腈纶纤维特性用途及生产工艺研究

腈纶工业开始于20世纪50年代，它的发展经历了快速时期，也经历了发展的缓慢时期，在21世纪的今天，腈纶工业的发展速度呈现出了螺旋上升的趋势，在发展中国家占有一席之地，在发达国家之中产量在逐渐减少。腈纶有很多种用途，而且腈纶的产量非常大，价格也很便宜，质量也不比羊毛和棉花的质量差，是一种既实惠又高质的纺织材料，在纺织行业中有着非常重要的地位。当然腈纶的生产工艺也是多种多样的。本文就对腈纶纤维的特性用途及其的生产工艺进行研究。     

浅析我国腈纶工业的现状及发展方向

简要介绍了我国腈纶工业的现状，并在此基础上，根据我国国情，对我国腈纶发展步伐和策略，提出了意见和建议。指出腈纶应扩大原料生产，加快设备的国产化。     

我国腈纶工业的发展前景

阐述了腈纶的特点及世界腈纶发展趋势 ,并对我国腈纶纺织品出口等方面进行了分析 ,提出了今后我国腈纶工业应加强技术创新 ,利用加入 WTO的机遇 ,适时适量发展腈纶工业。     

我国腈纶工业现状及发展策略之我见

概述了40年来中国腈纶工业的发展过程,分析了腈纶工业的现状和存在的问题,阐明了我国腈纶工业今后的发展策略,认为生产规模化、设备国产化及加强差别化纤维和功能性纤维的研究开发是中国腈纶工业的根本出路。     

世界腈纶工业发展趋势及对我国的启示

世界各地区的腈纶工业呈现不同的发展趋势,欧美发达地区的一些大腈纶生产厂家淡出腈纶业,而日本腈纶业仍以产品开发求胜。根据我国腈纶工业的现状,借鉴发达地区的发展战略,探讨了我国腈纶业发展的出路。     

对阻燃腈纶的几点探讨

本文以对阻燃腈纶的制造方法作了介绍，论述了国内阻燃腈纶科研生产的历史现状，对发展我国化工业谈了自己的看法。     

发展我国腈纶柔性生产体系的设想

回顾了腈纶的发展历史,分析了国内腈纶工业发展的现状以及在增加产量的同时应重视品种开发。对如何发展我国腈纶柔性生产体系提出了有实际意义的设想,为腈纶老企业技术改造和产品开发提供参考。     

我国腈纶工业的发展

分析了我国腈纶工业的现状及发展。我国腈纶需求旺盛,经济效益低下阻碍了腈纶的发展。指出应提高原料丙烯腈的自给率,开发以丙烷为原料替代丙烯生产丙烯腈的工艺;降低腈纶生产第二单体和溶剂的生产成本,建议采用醋酸二甲胺法生产二甲基乙酰胺(DMAc),DMAc二步法生产差别化腈纶来提高腈纶差别化率;实施腈纶上下游垂直整合,以促进我国腈纶工业的和谐发展。     

世界腈纶及丙烯腈发展预测

对世界腈纶及其原料丙烯腈的现状及今后发展趋向作了简要回顾与分析，并预测了２０００年世界腈纶及丙烯腈的发展数量及供需平衡关系。     

我国腈纶工业现状及发展前景

分析了我国腈纶工业现状,展望了腈纶工业的发展前景。我国腈纶生产能力和消费量有较大差距,自给率只有60%左右,腈纶工业尚有发展空间,指出这一空间将主要由新建项目来填补。我国腈纶工业生产主要是NaSCN法、DMF法和DMAc法3种工艺路线并存,而DMAc工艺路线具有较大的优势,新建项目应优先考虑采用DMAc二步法湿纺路线。今后我国腈纶工业的发展将呈现国资、民资、外资或中外合资共存的局面。     

我国特种PAN纤维的开发现状及发展前景

本文从碳纤维、预氧化纤维和离子交换纤维叙述了特种PAN纤维的用途和世界需求量,以及我国目前特种PAN纤维的开发现状以及发展前景。我国的碳纤维、预氧化纤维和离子交换纤维等都还处于研制、开发阶段,但已取得了一定的成效。向材料化和功能化发展是合成纤维今后发展的方向,从其实用性和经济效益来看,特种PAN纤维是有发展前途的。     

PAN原丝生产过程对碳纤维强度的影响因素

探讨了碳纤维用PAN原丝生产过程中几个较重要影响因素（聚合物分子量、聚合组分、凝固成型、拉伸、杂质等）对最终碳纤维强度的影响。表明提高碳纤维强度,应该多从原丝生产过程看手采取强化措施。     

我国的化纤工业

回顾了我国化纤工业自1957年以来的发展状况,展望了今后十年的发展趋势。指出为实理2000年化纤产量达2.5—3Mt的目标,必须新建1.5—2Mt的化纤原料装置。作者还进一步论述了各大类纤维的用途、生产原料及市场需求,指出到2000年我国粘纤与合纤之比以1:9为宜,涤纶长丝的比例以35—40%为宜,腈纶在合纤中的比例应挺高到20%左右,锦纶在合纤中所占比重拟扩大到10%。此外,还要大力开发差别亿纤维及高技术纤维。     

Development of high-efficiency chemisorption filters for water treatment. Part 1

The effect of oxidized PAN fibre on the kinetics of synthesis and hardening of the polymer matrix was investigated. it was shown that synthesis and polymer matrix formation in the structure and on the surface of oxidized PAN fibre take place with a higher initial rate. The effect of fibre fillers on the structure of the ion-exchange matrix was investigated. The possibility of direct regulation of the structural characteristics of the ion-exchange matrix was demonstrated. It was shown that the chemisorbents developed can be used in treatment of waste water to remove heavy metal cations. Oxidized PAN fibre is a promising fibre filler in production of Polikon composite chemisorption fibre materials for treatment of wastewaters.     

用图象分析技术测PAN纤维的直径及分布

采用图象分析技术来测定PAN原丝的直径及直径分布,通过计算机软件来进行图象的处理和计算,可提高测量精度,减少人为因素;因测量及数据处理速度快,可大大增加统计的样本量,使测量值更接近于真值,统计的结果可靠。本实验测定了国内(J_3k)、国外(E_3k)两种PAN纤维的直径及直径分布。结果表明,虽然两种纤维的直径相近,但直径分布不同,作为制取碳纤维的原丝,直径分布集中对提高碳纤维性能,降低不匀率更为有利。     

A study of spalling behaviour of PAN fibre-reinforced concrete by thermal analysis

Comparisons are made between polypropylene (PP) fibres and polyacrylonitrile (PAN) fibres in order to relate the thermal properties of fibres with the respective fibre mortar behaviour under thermal exposure. Thermogravimetry (TG), differential scanning calorimetry (DSC) and thermochromatography (ThGC) are utilized. When a cementitious fibre mortar is being heated, several physical phenomena occur in the temperature range between 100°C and 200°C. There is a significant difference in the thermal behaviour between PP and PAN fibres. PP fibres melt at 160–170°C. The non-melting behaviour of PAN fibre together with its rapid exothermic degradation reactions at around 300°C may add risk to the spalling of fibre mortar under rapid thermal exposure.     

Status and prospects for production of carbon fibres based on polyacrylonitrile

Production of PAN-based carbon fibres (CF) is a rapidly developing sector. Production in 2006 was 28,000 tons. The production capacities in 2007 increased to 55,500 tons and will attain 66,000 tons in 2008. The Japanese companies Toray, Toho, and Mitsubishi are the leaders and are responsible for 77% of total production. Toray is the leader with respect to fibre quality. The CF manufactured by the company basically have a strength of 500–560 kgf/mm². The properties of the PAN precursor are of decisive importance for the quality of the CF. Each company has its own PAN precursor plant for successfully competing. The fibre manufactured in the RF has a strength of 300–350 kgf/mm². Uglekhimvolokno NlTs has developed technology for production of CF with a strength of 450 kgf/mm². Economy in production of CF is attained by creating units (flow production lines) with individual capacity of 150–200 and even 400 tons/year (the capacity of existing domestic units is 10–20 tons/year). This increase in capacity is attained by using primarily new technical solutions, including conductive tempering of oxidized tows, separate air-oxidant and air-heat carrier circulation, making the PAN tow compact by selecting an appropriate oiling agent, and vertically positioning the carbonization furnace stack. The maximum modulus of elasticity of PAN CF is 60,000 kgf/mm². To attain high orientation and a high degree of crystallinity, boron, which decreases the temperature of transition of the fibre into the highly elastic state and thus facilitates the occurrence of orientation drawing and crystallite growth, should be used as a plasticizer. In semi-industrial conditions, when boron is added in the stage of oxidation in the form of boric acid, CF with a modulus of elasticity of 47,700 kgf/mm² are obtained. To prolong the lifetime of the graphite heaters, it is recommended that they be given a shape that allows focusing radiation on the processed fibre. Thin carbon fillers in the form of prepregs 0.04–0.17 mm thick and fabrics 0.11–0.15 mm thick are manufactured to increase the uniformity of the properties of multilayer composites. Prepregs made of “thick” PAN tow with a linear density of 3.2 ktex which are processed into CF with a strength of 500 kgf/mm², elongation of 2%, and modulus of elasticity of 23,000 kgf/mm², are the most economical. In the RF, unidirectional slivers of the Elur type 0.08 mm thick are manufactured for these purposes, but they have lower strength and due to the low processing speeds, high cost. These drawbacks have been eliminated in the semicontinuous method for manufacturing thin PAN fibres. __________ Translated from Khimicheskie Volokna, No. 1, pp. 20–26, January–February, 2008.     

中国腈纶的现状及未来

中国是世界最大的腈纶生产国,2007年腈纶产能为90万t,占世界腈纶产能的30.5%。中国腈纶在2006年出现负增长,腈纶在化纤行业所占比例不断缩小,腈纶全行业出现亏损。分析了其中的原因,认为是由于替代品的出现、劳动力紧张、关税、石化原料价格上涨等造成的,指出只有通过创新,中国腈纶才能有更好的发展。     

Heterogeneity of carbon fibre

A range of polyacrylonitrile (PAN) and pitch based carbon fibre types (high, standard and intermediate modulus fibres) have been characterised using both physical and chemical techniques, the results highlighting the heterogeneity of the fibre. Nano-indentation showed variation in stiffness between different fibres of the same type as well as variation along a 20 μm length of a single fibre. Tensile tests showed variance of approximately 25% in tenacity for three different carbon fibre types but less variability in modulus with values from 8% to 19%. Raman spectroscopy showed variation in the graphitic content both between fibres of different origin as well as variation, with 0.5 μm spatial resolution, along the length of a single fibre. Inverse gas chromatography surface energy measurements of larger samples of fibres were carried out using the novel approach of incremental surface coverage by varying the probe molecule concentration and revealed different levels of energetic heterogeneity for PAN based fibres collected at different stages of carbon fibre production. The heterogeneity of the unoxidised fibres (collected after carbonisation) was restricted to about 15% of the fibre surface whereas the surface oxidised fibre sample (collected after the electrolytic oxidation bath) was heterogeneous over more than 30% and the sized fibres were shown to be quite homogeneous.