A mathematical model for simulating heat and moisture transfer within porous cotton fabric drying inside the domestic air-vented drum dryer

A mathematical model was developed to describe the processes of coupled heat and mass and momentum transfer occurring in convective drying of 100% porous cotton fabric. In this model, the variation in both air and fabric properties were expressed as a function of temperature and moisture content. The resulting systems of transient non-linear partial differential equations in the space-time domain together with the set of initial values and boundary conditions were numerically solved by utilizing the finite difference method. A series of laboratory drying experiments were performed using a computer-controlled dehydration system, which was developed to obtain data of drying kinetics under varying operating conditions for the validation of the predicted results from the proposed model. The experimental results has shown a very good agreement with the predictions of the model, which indicates that the proposed numerical model can be used with confidence as a tool in optimizing the design and operation of the fabric drying system. A parametric study was performed using the modeling tool has demonstrated the impact of key operational parameters on the drying kinetics, which has significant meaning on improving fabric’s appearance smoothness and decreasing the damage. It is expected that the model can be applied for other fiber products and processes involving similar phenomena.     

Synthesis of reactive waterborne polyurethane modified with quaternary ammonium chain extender and its color fixation properties

N-Methyl diethanolamine was adopted to react with isophorone diisocyanate to provide a dihydroxyl complex. The obtained complex was further modified by benzyl chloride through alkylation reaction to offer a cationic quaternary ammonium chain extender. Polyether glycol was selected as the soft segment to prepare the waterborne polyurethane (WPU) prepolymer. Then, as-prepared cationic chain extender was blocked into the achieved WPU prepolymer, and the residual NCO groups were tentatively terminated by NaHSO₃ at a low temperature to obtain WPU emulsion. The structure of WPU was confirmed by Fourier Transform Infrared spectrometry, Gel permeation chromatography, Thermogravimetric analysis, and scanning electron microscopy. The color fastness of dyed cotton fabrics was obviously promoted after treating by WPU latex, and the wet rubbing fastness of cotton fabrics obviously improved 1.5 grade.     

Structural and Chemical Characteristics of Sisal Fiber and Its Components: Effect of Washing and Grinding

This work covers the study of microstructural changes of natural sisal fibers induced by different conditioning pre-treatments: mechanical grinding, cryogenic grinding, and hot water washing. The aim of the work is to clarify the effects of the pre-treatments on crystallinity and infrared spectra of sisal. Scanning electron microscopy results allowed to identify morphological changes on the fiber surface. Deeper changes of chemical origin were studied by attenuated total reflectance/Fourier transform infrared spectroscopy (FTIR) and focused on the main components of cellular walls: cellulose, lignin, and xylan. The work was complemented with crystallinity index (I_c) data determined by two very different methods: the widely used for lignocellulosic fibers Segal equation based on X-ray diffraction measurements, and the other based on FTIR through the 1430/900 cm^?1 band intensity ratio, which is mostly used with cellulosic samples.     

白坯仿牛仔面料的纺织工艺和产品开发

文章介绍了一种采用不同性质的双根粗纱生产涤棉竹节纱的方法,并利用生产的竹节纱织造白坯布,在染色时根据涤纶和棉纤维的染色不同性,染棉不染涤。最终获得仿牛仔风格的面料,而且缩短了工艺流程,降低了生产成本。     

竹节纱粗细节形成机制及其纺纱工艺比较

为探究不同竹节纱生产装置的品种适应性,开发竹节纱新品种,根据纺制竹节纱时喂入粗纱根数、牵伸机构组成、罗拉变速方式、牵伸比调控方式的不同,将现有竹节纱生产装置分为单通道后罗拉喂入竹节纱装置、单通道中后罗拉喂入竹节纱装置、双通道中后罗拉喂入竹节纱装置、双通道后罗拉喂入竹节纱装置、三通道后罗拉喂入竹节纱装置共5种装置,系统分析了不同竹节纱生产装置形成粗细节的机制,构建了竹节纱可变线密度的计算公式。以调控线密度和混纺比变化为目标对5种装置纺制竹节纱的工艺特点进行了分析比较。利用三通道后罗拉喂入竹节纱装置纺制了粗细和混纺比均变化的彩色竹节纱。     

皂洗酶复配及其在染色后处理中的应用

应用漆酶DeniliteⅡS进行了染液脱色与棉染物酶洗试验,考察了不同助剂对漆酶处理效果的影响。结果表明：阴离子表面活性剂十二烷基硫酸钠、螯合剂EDTA等对漆酶酶活有一定的抑制作用;非离子表面活性剂平平加O和吐温-80能增加漆酶反应活性,使脱色率（数量、比例）增加。漆酶与吐温-80复配的皂洗酶对棉染物有较好的酶洗效果,处理后织物湿摩擦牢度有所增加。     

棉织物的丝胶涂层整理及其性能

为开发高品质、功能性的棉制品,采用带负电荷的丝胶蛋白与带正电荷的壳聚糖衍生物在水溶液中发生反应,生成具有一定胶黏作用的新型微颗粒,再通过聚丙烯酸类低温交链剂进一步将丝胶固着在棉织物上。对整理前后棉织物的服用性能、表面形态等进行测试,结果表明:丝胶均匀涂覆在棉织物上,且耐洗性良好,洗涤5次后的溶失率约为0.21%,丝胶整理后棉织物的吸放湿性、保温性、透湿性和抗菌性均有提高,透气性基本不变,是一种新型高档棉制品。     

棉纺异物检测清除机的现状分析

阐明了清除异物的重要性和异物检测清除机的作用。介绍了国内外异物清除机主要机型、技术特征以及基本结构和原理。提出了对异物清除机的基本要求，并就它的安装位置、检测传感器的配置、检测分辨率、检出率和除杂率与生产产品关系进行了浅析和研讨。     

FA326型并条机的使用实践

为了满足市场需求,提高成纱质量水平,我公司购置了8台FA326型并条机,其目的在于改善条干水平,提高半制品质量,增加产品的市场竞争力。文章叙述了使用FA326型并条机过程中的体会与建议。     

精并粗工艺与成纱品质(二)

根据弯钩纤维牵伸理论,对并条和精梳准备工艺进行了定量分析,提出了新观点及应用实例,并对罗拉牵伸的一般规律进行了定性分析.对近年出现的电脑粗纱机的使用提出了注意事项.