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粘胶纤维的研制和新技术 总被引:1,自引:0,他引:1
本文概述了国内外粘胶纤维的研制、新产品、新工艺匆存在的间题,对超微细粘胶纤维的性能、用途和经济效益作了介绍。新溶剂NMMO纤维素纤维的研究和开发比粘胶纤维工艺大为简化,解决了环境污染的难题,提高了纤维物理性能,实现了粘胶法的根本性改革。 相似文献
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阻燃剂及材料的阻燃处理 总被引:3,自引:0,他引:3
阻燃剂是能够保护材料不着火或使火焰难以蔓延的化学物质。介绍了常见阻燃剂的种类、阻燃机理、材料的阻燃处理及新型阻燃剂的发展,以增强人们对阻燃技术领域的认识和了解。 相似文献
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由于水滑石具有层板阳离子可调控、层间阴离子可交换、酸碱性等独特的性能,在医药、离子交换、催化、材料阻燃等领域备受研究者关注。特别是水滑石用作阻燃材料时,具有无卤、无毒、不产生有毒和腐蚀性气体、阻燃和抑烟性能优良等突出优点,已成为当前材料阻燃领域研究的热点。然而,水滑石也存在热稳定性较差、容易聚集、分散性较差等缺点,故国内外学者开展了一些水滑石阻燃剂改性的系列研究。本文阐述了近年来国内外学者利用Ca2+、Mg2+、Al3+等阳离子对水滑石阻燃剂进行改性,以及应用BO33-、SiO32-等阴离子对水滑石阻燃剂进行改性等方面的研究进展,并对水滑石在生物质材料阻燃、低成本水滑石阻燃剂的合成、水滑石协效阻燃剂的研究、水滑石阻燃剂工业化生产新工艺与设备、洁净化制备技术等方面的研究与应用前景进行了展望。 相似文献
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绿色环保型氢氧化镁阻燃剂 总被引:3,自引:0,他引:3
介绍了阻燃剂的种类和发展趋势,并重点介绍了氢氧化镁阻燃剂的阻燃机理、特点、应用和发展。指出氢氧化镁阻燃剂是一种新型的、对环境友好的无机阻燃剂。 相似文献
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Jianjun ZhangQuan Ji Xiuhong ShenYanzhi Xia Liwen TanQingshan Kong 《Polymer Degradation and Stability》2011,96(5):936-942
Intrinsically flame-retardant calcium alginate fibre was prepared by wet spinning and its pyrolysis products and thermal degradation mechanism studied. Combustion behaviour and flammability were assessed using the limiting oxygen index (LOI) and cone calorimetry. LOI results showed that calcium alginate fibre was intrinsically flame retardant with LOI value of 48.0, as compared to about 20.0 for viscose fibre. Cone calorimetry indicated that heat release rate and total heat release values of intrinsically flame-retardant fibre were significantly less than those of viscose fibre. It also shown that intrinsically flame-retardant fibre combustion produced greater quantities of residues than did viscose fibre combustion. Combustion residues were examined using scanning electron microscopy, indicating that calcium alginate fibre produced consistent, thick residue crusts. Pyrolysis was investigated using pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) which showed that cracking products produced from calcium alginate fibres combustion were less than those in viscose fibre combustion, and pyrolysis of the intrinsically flame-retardant fibre was incomplete. Thermogravimetric analysis (TG) indicated that calcium alginate fibre generated more residues containing carbonaceous char and calcium carbonate, as compared with viscose fibre. We propose a condensed phase mechanism for the calcium alginate fibre flame-retardancy effect. 相似文献
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An oxidative chemical vapor deposition (OCVD) process was used to coat flexible textile fiber (viscose) with highly conductive polymer, poly (3,4‐ethylenedioxythiophene) (PEDOT) in presence of ferric (III) chloride (FeCl3) oxidant. OCVD is a solvent free process used to get uniform, thin, and highly conductive polymer layer on different substrates. In this paper, PEDOT coated viscose fibers, prepared under specific conditions, exhibited high conductivity 14.2 S/cm. The effects of polymerization conditions, such as polymerization time, oxidant concentration, dipping time of viscose fiber in oxidant solution, and drying time of oxidant treated viscose fiber, were carefully investigated. Scanning electron microscopy (SEM) and FT‐IR analysis revealed that polymerization of PEDOT on surface of viscose fiber has been taken place and structural analysis showed strong interactions between PEDOT and viscose fiber. Thermogravimetric analysis (TGA) was employed to investigate the amount of PEDOT in PEDOT coated viscose fiber and interaction of PEDOT with viscose fiber. The effect of PEDOT coating on the mechanical properties of the viscose fiber was evaluated by tensile strength testing of the coated fibers. The obtained PEDOT coated viscose fiber having high conductivity, could be used in smart clothing for medical and military applications, heat generation, and solar cell demonstrators. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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In this research, enzymatic treatment as an environmental friendly process has been used for recycling process of old cellulosic
wastes such as cotton, viscose, and lyocell. Cellulase hydrolyses cellulosic chains and shortens cellulosic fibers. This study
investigates to detect the optimum enzyme concentration and time of treatments for suitable changes of length and weight loss.
The main purposes of this article are shortening of cellulosic fibers and evaluating of enzymatic treatment in different kind
of cellulosic fibers. According to the data of experiments, with the increase of enzyme concentration and the treatment time,
the length and weight loss percentage of the cellulosic fibers has been decreased. The length and weight loss percentage of
treated viscose is more than that of lyocell and cotton fibers. Optimized condition, reaction time, and enzyme concentration
have been determined by mean length of treated cellulosic samples. Suitable longitudinal distribution of fiber for papermaking
industries is in the range of 0 to 4 mm. Optimum enzyme concentration and treatment time for recycling cotton, lyocell, and
viscose fibers are 2% and 48 h for cotton and lyocell and 0.5% and 48 h for viscose, respectively. According to the data of
experiment, the length of treated fibers is appropriate for its usage as a raw material in papermaking industries. 相似文献
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Comparative investigations of new regenerated cellulosic fibers, bamboo viscose fiber and Tencel, together with conventional
viscose fibers have been carried out to explain the similarity and difference in their molecular and fine structure. The analyses
jointly using SEM, XRD and IR reveal that all the three fibers belong to cellulose II. Tencel consists of longer molecules
and has a greater degree of crystallinity, while bamboo viscose fiber has a lower degree of crystallinty. TG-DTG-DSC study
shows three fibers resemble in thermal behavior with a two-step decomposition mode. The first step is associated to water
desorption, suggesting that bamboo viscose fiber holds better water retention and release ability, the second a depolymerization
and decomposition of regenerated cellulose, indicating that Tencel is more thermally stable in this process than bamboo and
conventional viscose fiber. 相似文献
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Cellulose, the most abundant renewable organic material on earth, exhibits outstanding properties and useful applications, but also presents a tremendous challenge with regard to economical and environmentally friendly chemical processing. The viscose process, more than 100 year old is still the most widely utilized technology to manufacture regenerated cellulose fibers and films. Viscose fibers are produced today worldwide on a 5 million ton scale with various fiber types ranging from high performance tire yarn to textile filaments and staple fibers with excellent properties close to those of cotton. At Fraunhofer IAP, the technical equipment for viscose preparation, wet spinning of fibers, hollow fibers, and tube-like films is available on a min-plant scale. Research focused on raw materials testing, process optimization with regard to economic and ecological aspects, structural analysis of cellulose during processing, and structure–property relations of fibers and films. Similar to the viscose process, cellulosic fibers can be produced via cellulose carbamate as an environmentally friendly route. In a close cooperation of Fraunhofer IAP with industrial partners, a specific process based on cellulose carbamate was developed on a pilot plant scale, giving fiber properties close to those of conventional viscose fibers. In recent decades the N-methylmorpholine-N-oxide (NMMO)-technology turned out to be a nonderivatizing commercial alternative to the still dominant viscose route. From the very beginning, Fraunhofer IAP has been engaged in investigating the structure formation of cellulose fibers precipitated from NMMO-water solution, revealing structural reasons for the fibrillation tendency of these fibers and means to overcome them. Starting from fiber formation via dry-jet wet spinning, for the first time the blown film formation and the meltblown nonwovens technology were developed for cellulosics on a pilot plant scale at Fraunhofer IAP. Based on the elastic behavior of the dope at elevated temperatures, cellulose can be processed like a melt in the air-gap, offering new possibilities of shaping cellulose like meltable mass polymers. Combining cellulose carbamate with NMMO-monohydrate as a solvent, higher polymer concentrations in the dope and outstanding mechanical properties of the resulting fibers were achieved. 相似文献
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J. J. Suñol J. Saurina F. Carrasco X. Colom F. Carrillo 《Journal of Thermal Analysis and Calorimetry》2007,87(1):41-44
Lyocell, modal and
viscose fibers were subjected to mercerization or to solar degradation. The
ulterior thermal degradation was analyzed by means of differential scanning
calorimetry (DSC). Thermal analysis shows wide exothermic processes that began
between 250 and 300°C corresponding to the main thermal degradation and
are associated to a depolymerization and decomposition of the regenerated
cellulose. Thermal degradation was analyzed as a function of concentration
and time. Lyocell fiber is the most stable under thermal degradation conditions.
Furthermore, mercerized samples are initially more degraded and present a
lower thermal stability. 相似文献
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《Journal of Polymer Science.Polymer Physics》2018,56(12):947-957
In this work, sorption and dielectric properties of viscose/polypropylene multipurpose nonwoven fabrics were examined. The analysis of sorption behavior showed that the changes of the water absorptive capacity, the height of capillary rise and water retention value are in a function of viscose fiber content, total porosity, the pore size and used web bonding process. It is observed that dielectric properties at frequencies from 30 Hz to 140 kHz, for samples exposed to different relative air humidity and wet samples, are dependent on viscose fiber content, web bonding process, frequency of electric field and bulk free water content. The effective dielectric permeability of wet samples rapidly decreases with an increase in frequency up to 3 kHz while spectra of the AC specific electrical conductivity showed a plateau above 13 kHz. It is also observed that the dielectric properties of wet samples increase by several orders of magnitude compared to dry samples. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018 , 56, 947–957 相似文献
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The splitting tendency of viscose and modal fibers in aqueous alkali solutions of LiOH, NaOH, KOH and TMAH was investigated.
The viscose fibers splitted up to 5–7 fibrils, whereas modal fibers splitted up to 2–4 fibrils depending on alkali type and
concentration. The fibrillar structure of lyocell enables it to split more (15–20 fibrils) than viscose and modal fibers.
Splitting occurs where internal stress of fiber is high due to different alkali or void distribution inside fiber. The splitting
test couldn’t be achieved for viscose and modal fibers between 1 and 5 M concentration of NaOH and TMAH solutions due to breakage
of fibers during test. Above 5 M concentration, no split can be observed due to even distribution of alkali inside fiber.
Paper presented at the 7th World Textile Conference, AUTEX 2007, Tampere, Finland, 26–28 June 2007.
Christian-Doppler Laboratory of Textile and Fiber Chemistry of Cellulosics is a Member of European Polysaccharide Network
of Excellence (EPNOE), www.epnoe.org 相似文献
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In this study, a new xylan enriched viscose fiber was developed. A high molecular weight xylan with a degree of polymerization of 150–200 was added during a late stage of the viscose production process. The xylan deriving from a cold caustic extraction (CCE) of an eucalypt paper pulp was introduced to the process after xanthation and thus neither objected to any degradation conditions during alkalization nor to the xanthation step. About 90 % of the added xylan was transferred to the final fiber. A xylan content of up to 7.5 % was achieved. Fiber properties like strength showed a comparable level to the reference fibers while the water retention value was clearly raised due to the higher content of hemicelluloses. The hemicellulose distribution over the fiber cross section was investigated by enzymatic peeling. Even though a segregation of the different polysaccharides was observed, the goal of a good blending of CCE-xylan into cellulosic fibers with new interesting features was achieved. 相似文献
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Electron treatment of wood pulp for the viscose process 总被引:3,自引:0,他引:3
Electron processing is currently being evaluated by several viscose producers for integration into their process. The viscose industry converts dissolving wood pulp into products such as staple fibre, filament, cord, film, packaging, and non-edible sausage casings. These materials are used in the clothing, drapery, hygiene, automobile, food, and packaging industries. Viscose producers are facing increasingly high production costs and stringent environmental regulations that have forced some plants to close. Electron treatment of wood pulp can significantly reduce the amounts of chemicals used for producing viscose and the production of hazardous pollutants. Acsion Industries has worked with companies worldwide to demonstrate the benefits of using electron treated pulp for producing viscose (rayon). This paper describes the viscose process, the benefits of using electron treatment in the viscose process, and Acsion’s efforts in developing this technology. 相似文献