尼龙66纤维的高速纺丝研究(I)——纺程上的结构发展

对尼龙66进行了700—6100m/min的纺丝,在线测定了纺丝线上丝条的直径、温度和双折射,并对初生纤维进行了密度测定,用DSC对纺丝切片进行了静态结晶行为的分析。结果表明,纺丝线上的细颈现象不明显。当纺速一定时,纺丝线上开始结晶的位置随熔体挤出量而变化。且影响结晶行为的主要因素是冷却速率而不是丝条应力。

凝胶染色过程中腈纶沿纺程的结构性能变化的研究

采用湿法纺丝工艺制备腈纶(即聚丙烯腈(PAN)纤维),研究了凝胶染色过程中PAN纤维在不同工序段的结构和物理性能。结果表明:沿着纺程,PAN纤维的直径逐渐减小,纤维的玻璃化转变温度和结晶度逐渐提高;在水洗后PAN纤维表面有明显的微观结构缺陷、且无定形区占比高;经过热拉伸和干燥致密化之后,纤维致密化,结晶度大大增加,凝胶染色后的PAN纤维染色均匀,且色泽良好,成品PAN纤维对羊毛、PAN纤维、聚酯纤维、尼龙纤维、棉纤维、醋酯纤维的沾色牢度为4~5级;PAN纤维力学性能沿纺程变化主要取决于纺程上各工序的工艺变化,凝胶染色不影响纤维的断裂强度和断裂伸长率。

改变纺程参数制取高模量低收缩PET纤维

介绍在高速熔融纺丝线经过的空气介质中设置液体等温槽以改变纺程参数，制取高性能聚对苯二甲酸乙二醇酯（ＰＥＴ）纤维的一种新工艺，制得的初生纤维具有优异的力学性能。分析了此法制得的纤维的结构和力学性能的变化以及工艺条件的影响，指出其性能的提高是由纤维结构中取向非晶态含量大大增加所引起。对制得的初生纤维进一步拉伸热处理后，其性能优于一般高模量低收缩ＰＥＴ纤维。

PP/PS共混熔纺中相结构沿纺程的梯度演变

将聚丙烯（PP）/聚苯乙烯（PS）按质量比92∶8进行共混纺丝,以自制的纺程取样器对PP/PS熔融纺丝进行纺程取样,利用冷冻超薄切片机获得纺程各点取样纤维的横截面和纵剖面,扫描电子显微镜观察纤维中PS分散相的形貌,研究了共混熔融纺丝中梯度结构沿纺程的演变及其梯度结构的形成机理。结果表明：PS分散相数目沿纤维径向呈现内密外疏的梯度分布,这一差异沿着纺程不断增大;PS分散相在纺程0~60 cm发生形变,纺丝速度为125~500 m/min下PS分散相直径逐渐减小,当纺丝速度达到1 000 m/min时,PS分散相直径在纺程0~20 cm减小,在纺程20~60 cm增加,PS分散相液滴在此区域发生了明显的聚并,在纤维表层各个纺丝速度下分散相都呈现不同程度的聚并现象;在PP/PS共混纤维中呈现中心层分散相液滴形变程度大表层形变程度小的梯度差异,但高速纺丝会弱化这一差异。

纺程加热聚酯纤维的结构和性能

本文叙述了在3200m/min纺速条件下距离喷丝板500mm左右设置热板进行纺程加热时纤维的物理性能,分析了随加热温度和张力变化而引起的纤维结晶度、晶粒尺寸和双折射率、声速取向等变化的原因.

纺程加热拉伸技术现状及未来

介绍了国内纺程加热拉伸技术的现状、技术特点和存在的问题,与其它几种高速纺技术进行了对比,并对这项技术的开发提出了合理性建议。对传统型纺丝机的技术改造有一定的参考价值。

POY纺丝设备改造为纺程加热式纺丝卷绕一步法设备可行性研究

纺程加热法热制充分结晶ＰＥＴ纤维现有三种不同工艺：热板加热法（ＦＣＹ）；热管加热法（ＴＣＳ）；热板加热并加张力法（ＦＳＹ），均能基本达到纺丝卷统一步法（或称ＦＤＹ）的要求。介绍了各种纺程加热法的工艺流程及条件。由于加工工艺的不同，导致了产品性能和结构的差异，对此作了技术分析。分析了ＰＯＹ设备技术改造为纺程加热式一步法设备的可行性，并对改造费用和经济效益进行了预测。指出伴随着ＰＯＹ及其ＤＴＹ产品市场的低迷状况，这一技术改造具有十分可观的前景。

关于熔体纺丝中纺程长度的分析

从热交换的角度出发,可以从理论上计算熔体纺丝时的冷却长度,实测数据也证明了这个计算是正确的,从而证实熔体纺丝时缩短纺程的可能性。

花色纺丝II.冷管热管纺丝张力不匀及工艺调节

冷管与热管上纺丝因不同的纺丝温度导致纤维的张力不同 ,丝条集束后在卷绕时引起卷绕成型不良。为解决由于采用新工艺所产生的卷绕张力不匀 ,在不同的纺丝工艺下 ,利用计算机对纺丝成形张力进行了数学模拟计算。计算结果显示 ,改变冷管的直径和起始位置 ,对卷绕张力无调节作用 ,且不影响纤维的结晶和取向 ,而改变热管直径 ,对卷绕张力也无调节作用 ,但使快速结晶时的位置沿纺程后移。因此 ,需要在集束点之前加装一个张力调节补偿装置 。

我国复合短纤维生产概况

介绍我国商业化复合短纤维工业现状 ,皮芯型、并列中空型双组分复合短纤维生产工艺技术和产品应用情况。建议国内生产复合短纤维选择长程纺 ,并加强对复合短纤维下游产品的研究开发。

Motion Analysis of Fiber Band in Compact Field of Compact Spinning

The technological process of compact spinning and the compact procedure of fiber band in compact field are briefly illustrated. The motions of fiber band in compact field are discussed theoretically from which tilting angle of suction slot in profile tube, additional twists created by fiber band’s rotating around its own axis and ultimate twists in compact yarn are deduced accordingly. The existence of additional twists is also verified through experiments.

Dynamic Fault Model for On-Line Evaluation of Yarn End Breakage during Ring Spinning

In this paper, a dynamic fault model is proposed to predict yarn end breakage in the spinning procedure through investigation of fault characteristics. In view of the principle that uniformity bad in raw material causes iustable yarn formation, the investigation focuses on the fault characteristic existing in the dynamic tension. Analyzing the dynamic spinning system, the phenomenon of over random shock in a spinning triangle is discovered to be the main physical event prior to yarn end breakage. The fault characteristic is further confirmed by dynamic tests and signal processing, and can be used to make an approach to predicting yarn end breakage. A relative energy feature is defined for evaluating the tendency of yarn end breakage, and its effectiveness is verified by on.line monitoring tests in the laboratory. The research results show that the proposed dynamic fault model has not only an advantage in indicating the presence of fault characteristics, but also great potentials in quantitating fault in online spinning monitoring.

Increasing the Energy Efficiency of Air Jet Weaving Based on a Novel Method to Exploit Energy Savings Potentials in Production Processes of the Textile Industry

This article deals with the energy efficiency of textile weaving machines. A method based on exergy balances has been developed at the Institute for Textile Technology RWTH Aachen University （ITA）, Aachen, Germany in order to improve energy efficiency textile machines. The relay nozzles of the air-jet weaving technology need up to 80% of the energy of the weaving machine. At ITA, a new nozzle concept was developed. The developed geometry is a so called High-Volume-Low-Pressure nozzle （HVLP nozzle）, based on convergent nozzle aerodynamic theory. With this concept, energy savings up to 30% are possible.

Study on the Rotor Spinning Processing of Spun Silk/Cashmere Blended Yarn

This paper studies rotor spinning blended yam produced of spun silk and cashmere. Nine samples were spun, from three different opening rollers and different navels. According to the Uster test results of yam quality properties, optimum selection is done by using analysis method of combining fuzzy decision-making and fuzzy pattern classification. Experimental plan is designed based on universal rotated experimental design, and the method of confined optimization is used to optimize the speed of opening roller, the speed of rotor and twist factor, according to the results of yam quality test by Uster.

The study of relationship between textile and garment market,industry cluster and regional economy development

China＇s textile and garment markets grown up with the development of reform and opening-up, they＇re well adapted to the national policy and economic environment in each period, and formed a large-scale development, played a positive role in promoting China＇s economy development. This paper has a research on the textile and garment market, industry cluster and regional economy, recognize textile professional market and regional economy as the main research object, industrial cluster as the intermediary variable. Establish textile and garment market, industrial cluster, regional economy as the main trunk of structural equation model and carry on the empirical analysis. From the empirical analysis, this paper find that the coefficient of textile and garment market effecting on industrial cluster is 0.91, and industrial cluster on regional economy is 0.93, that means results verify hypothesis relationships between the three of them Finally, according to each path coefficients, providing relevant suggestions for the Shanghai area development of textile and garment market, related industries cluster and regional economy development.

Sound Absorbing Composites from Nonwoven and Cellulose Submicrofibres

This paper describes possibility of utilization of waste natural fibres in production of sound absorbing composites. Waste flax fibres were modified by enzymatic treatment, after which they became more short and fine. This form of fibres can create good sound absorption. Preliminary studies concerned an application of cellulose fibres after enzymatic treatment as the filling of thermoplastic sound absorbing composites. The conditions of composite manufacturing process from multilayer structure （matrix nonwoven/submicrofibres layer） were developed. The influence of submicroflbres content in the composite on the scale of the improvement of its sound absorption property was investigated. Results showed that for the same conditions of the composite manufacturing process and similar composite thickness, gradual increase in content of that filling leads to adequately increase in sound absorption coefficient of the composites. The composites could be applied among others to accommodations and transport facilities.

Integration between Engineering and Knowledge Systems： Evaluation of Performance of a Wastewater Treatment Plant in a Textile Company

The integration between engineering and knowledge systems （KS） in a manufacturing environment in a network of industrial enterprises was investigated. The drivers for this application of engineering design to infrastructure in an industrial setting where cost and time to market are vital were to spread best practice, and to gain experience in dealing with the regulatory authorities according to ISO 14000. Therefore, the aim of this study was to evaluate the performance of the industrial wastewater treatment plant of the Hilla Textile Factories, to find an appropriate method of treating the industrial wastewater so as to render it fit for reuse or safe to be disposed of as stipulated by the Iraqi laws on effluent disposal. The removal efficiencies of the different parameters used to describe water quality was low. It was found that the removal efficiency of COD （Chemical Oxygen Demand） was 20-21%, that of BOD （Biochemical Oxygen Demand） was 17-30% and that of TSS （Total Suspended Solids） was 27-31%. The quality of the effluent was not in line with those of either the Iraqi or American standards.

Engineering Quality and Knowledge Systems： An Appraisal for Improving the Spinning Stage

The industrial organisations have a vested interest in quality and its practices in making a quantum leap, thereby requiring proper refocusing and rethinking. This is targeted seriously towards firms acquiring Knowledge Systems （KS） in order to nurture the employees＇ capabilities. Therefore, to enhance performances and their highly creative direction takes consideration of QE （quality engineering） and KS and disciplines complementary to each other. Additionally, the flow of operations and activities of the KS through the application of quality engineering （QE） principles is according to the view of Japanese engineer Taguchi. This aims to achieve good quality in the product design and processes, and also to anticipate problems that may occur before the shipping of the products. In this study, the use of quality control engineering and Taguchi＇s function methods in determining these properties and the loss caused by the company will be examined. However, the adopted approach of study scope to the society will aid KS. Also, efforts in this direction motivate the employment of a statistical method by Taguchi which relied on the principle of target-oriented quality, representing the value characterising the product quality.

喷头拉伸对超高分子量聚乙烯后续牵伸的影响

利用干法纺丝制备超高分子量聚乙烯纤维,研究了喷头拉伸对超高分子量聚乙烯后续牵伸的影响。通过张力仪测量不同喷头拉伸倍率下的张力,计算出拉伸应力。利用拉伸应力—粘滞二元组合模型,计算机拟合出NSkT值,根据该值确定喷头拉伸倍率。结果发现,13倍的喷头拉伸能够使最大后续牵伸倍率达到23.3倍,最终的纤维强度和模量分别为30cN·dtex-1和1200cN·dtex-1。

Solution of Spin and Pseudo-Spin Symmetric Dirac Equation in (1＋1) Space-Time Using Tridiagonal Representation Approach

The aim of this work is to find exact solutions of the Dirac equation in(1+1) space-time beyond the already known class.We consider exact spin(and pseudo-spin) symmetric Dirac equations where the scalar potential is equal to plus(and minus) the vector potential.We also include pseudo-scalar potentials in the interaction.The spinor wavefunction is written as a bounded sum in a complete set of square integrable basis,which is chosen such that the matrix representation of the Dirac wave operator is tridiagonal and symmetric.This makes the matrix wave equation a symmetric three-term recursion relation for the expansion coefficients of the wavefunction.We solve the recursion relation exactly in terms of orthogonal polynomials and obtain the state functions and corresponding relativistic energy spectrum and phase shift.