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131.
Blend fabrics of cotton and polyester are widely used in apparel, but high flammability becomes a major obstacle for applications of those fabrics in fire protective clothing. The objective of this research was to investigate the flame retardant finishing of a 50/50 polyester/cotton blend fabric. It was discovered previously that N,N′‐dimethyloldihydroxyethyleneurea (DMDHEU) was able to bond a hydroxy‐functional organophosphorus oligomer (HFPO) onto 50/50 nylon/cotton blend fabrics. In this research, the HFPO/DMDHEU system was applied to a 50/50 polyester/cotton twill fabric. The polyester/cotton fabric treated with 36% HFPO and 10% DMDHEU achieved char length of 165 mm after 20 laundering cycles. The laundering durability of the treated fabric was attributed to the formation of polymeric cross‐linked networks. The HFPO/DMDHEU system significantly reduced peak heat release rate (PHRR) of cotton on the treated polyester/cotton blend fabric, but its effects on polyester were marginal. HFPO/DMDHEU reduced PHRR of both nylon and cotton on the treated nylon/cotton fabric. It was also discovered that the nitrogen of DMDHEU was synergistic to enhance the flame retardant performance of HFPO on the polyester/cotton fabric. 相似文献
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Polypyrrole (PPy) is one of the preferred alternatives among the intrinsically conductive polymers (ICPs). In this study, PPy-coated cotton (PPy-CT) fabrics were synthesized by two step in situ chemical polymerization. The reaction parameters, such as monomer concentration and temperature, were studied in detail. The surface resistivity of PPy-CT fabrics ranged ∼ 15–5000 Ω−2. To assess long-term usage potential, the atmospheric aging of conductivity characteristics of treated fabrics was monitored over a period of 6 months. It was found that the synthesis temperature had a significant impact on conductivity and atmospheric aging of PPy-CT fabrics. Furthermore, various sulfonic acid sodium salts added as external doping agents during polymerization also had a positive effect. The scanning electron microscopy revealed smoother morphology of sulfonic acid salt doped PPy coatings. The overall study addresses the durability aspect of PPy-CT fabrics in potential applications areas. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
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M.Geubtner G.Lang J.P.Moldenhauer S.Schneider-Müller H.Wünsche R.Zyschka 李梦雅 程心怡 《国际纺织导报》2016,(10):56-57
基于更为严厉的甲醛重新分类的背景,TEGEWA协会整理工作组已开发出一种可确定纺织助剂中游离甲醛含量的新方法。目前此法鉴于其统一的程序,可使因不同的内部测试方法而得出不同观点的测试成为过去。 相似文献
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Cellulose furoate was synthesized via heterogeneous and homogeneous reactions. Cotton cellulose and wood cellulose were used. Lithium chloride/dimethylacetamide solvent was used to dissolve the cellulose for the homogeneous reaction. The esterification reaction between cellulose and 2‐furoyl chloride was systematically studied. It revealed that the activation of cellulose was important for its esterification reaction. Activation by solvent exchange decreased the crystallinity and increased the accessibility of cellulose. X‐ray diffraction analysis showed no significant change in the spectrogram after activation of cellulose. The degree of substitution of cellulose furoate was influenced by the molecular weight of the cellulose, the stoichiometry of the reagents, the acid scavenger, and the reaction time. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2649–2655, 2001 相似文献
139.
Cotton fibers treated with liquid ammonia and sodium hydroxide were hydrolyzed with crude cellulase. The structural change in the fibers due to the cellulase treatment was examined in relation to the apparent affinity of Congo Red. The cellulose III crystalline structure collapsed and generated intermediate‐molecular‐ordered regions on cellulase treatment. Adsorption of Congo Red occurred on the crystallite surfaces of cellulose II and cellulose III that was transformed from cellulose II. The fiber, the dominant crystallite phase of which was cellulose III that was transformed from cellulose II, had a considerably increased apparent affinity after cellulase treatment. The intermediate structure on the crystallite surface was associated with the adsorption of Congo Red in the cases of cellulose II and cellulose III. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 1675–1680, 2001 相似文献
140.
Abhinesh Kumar Prajapati Neha Sharma Rakesh Kumar Jena Preena Shrimal Parth Bagtharia Rajesh Kumar Kaushal 《分离科学与技术》2016,51(13):2276-2283
The electrochemical treatment (ECT) of textile wastewater was carried out in a 1.5 dm3 electrolyte batch reactor using iron electrodes. With the four plate configurations, a current density (CD) of 89.2 A/m2 and a pH value of 8.5 were found to be optimal, at which maximum reduction in chemical oxygen demand (COD) and colour achieved were 86% and 79%, respectively. Loss of 0.0666 kg/m3 iron electrode and 18.44 kWh/m3 power consumption was observed during ECT with a maximum COD reduction of 79%. The settling characteristics of electrochemically treated effluents as well as the characteristics of foam and residue were also analysed. 相似文献