of cotton fabric showed a slight decrease after treatment by urea/NaOH system. In addition, shrinkage of area and weight reduction of urea/NaOH treated samples were higher than those of the samples untreated and treated by single urea or single NaOH treating system.     

Ternary carboxymethyl chitosan-hemicellulose-nanosized TiO<Subscript>2</Subscript> composite as effective adsorbent for removal of heavy metal contaminants from water

A ternary composite consisting of carboxymethyl chitosan, hemicellulose, and nanosized TiO₂ (CHNT) was prepared by incorporating TiO₂ nanoparticles into the pre-synthesized carboxymethyl chitosan-hemicellulose polysaccharide network. The microstructure and chemical composition of the obtained CHNT was characterized by TEM, SEM, FTIR, and TGA. The adsorption of some toxic heavy metals including Ni(II), Cd(II), Cu(II), Hg(II), Mn(VII), and Cr(VI), onto the as-prepared CHNT composite was investigated. The effects of pH, temperature and contacting time on the adsorption process were studied. Results revealed that the CHNT composite exhibited efficient adsorption capacity of the above metal ions from aqueous solution due to its favorable chelating groups in structure. The adsorption process was best described by the pseudo-second-order kinetic model, while isotherm modeling revealed that the Langmuir equation better described the adsorption on CHNT as compared to Freundlich model. Moreover, the CHNT loaded metal ions can be easily regenerated with EDTA and reused repeatedly up to five cycles. The environmental friendly hybrids were expected to be a promising candidate for future practical application in heavy metal contaminated water treatment.     

Novel one bath application of oil and water repellent finish with environment friendly cross-linker for cotton

The performance of the fluorocarbon based acrylate polymer, Genguard, was evaluated on cotton fabric. Genguard treated fabric exhibited good oil and water repellency rating before washing. However, rating was lost immediately after washing. In order to enhance the washing durability of the Genguard finish, citric acid was incorporated into the recipe as a formaldehyde free cross-linker. The combination of citric acid with fluorocarbon exhibited good improvement in the durability of the oil and water repellency rating after multiple washings. In addition, fabric treated with this novel combination demonstrated excellent increase in the easy care performance. Scanning electron microscope (SEM) was used to examine the surface of the fabric treated with Genguard and citric acid as a cross-linker.     

Ultrasound for efficient emulsification and uniform coating of an anionic lubricant on cotton

In this paper, a softener of aliphatic acid ester was treated with an ultrasonic bath and coated on cotton. The particle size distribution of the softener in water was evaluated by a particle size analyzer. Physical and surface properties of the fabric after coating with the ultrasonic treated softener were compared with a control sample. Different technical measurements were utilized for this purpose including bending lengths measurement (BLM), friction coefficient measurement (FCM), evaluation of crease recovery angle (CRA), moisture regain measurement (MRM), evaluation of contact angle (CA), reflectance spectroscopy (RS), atomic force microscopy (AFM) and scanning electron microscopy (SEM). Results showed that ultrasound enhances softener distribution in water and it improves the drapeability, friction behavior, wrinkle recovery and water repellency of cotton due to uniform coating of softener.     

Study on antibacterial and comfort performances of cotton fabric finished by chitosan-silver for intimate apparel

The fabric used for intimate apparel is widely required to have excellent antibacterial and comfort performances. In order to improve its antibacterial ability, this paper studied chitosan-silver finishing on the cotton knitted fabric. The study indicates that the chitosan-silver attached to the fabric exhibits excellent antibacterial action against the typical bacteria of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureu). The anti-bacterial mechanism of chitosan-silver against E. coli and S. aureu were investigated. To guarantee its prominent comfort performance, measurements were made on the finished fabric of its air permeability, water vapor transmission, hydrophily, surface friction and bending ability against the control fabric, which is currently used for intimate apparel. The antibacterial and comfort performances were compared between the tested fabrics. The results show that the air permeability and the hydrophily of the finished cotton fabric are significantly better than the control one, while the water vapor transmission, the surface friction and the adjustable rate remain similar to each other. The bending rigidity of the finished fabric is slightly better due to the attachment of chitosan within accepted threshold. The dual compounding theory of chitosan-silver proves to be useful for a higher synergistic effect of anti-bacteria, lower whiteness degradation and overall optimization of comfort performance. This dual compounding theory of chitosan-silver is valuable for improving antibacterial and comfort performances of intimate apparel.     

Use of amino-modified cotton fibers loaded with copper ions for anionic dye removal under batch and fixed-bed systems: A comparative study

Amine-functionalized supports were prepared by chemical modification of cotton fibers using amino compounds namely diethylenetriamine (DET) and 1,4-diaminobutane (DB) in order to be loaded with copper ions. Evidence of attaching amine groups onto cellulosic fibers was confirmed through nitrogen and SEM analysis. Adsorption behavior of Acid Blue 25 from aqueous solutions onto [Cu(II)/DET-cotton] and [Cu(II)/DB-cotton] has been evaluated via batch and column mode systems. During the batch experiments, the effects of temperature and type of adsorbent on dye removal were investigated. Results revealed the formation of ternary complexes of the type [AB25/Cu(II)/adsorbent] with a [5/2:3:1] stoichiometry for DET-cotton and a [1:1:1] stoichiometry for DB-cotton at 20 °C. In the isotherm studies, Langmuir, Freundlich, and Jossens equations were applied and it was found that the experimental data conformed to Jossens model. Thermodynamic parameters such as change in free energy (ΔG ⁰), enthalpy (ΔH ⁰), and entropy (ΔS ⁰) have also been calculated in this paper, and it was found that the adsorption process was exothermic and spontaneous. The column experiments were conducted to study the effect of bed height on adsorption performance of both adsorbents. Results exhibited that the column capacity of [Cu(II)/DET-cotton] complex was found to be higher than that of [Cu(II)/DB-cotton] as was obtained in batch process. BDST model was applied to experimental data in order to predict the breakthrough curves and determine the characteristics parameters of the column useful for process design. Results revealed that the used model was appropriate to fit the experimental data. Desorption studies to recover the adsorbed dye from both adsorbents were performed with NaOH and NH₄Cl solutions.     

Effect of various shapes of zinc oxide nanoparticles on cotton fabric for UV-blocking and anti-bacterial properties

Various shapes of ZnO — multi-petals, rod and spherical — were prepared and then applied on cotton fabric for UV-blocking and anti-bacterial properties. The ZnO particles were investigated by XRD and SEM. The as-prepared suspension was applied onto cotton fabrics via the pad-dry-cure process at 150 °C. The characteristics of the fabric coating were investigated by SEM, XRD and Atomic Absorption Spectroscopy (AAS). The UV-blocking effectiveness was measured with a UV-Vis spectrophotometer whilst the antibacterial activity was determined using the AATCC 147 method. The results of XRD and SEM on the ZnO powders show that we can produce various shapes of ZnO. The investigation by SEM and AAS clearly revealed that ZnO was effectively deposited on the cotton surface and that the adhesion was retained after washing ten cycles. The sphericals-shaped ZnO and multi-petals shaped ZnO coated fabrics show excellent UV-blocking properties. All treated samples showed good antibacterial activity against Staphylococcus Aureus. The shape of ZnO shows no considerable effect on antibacterial properties.     

Effects of planting system,plant density and flower removal on yield and quality of hybrid seed in cotton

Seedling transplanting and plastic mulching are widely adopted intensive planting systems in cotton production in China. Manual removal of early- or late-season flowers may improve seed quality without sacrificing yield through the compensatory growth of cotton plants. Two experiments were conducted, in Yellow River Valley in China from 2002 to 2003, to test if the intensive systems and flower removal can be used for enhancing hybrid seed production. Results in the first experiment show that yields of seed cotton and seed, and seed quality parameters averaged across three plant densities (2.25, 3.00 and 3.75 plants/m²), were significantly improved by either transplanting or plastic mulching relative to conventional planting. The improvements in yield and quality in two intensive planting systems were mainly attributed to longer and earlier flowering period. Transplanted plants did not differ significantly from mulched plants in seed yield, seed maturity and percentage germination, but transplanting decreased lint percentage and increased seed index relative to mulching. In terms of seed yield and quality, the optimum plant density for each planting system was 3.00 plants/m². At the optimum plant density, seed yields averaged across two years for transplanting and mulching systems were 31.3% and 32.6% higher than for conventional planting system, respectively. Flower removal did not significantly affect seed yield, but removal of late-season or both early- and late-season flowers significantly improved seed quality. It was concluded that transplanting or plastic mulching, low plant density (3.00 plants/m²), and removal of late-season or both early- and late-season flowers can be integrated to enhance yield and quality of hybrid seed of cotton.     

Surface treatments of jute fabric: The influence of surface characteristics on jute fabrics and mechanical properties of jute/polyester composites

In this study, jute fabrics were modified by alkali, micro-emulsion silicon (MS) and fluorocarbon based agents (FA) in order to enhance the interfacial adhesion between the polyester matrix and the jute fiber. X-ray photoelectron spectroscopy (XPS) and contact angle measurements were used to characterize fiber surfaces. The effects of various surface treatments on the mechanical and morphological of jute/polyester composites were also studied. All surface treatments were shown to improve the tensile, flexural strengths and interlaminar shear strengths of the composites. Moreover, the maximum improvement in the mechanical properties was obtained for the FA treated jute/polyester composites. SEM micrographs of the tensile fracture surface of jute/unsaturated polyester composites also exhibited improvement of interfacial and interlaminar shear strengths by the alkali, MS and FA treatments of jute fibers.     

新疆南疆棉花“滴水出苗”技术问题及建议

分析了新疆南疆棉花“滴水出苗”技术中存在的主要问题,并从提高整地质量、做好土壤封闭、整地速度与播种速度相适配、规范播种作业质量、播种后及时铺管滴水、确保滴灌压力均匀一致、适量滴水等方面提出了技术建议,旨在推动棉花“滴水出苗”技术在南疆的推广应用,缓解新疆南疆耕作区春季用水紧张。     

Study of gene effects for cotton yield and Verticillium wilt tolerance in cotton plant (Gossypium hirsutum L.)

Verticillium wilt (VW), caused by Verticillium dahliae Kleb., is a destructive disease of cotton (Gossypium hirsutum L.). The use of resistant cultivars has long been considered the most practical and effective mean of control. The aim of this work was to study the quantitative genetic basis of Verticillium wilt resistance in Upland cotton by using five genotypes and their possible crosses without reciprocals selecting simultaneously for resistance and desirable agronomic characteristics. Five cotton cultivars and 10 F1s from half-diallel crosses were analyzed for VW resistance. The seed cotton yield, the number of bolls/ plant, and boll weight were measured and Verticillium wilt index (VWI) was estimated during two crop seasons in two different sites each year always on plots with naturally infested soil. Genetic components of variance were analyzed using the Hayman model. Analysis of variance for all characters showed significant differences between genotypes, without genotype-site interaction in most cases. Both, additive genetic variance component (D) and dominance genetic variance components (H1 and H2) were presented in all characters, except for VWI. D was the most important component for boll weight and VWI. Boll weight was the most correlated character with seed cotton yield and VWI. Broad sense heritability was high for boll weight and VWI, moderate for seed cotton yield and low for bolls per plant. Narrow sense heritability was moderate for boll weight, and high for VWI.     

Sonicator dyeing of modified cotton, wool and silk with Mahonia napaulensis DC. and identification of the colorant in Mahonia

Mahonia napaulensis DC. (local name—Taming) family Berberidaceae, produces natural dye from its stem which has been used for dyeing textiles by the Apatanis (a tribe of Arunachal Pradesh) since ancient times. Sonicator dyeing with Mahonia napaulensis showed marked improvement in dye uptake. It showed that pretreatment with metal mordant (2%, w/w with respect to the fabric) improved substantially the fastness properties for dyed cotton, silk fabrics and wool yarn. Five fractions were isolated from column chromatography of the stem extract of Mahonia. Attempts have been made to identify these fractions by matching the spectral data which indicated that they were from a well-known isoquinoline alkaloid family.     

Effect of trans-Bacillus thuringiensis gene on gibberellic acid and zeatin contents and boll development in cotton

Two experiments were conducted to investigate the effect of the Bacillus thuringiensis (Bt) transgene on gibberellic acid and zeatin contents and boll development in cotton using two types of Bt-transformed cultivars. In the 2003 study, boll size and weight, gibberellic acid 3 (GA₃) and zeatin (ZR) contents were investigated from 3 to 45 days after flowering (DAF). In 2004, the flowers were sprayed with GA₃, 6-benzyl adenine (6-BA) or a combination of both, and responses in boll size and weight, and endogenous GA₃ and ZR contents were determined. In comparison to the common parent, Simian 4, overall boll size and weight were lower for the conventional Bt cultivar, Sikang 1, but higher for the hybrid Bt cultivar, Sikang 3. Similarly, the boll GA₃ and ZR contents of Sikang 1 were lower than those of Simian 4, while those of Sikang 3 were higher than Simian 4. The largest difference between Sikang 1 and Simian 4 for boll GA₃ and ZR contents were 18.5 and 25.5%, respectively, observed at 17 DAF. The largest difference between Sikang 3 and Simian 4 for boll GA₃ and ZR contents were 25.5 and 85.7% at 31 DAF respectively. Application of GA₃, 6-BA or a combination significantly increased boll size and weight for the conventional Bt cultivar and Simian 4, but did not have a significant effect on these characteristics of the hybrid cultivar Sikang 3. GA₃ and ZR contents of the conventional Bt cultivar Sikang 1 were also significantly increased by application of these treatments. The combined application of GA₃ and 6-BA tended to have a larger effect than the application of either of them separately, but the differences were statistically not significant. These results suggested that the lower boll GA₃ and ZR contents, which could reduce boll nitrogen metabolism intensity, were responsible for the reduced boll development of the conventional Bt cultivar Sikang 1.     

Seed and oil yields of Moringa oleifera variety Periyakalum-1 introduced for oil production in four ecosystems of South America

Moringa oleifera Lam. is a member of Moringaceae family which grows throughout most of the tropics, and is native to sub-Himalayan tracts of north west India, Pakistan, Bangladesh and Afghanistan. Moringa seed concentrates 35-45% oil which is considered a great natural cosmetic emollient almost total natural absence of color and odor, and high oleic acid concentration (>73%). To assess their production potential in the Arid Chaco, The Yungas Tropical Forest, Tropical Lowland Forest, and in the Sub-Humid Chaco Ecosystems of South America, a comparative trial was undertaken to determine their seed yield and oil content. Arid Chaco Ecosystem: significant (P < 0.05) difference in seed yields among years were found, with 176.17 and 481.25 kg/tree recorded for 1- and 2-year-old trees, respectively. Sub-Humid Chaco Ecosystems: the difference in seed yield and oil percentage between years was significant (P < 0.05). Comparison between years showed significantly (P < 0.05) higher seed yields, and significantly (P < 0.05) lower oil percentage for the two years old trees, than for the one year old trees. The oil/tree content was significantly (P < 0.05) higher for two years old trees than for one-year-old trees. Yungas Tropical Forest Ecosystem: seed oil percentage was significant (P < 0.05) higher in one-year-old trees than in seeds of two years old trees. Overall: over the tree years, oil percentage was significantly (P < 0.05) higher for seeds produced at the Arid Chaco than at the Sub-Humid Chaco. The seed/tree yields and the oil/tree content were no significantly (P < 0.05) different among the three ecosystems. However, when oil percentage per tree and seed yield/tree were combined trees from Sub-Humid Chaco and from Yungas Tropical Forest yielded significantly (P < 0.05) higher oil content compared to that from Arid Chaco trees.