Development of moisture vapour permeable waterproof cotton fabric by coating with blend of natural rubber latex and polyvinyl alcohol

Cotton fabric was coated with aqueous dispersion containing blend of natural rubber latex (NRL), polyvinyl alcohol (PVA) and starch following a knife-over-roll technique to produce moisture vapour permeable waterproof coating. Coating of cotton with a formulation containing NRL, 15% aqueous PVA and tamarind kernel seed powder as starch, in the ratio of 1:3: 0.3 in presence of a typical sulphur curing system, followed by drying of the coated fabric at 95 °C for 5 min and subsequent vulcanization at 120 °C for 2 h produced most balanced improvements in the properties of the coated fabric such as, waterproofness, breathability as revealed by moisture vapour transmission rate, coating adhesion, tensile properties, abrasion resistance and flex endurance. Incorporation of PVA makes the coating permeable to moisture vapour and such property is promoted further in presence of starch in the coating formulation. Examination of surface morphology of vulcanized coating by scanning electron microscopy revealed that poly vinyl alcohol crystals formed clusters of dimensions of only few microns in the rubber matrix. Such clusters of PVA served as conduits for transportation of moisture vapour through the film of NRL while acting as an effective barrier to liquid water droplets.     

Silver‐containing sol–gel coatings on textiles: antimicrobial effect as a function of curing treatment

Textiles coated with inorganic SiO₂ layers containing silver nanoparticles were prepared using the sol–gel process. The formation of silver particles was investigated as a function of curing treatment variables performed after the coating procedure. The formation of silver particles in nanometre scale was determined with transmission electron microscopy (TEM). The optical properties of coated textiles were investigated using UV/Vis‐spectroscopy under arrangement of diffuse reflectance conditions, and the release of silver from coated textiles was determined with ICP‐spectroscopy. Under the chosen conditions, the formation of embedded silver clusters requires a curing treatment at a minimum temperature of 150°C. The silver‐containing inorganic coatings inhibit the growth of fungi (Aspergillus niger) and bacteria (Bacillus subtilis and Pseudomonas putida) on the coated textiles. The antimicrobial effect depends more on the temperature used for curing treatment and less on the duration chosen for the treatment of textiles after coating. Conditions for application between 150°C and 180°C are commensurate with those used in commercial textile finishing, so the process presented here could be easily adapted to the production of textiles with antimicrobial effects.     

In-situ synthesis of CuO nanoparticles on cotton fabrics using spark discharge method to fabricate antibacterial textile

In this research, the spark discharge method (SDM) was used for in-situ synthesis of copper and copper oxide nanoparticles (NPs) on cotton fabrics for producing antibacterial textile. Varieties of analytical techniques were applied for the characterization of both NPs and synthesized CuO NPs on cotton fabrics. The structural characterization of the particles was carried out by the X-ray powder diffraction method. Also, the morphological properties of treated cotton samples were investigated using scanning electron microscope. Particle size and size distribution were measured by dynamic light scattering apparatus. The results show that concentration of 100 ppm is enough for killing 10⁶ CFU/mL of bacteria. It is indicated that the synthesized CuO NPs are very strong against both Staphylococcus aureus and Escherichia coli. Also, the durability of antibacterial efficiency after 15 times of washing was tested. The results confirm that the antibacterial fastness properties are significant and no colonies spread over agar plate after 15 cycles of washing. It was concluded that SDM for in-situ synthesize of nano-CuO on cotton fabrics in batch systems is very promising method.     

Evaluation of dermal toxicity of antibacterial cotton textile coated by sol-gel technology

This paper reports about cotton textile modification by sol-gel technology with the purpose of obtaining antibacterial properties, evaluation of antibacterial properties and dermal toxicity tests of cotton textile with Zn and Si coating. Antibacterial properties evaluation against pathogenic microorganisms Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli made using the Parallel streak method in accordance with ATCC147 standard. For more specific evaluation of the coated textile, in vitro cytotoxicity test with epidermal HaCat cells was done. It is concluded that the coatings containing Zn and Si obtained by the sol-gel technology can impart antibacterial properties against pathogenic bacteria to the textile by preventing the bacteria from growing; strong inhibition of growth was detected for all test microorganisms. Based on the dermal toxicity test results, it is not expected that the prolonged contact of the skin with coated textiles will have a negative impact on the skin tissue – epidermis.     

Effects of seed roasting temperature and time on the quality characteristics of sesame (Sesamum indicum) oil

The quality characteristics and composition of sesame oils prepared at different roasting temperatures (160–250°C) from sesame seeds using a domestic electric oven were evaluated as compared to an unroasted oil sample: only minor increases (P<0·05) in characteristics, such as peroxide value, carbonyl value, anisidine value and thiobarbituric acid reactive substances, of sesame oils occurred in relation to increasing roasting temperature and time between 160 and 200°C, but colour units of oils increased markedly over a 220°C roasting temperature. Significant decreases (P<0·05) were observed in the amounts of triacylglycerols and phospholipids in the oils prepared using a 250°C roasting temperature. The amounts of γ-tocopherol and sesamin still remained over 80 and 90%, respectively, of the original levels after roasting at 250°C. In the oil prepared using a 250°C roasting temperature, sesamol was detected at 3370 mg per kg oil, but sesamolin was almost depleted after 25 min of roasting. Burning and bitter tastes were found in the oils prepared at roasting temperatures over 220°C. The results suggested that a high-quality product would be obtained by roasting for 25 min at 160 or 180°C, 15 min at 200°C and 5 min at 220°C when compared with the other samples. © 1997 SCI.     

茉莉香精微胶囊的制备及其芳香织物的耐久性能研究

采用原位聚合法制备了茉莉香精微胶囊,对棉织物进行了芳香整理并深入研究了其耐久性能。结果表明：红外光谱（FTIR）和光学显微镜（0M）分析显示成功制备了茉莉香精微胶囊,其平均粒径约为2．6μm且具有较好的热稳定性能。运用浸轧一焙烘工艺对棉织物进行芳香整理研究发现聚氨酯粘合剂处理的芳香织物最高可以耐5次水洗,聚丙烯酸粘合剂处理的芳香织物最高可以耐15次水洗且提升焙烘条件有利于提高其耐水洗性能,聚氨酯粘合剂的最佳焙烘工艺为150℃下处理2min,聚丙烯酸粘合剂的最佳焙烘工艺为160℃下处理2min,整理后织物的断裂强力和硬挺度有一定的提高,游离甲醛含量达到内衣释放标准。     

Hydrophobic sol–gel‐based coating agent for textiles: improvement by solvothermal treatment

This paper reports on the preparation and solvothermal treatment of a hydrophobically modified sol–gel coating agent used in textile applications. The solvothermal treatment is performed in an autoclave vessel up to process temperatures of 180°C and working pressures of 18 bar. The application of solvothermally treated coating agents onto textile fabrics lead to the same water‐repellent properties as the analogous coating agent prepared at room temperature. However, the wash fastness of such water‐repellent coatings can be significantly enhanced if the coating agent is solvothermally treated at intermediate process temperatures of 120–140°C. Especially advantageous is the combination with a plasma pre‐treatment of the textile fabric before application of the sol–gel coating agent. With the background of these experiments, it could be stated that the solvothermal treatment of coating agents for textile refinement is in general an interesting method to improve already developed coating agents.     

Low-surface-energy materials based on polybenzoxazines for surface modification of textiles

The benzoxazine monomers, 3-tert-butyl-3,4-dihydro-8-allyl-2H-1,3-benzoxazine (Benz-m) and 2,2-bis(3-methyl-3,4-dihydro-2H-1,3-benzoxazinyl) propane (Benz-b) were synthesized successfully using Mannich reaction. The formation of the monomer was confirmed by ¹H NMR and FTIR spectroscopy. Both the monomers were coated onto cotton fabric and the fabric samples were then dried at 60°C and cured at 120°C for varying time period. During the curing process, monomer was converted to polybenzoxazine by ring-opening polymerization of oxazine ring. In the Raman spectra, presence of the characteristic absorption bands due to benzoxazine structure at 952, at 1037 and at 1348?cm^?1 even after curing at 120°C for 2?h, suggested incomplete ring opening of benzoxazine to form polybenzoxazine. Also, the lack of durability of the finish to washing appears be due to the mild conditions of curing. Therefore, the application of Benz-b monomer was investigated on polyester (PET) fabric, which could be subjected to higher temperature however for shorter duration. The water and oil (ethylene glycol) repellency was measured to determine the hydrophobicity and oleophobicity of the finish on PET fabric. It was found that there was a marked improvement in the durability to laundry when compared with the treated cotton samples. This study provides a unique and easy method to prepare a low-surface-energy material through a simple thermal treatment procedure without using fluoro polymers or silicones.     

水性聚氨酯的合成及其在棉织物表面的应用

 采用聚碳酸酯二醇(PCDL)、二羟甲基丙酸(DMPA)、异佛尔酮二异氰酸酯(IPDI)为预聚原料,三羟甲基丙烷(TMP)为扩链剂合成具有交联结构的水性聚氨酯多元醇分散体,与多异氰酸酯固化剂组成双组份水性聚氨酯涂层,并将其应用于纯棉织物表面以研究涂层对棉织物耐水性能的影响,实验对涂层织物进行了扫描电镜(SEM)、表面接触角和吸水率测试。结果表明,经过处理的织物表面纤维束都被涂层粘附在一起,表面具有很好的疏水性,对水的接触角可以达到130°,而且织物吸水率降低至9%,另外经过处理的织物还具有很好的耐水洗性,在反复经过水洗12次后,其接触角仍能达到90°以上,吸水率比处理前也要小得多。     

Synthesis and Application of Reactive Carbohydrates. Part VI: Application of Reactive Carbohydrates Derived from Starch and Hydrolyzed Starches to Cotton Fabric

Native starch, 15 min, 30 min, 45 min and 60 min hydrolyzed starches were converted to reactive carbohydrates via graft polymerization with acrylamide followed by methylolation with formaldehyde. The reactive carbohydrates so obtained were applied to cotton fabric according to the conventional pad-dry-cure method under different conditions. The latter included the catalytic system and the curing conditions. The pad-cure and the pad-batch methods were also applicated. Examination of the treated fabrics for nitrogen content as a measure of the extent of reaction, occuring between the methylol groups of the reactive carbohydrate and the hydroxyl groups of cotton cellulose, as well as durability of the finish on the fabric indicated the dependance of the reaction and durability on nature of both reactive carbohydrate and catalyst as well as curing conditions. Reactive carbohydrate derived from 15 min hydrolyzed starch along with mixed catalyst, namely MgCl₂ · 6 H₂O/citric acid (20:80), constitute the most appropriate finish/catalyst combination provided that application is carried out according to the pad-dry-cure method; drying is effected at 100°C for 2.5 min while curing is expedited at 130°C for 30 s.     

棉织物纳米TiO_2抗紫外线整理

针对纺织品整理时直接使用纳米粒子存在易团聚、分散较困难的问题,采用溶胶凝胶法制备纳米TiO2溶胶,再将其制成织物整理剂。用整理剂对棉织物进行整理(浸轧法),用XRD、扫描电镜(SEM)和X射线能谱仪对制得的TiO2及整理前后的织物进行表征,并测试整理后织物的抗紫外线性能及其他服用性能。结果表明:制得的TiO2为锐钛矿晶型;整理后的棉织物具有优异的抗UV性能;UPF值达到50+级别。标准水洗(皂洗)实验结果显示,50次洗涤后织物的UPF值稍有下降,但仍可保持在50+水平。整理后棉织物的断裂强力没有下降,透气性基本不受影响。     

Ultrasonication and Fresh Produce (Cos lettuce) Preservation

Washing Cos lettuce in various sanitizers at different concentrations with and without ultrasonication (40 KHz) reduced the microbiological counts by 1 to 2.5 log colony‐forming units (CFU)/g immediately after washing. Ultrasonication of Cos lettuce in water, chlorinated water, peracetic acid, hydrogen peroxide, and their combinations at various temperatures (4 °C, 20 °C, 35 °C, 47 °C, and 50 °C) had no significant effects (P > 0.05) on the total or the psychrophilic counts during storage at 10 °C. The total count in Cos lettuce reached 9.74 ± 0.035 log CFU/g after ultrasonication (2 min at 50 °C) in chlorinated water (100 mg/L) and storage for 6 d at 10 °C. Extending the ultrasonication (40 kHz) of Cos lettuce for up to 20 min did not improve the bactericidal effect of ultrasonication. However, long‐time ultrasonication (20 min) caused significant (P < 0.05) damage to the quality of Cos lettuce tissues.     

Chitosan phosphate: A new way for production of eco-friendly flame-retardant cotton textiles

An increase in the health and environment legislation awareness pushed the textile manufacturers to develop their strategies to produce eco-friendly flame-retardant textiles with competitive cost. Chitosan is added during the phosphorylation process as a nitrogen source that has synergistic effect with phosphorus. Increasing the chitosan concentration from 0% to 2% enhances the flame retardancy of the treated cotton fabric against successive washing. Further increase in amount of chitosan, above 2%, has a limited effect on the thermal degradation of the treated cotton. Increasing diammonium hydrogen phosphate (DAHP) concentration from 0% to 10% is responsible for making the flame-retardant finish durable against successive washing. Thermal degradation analysis of treated fabrics at different DAHP concentrations shows a decrease in the maximum degradation rate point and thermal degradation onset point. The amount of residue at 500°C increases till reaches 32% with the increase in the DAHP concentration. The effect of curing temperature and time has been discussed in detail. The performance properties of the treated cotton fabrics show better physical and chemical properties than that in the absence of chitosan.     

Wrinkle-free finishing of cotton fabrics based on click chemistry via ultraviolet radiation

In this paper, a novel method was proposed to achieve anti-wrinkle finishing of cotton fabrics. Cotton fabrics were pre-treated to terminate –OH groups and reduce the amount of –OH groups by the reaction between the –OC₂H₅ groups of 3-mercaptopropyltriethoxysilane and –OH groups of cotton fabrics. Then anti-wrinkle finishing of cotton fabric was obtained with waterborne polyurethane acrylate under ultraviolet radiation (UV) where click reaction between –SH groups and C=C bonds was taken place. The surface morphology, reaction and mechanical properties of cotton fabrics were investigated. The results show that the wrinkle recovery angle (WRA) of cotton fabrics reaches 205°, and the WRA can maintain 190° after 10 washing cycles, revealing that the anti-wrinkle finishing on cotton fabrics has durable effect. Furthermore, the anti-wrinkle finishing cotton fabrics maintain good mechanical properties like breaking strength.     

Microwave Assisted Modulation of Vat Dyeing of Cellulosic Fiber: Improvement in Color Characteristics

The role of radiations in textile processing is gaining attention due to its low cost, energy effectiveness and eco-friendly process. This study is concerned with the improvement in modulation of microwave assisted vat dyeing of cellulosic fiber. It was found that radiation treatment of both cotton fabric and dye solution for 1 min gives good color strength, while for redox reaction, 2.5 g of NaHSO₃, 2 mL of CH₃COOH, and 1.5 mL of H₂O₂ are the optimized conditions which show it is a cost-effective tool. Good color strength was obtained at 65 °C for 1 h dyeing using 50 mL of optimal solution in dye bath at pH 9. Finally, ISO standards for color fastness to light, washing, rubbing and perspiration were applied at 0.5–2.5% of shade at optimal conditions which showed that microwave treatment has enhanced the color characteristics. Hence, the technique can successfully and easily be employed for surface modification of fabric for good quality dyeing with various classes of dyes.     

Hot water and curing treatments reduce chilling injury and maintain post-harvest quality of 'Valencia' oranges

‘Valencia’ oranges [Citrus sinensis (L.) Osbeck] were harvested at optimal maturity and either dipped in hot water at 53 °C for 3 or 6 min or at 48 °C for 12 min or cured at 53 °C for 1 or 6 h or at 48 °C for 12 h. The fruits were not degreened, waxed or treated with any post‐harvest fungicides. All fruit samples were stored at 4 °C for 6 months following the treatments. Both hot water dip and curing treatments reduced chilling injury and decay when compared with the untreated control. The most effective treatments were curing of fruit at 53 °C for 6 h and at 48 °C for 12 h. Weight loss and juice yield were higher in cured fruits than those from other treatments, but the heat treatments had no consistent effects on titratable acid, soluble solids, ascorbic acid and peel colour. It was concluded that a pre‐storage hot water dip and curing at high temperatures might be beneficial in preventing chilling injury and decay of ‘Valencia’ oranges for 6 months of storage at 4 °C.     

Modulation of Marigold Based Lutein Dye and its Dyeing Behaviour Using UV Radiation

Application of natural dyes has increased interest in the past few years due to the eco-friendly behavior of these dyes. The present research is concerned with the effect of UV on dyeing behavior of cotton using marigold as source of natural Lutein dye. This is colorant lutein which imparts greenish yellow color to cotton fabric. The dye powder and cotton fabric were exposed to UV-radiation for different time intervals prior to dyeing and dyeing was performed at different dyeing variables. International Standard Organization (ISO) methods were employed to evaluate the color fastness properties, such as color fastness to light, washing and rubbing. It is found that 90 min exposure of UV radiations was the optimum condition for surface modification and dyeing of 70 min at 40°C give excellent results using 4 g/L salt to achieve maximum exhaustion. For improvement of color fastness, tannic acid (8%) as pre- and 6% as post-mordant is the best condition. It is found that UV ray treatment can be used to other fabrics followed by dyeing using extracts of dye yielding plants without any physical characteristics damage.     

Effect of Washing Treatment on Quality of Minced Mullet Flesh

Washing treatments were evaluated for quality improvement of minced mullet. Thiobarbituric acid (TBA) number generally decreased with increased washing temperature from 5–35°C and increased at higher temperatures. At 35°C, a wash water pH of 6.0 or above resulted in decreased TBA number. Response surface analysis indicated maximum whiteness index, minimum TBA number, and minimum cooking loss with washing at 29–33°C for up to 10 min with a water to flesh ratio from 23–26. Highest springiness was indicated with washing ratio of 25 to 30 at 28–31°C The simultaneously optimized washing conditions for highest minced mullet quality were 31.4°C for 7.5 min at a ratio of 24.     

棉织物溶胶-凝胶法的无氟拒水整理研究

以接触角作为评价依据，研究了纯棉织物经不同改性二氧化硅溶胶处理纯棉织物后的拒水性能。讨论了改性剂结构、浓度、处理物表面粗糙程度及洗涤次数对接触角的影响。试验表明，整理棉织物的拒水性随溶胶中烷基硅烷添加剂浓度和烷基链长度的增加而提高；改性溶胶处理后，织物的拉伸强力减小，而白度和透湿量变化不大。     

基于短链含氟丙烯酸酯细乳液的棉织物拒水拒油整理

针对织物拒水拒油整理过程中出现的环境污染、整理效果不佳以及耐洗牢度差等问题,通过细乳液聚合法合成了四碳短链含氟丙烯酸酯细乳液,考察了其对棉织物的拒水拒油整理效果。以单因素分析法探讨预处理方式、细乳液质量浓度、预烘工艺及焙烘工艺对棉织物的水油接触角的影响,得到等离子体预处理棉织物拒水拒油整理的最佳工艺条件:细乳液质量浓度为60 g/L,浸渍时间为30 min,80 ℃预烘3 min,160 ℃焙烘3 min。在此最佳条件下,棉织物对水、橄榄油和十六烷的接触角分别为160°、154°、135°;经30次洗涤后,棉织物对水、橄榄油和十六烷的接触角分别为145°、133°、113°;整理后棉织物的折皱回复角提高36%,断裂强力及白度均无明显下降。