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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   
132.
133.
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   
134.
李辰  徐斌  张长华 《山西建筑》2012,38(4):146-147
以某纺织污水处理厂为实例,对运行过程中生物接触氧化单元出现的生物膜过厚、生物膜发白和红斑瓢体虫大量爆发的问题进行了解析,并提出了相应的对策和控制措施,不仅解决了实际问题,还可为国内其他污水处理厂提供指导。  相似文献   
135.
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   
136.
以废旧毛涤黏混纺面料为研究对象,首先对面料进行清洁与消毒,然后对其组分进行定性、定量分析,最后通过单因素法优化,得出最佳的溶胀工艺为:m_(废旧面料)∶m_(DMSO)=1∶10,溶胀时间40 min,溶胀温度90℃。在该工艺下对织物进行溶胀处理,得到织物的质量损失率为3.06%,K/S值为16.906。  相似文献   
137.
EPS与棉花秸秆矿渣复合保温材料研究   总被引:1,自引:1,他引:0  
在前期石膏、棉花秸秆纤维矿渣等墙体复合材料研究的基础上,通过掺加EPS颗粒研制出一种轻质、隔热、具有一定强度等多功能新型墙体复合材.该材料以EPS颗粒为保温骨料,矿渣为骨料,水泥、石膏为胶凝材料,通过掺加粉碎的棉花秸秆纤维来解决无机、有机材料界面的粘结强度低及EPS颗粒上浮的问题,从而试制出一种性能良好的墙体材料.  相似文献   
138.
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.
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   
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