聚氯乙烯塑化性能改善的研究

通过转矩流变仪测试方法研究了一种聚氯乙烯的复合加工改性剂对聚氯乙烯塑化性能的影响,结果表明,该复合加工改性剂不仅能使聚氯乙烯塑化性能得到改善,而且还能降低聚氯乙烯塑化时间、功率消耗以及塑化温度,提高聚氯乙烯塑化的质量,并且得到复合加工改性剂对聚氯乙烯塑化性能改善的最佳配比。     

一种茂金属聚乙烯用复合加工助剂的应用研究

研究了一种自制复合加工助剂对茂金属聚乙烯(mLLDPE)挤出性能的影响,并与进口及国产助剂进行对比.比较了不同加工助剂添加到wLLDPE中的单、双螺杆挤出特性.结果表明,加工助剂可以明显降低mLLDPE的挤出扭矩,消除挤出熔体破裂,改善薄膜制品的外观质量,研制的复合加工助剂具有较好的作用效果.     

浅谈复合电解加工技术研究现状

在日新月异的现代加工技术的发展下,单一的电解加工技术已经不能满足人们的加工要求,为了弥补其不足,复合电解加工技术应运而生,本文介绍了两种复合电解加工技术及其研究现状。     

散发香味的薄膜

<正> 日本石油化学公司(Nippon Petrochemical Co.)开发了一项加工芳香塑料膜的新工艺。 用专利方法把香料加在聚烯烃、PVC以及其它聚合物中加工成薄膜。还研制成功用香味化的纸复合加工成的复合薄膜。 这种芳香薄膜和复合香味纸的薄膜推荐用于包装花卉和水果,也可以制成瓶子和箱子的芳香标签,经轮压加工制成芳香邮票,明信片和散发香味的画片等等。     

含氟复合加工助剂的研制及应用

考察了不同的PPA、ACR及PPA含量对PPA／ACR复合加工助剂改性效果的影响。结果表明：复合加工助剂的最佳组成为PPAA－2、ACR401,复合加工助剂中PPAA－2质量分数为30％。     

电解-磁力复合研磨镍基高温合金实验研究

为了改善镍基高温合金GH4169制造零部件的表面质量,降低其表面粗糙度,提出了一种高效率的电解-磁力复合研磨光整加工方法。设计了电解-磁力复合研磨光整加工的试验装置,与单纯磁力加工对比,对不同加工工艺下所得合金表面的表面粗糙度、表面成分、表面残余应力进行分析。结果表明,在同等条件下,复合研磨使表面粗糙度由Ra 6.3μm降至Ra 0.8μm,完善了表面质量且加工效率提高56%;加工后表面成分无太大变化;使表面残余应力由+215 MPa转变为-186 MPa,从而获得更好的表面应力状态。     

过滤用玻纤复合针刺毡的研发

介绍了玻纤针刺毡的概念、特点及加工工艺。着重介绍了新型过滤材料一玻纤复合针刺毡的原料选择和加工工艺的确定。     

干式复合法中粘合剂的涂布

干式复合法是用二层不同性质的薄膜,通过涂布溶剂型粘合剂后复合成一种平滑无空气的复合薄膜的加工方法。本文就粘合剂的涂布方法,涂布量,固化处理作了阐述。     

复合钢板加工中常见裂纹及解决方法探讨

复合钢板是一种由基层钢板和复层钢板复合而成的双层金属钢板,本文针对复合钢板设备制作加工过程中常见的裂纹问题,从加工顺序、焊接工艺、坡口型式等方面分析了原因,并提出了解决的办法。     

塑料模具异型水路制作与应用

传统的塑料模具模冷却水路加工往往依赖于钻加工,加工中必须避免干涉到模具机构,钻加工方式是直线型的,不能均衡地降低模温,无法解决塑料制品中许多缺陷。分析了模具中异型冷却水路的原理,并阐述了加工制造过程。对复合加工技术在模具中应用、结合浇口套实例做了介绍,采用异型冷却水路复合加工技术可达到模具均衡冷却,用以提高塑料制品质量。     

丙纶/玻璃纤维包芯纱的研制

本文主要介绍了一种高性能包芯纱。它是以高性能纤维为芯纱、热融纤维为包缠纱,通过二维编织工艺加工而成。外层编织纱对高性能芯纱的保护使复合后的纱线的织造性能得到很大改善,可直接在二维或三维织机上进行织造。织物下机后经过热压成为热塑性复合材料。本文对丙纶/玻璃纤维包芯纱的纱线设计、纱线的几何模型进行了理论研究,确立了纱线结构参数的计算方法。     

Color pattern recognition for yarn‐dyed fabrics

In the process of designing and analyzing the yarn‐dyed fabric, the yarn color pattern has an important effect on the appearance of the fabric. An automatic color pattern recognition method for yarn‐dyed fabric is proposed in this study. The proposed method uses the fabric images obtained from a high‐resolution digital camera image acquisition system. The local statistical texture features are used for yarn texture segmentation. The yarn color classification problem is then formulated in a research framework of multiregion fuzzy segmentation, which can be added auxiliary variables and solved efficiently by the fast dual projection algorithm. The color values of the yarn crossing points are calculated by the yarn color classification results. The locations of the yarn crossing points are detected by a lightness gradient projection method. Different kinds of fabrics are tested in the experiments. Experiments on 14 actual fabrics show that the approach proposed in this study is effective for classifying yarn color and extracting the yarn color pattern in yarn‐dyed fabric.     

Color measurement of single yarn based on hyperspectral imaging system

This article proposed a novel approach to color measurement of a single yarn using hyperspectral imaging system (HIS). Due to the size of a single yarn, it is impossible for spectrophotometers to measure its color directly. The HIS can acquire the spectral reflectance of continuous bands within a region of interest on a yarn sample, which can achieve color measurement of a single yarn compared with traditional spectrophotometers. A single yarn is segmented from the background by a spectral matching method through adaptively setting threshold of Fréchet distance values. The spectral reflectance of single yarn is specified by a method that lightness of pixels used as weight. The experiment based on Pantone Cotton Chip Set shows that the interinstrument agreement between the HIS and a standard spectrophotometer Datacolor SF650 has a significant improvement after using the R-Model, and the average percentage improvement of the color difference is up to 54.99%. The yarn segmentation comparative experimental results show that the proposed method to segment single yarn from background is better in retaining the edge information of the yarn than the modified K-means clustering method, and the color of the yarn segmented by the proposed method is more similar to the actual color of single yarn.     

Investigation of wicking phenomenon and tensile properties in three-layer composite nanofibrous PA/PLLA yarn

One critical property of a nanofibrous structure is the wicking behavior in contact with liquids. This work's purpose is fabrication and investigation of tensile and wicking properties of a newly designed three-layer nanofibrous yarn consisting of polyamide 6/poly(L-lactic acid) (PA/PLLA) with a similar idea to Bobtex spun yarn structure in which adhesion between core (PA) and sheath (PLLA) is provided with a thin layer of polymeric thin film. The tensile strength and strain decreased 32 and 46%, respectively, in a three-layer yarn compared with two-layer, that is, yarn without the adhesion film. In addition, the ultimate strength of the three-layer yarn was higher than a PLLA yarn. The vertical wicking test for three-layer nanofibrous yarn reveals that at short times, capillary rise kinetics follow the Lucas–Washburn law while increasing the take-up velocity of the take-up roller in yarn fabrication leads to increasing the maximum height of water in yarn.     

浅析一步法涤纶异收缩混纤丝设备

介绍了一步法涤纶异收缩混纤丝设备的主要配置和结构特点,探讨了该设备中拉伸卷绕丝路的多样性设计。全拉伸丝(FDY)与预取向丝(POY)丝路单独控制、"双胞胎"组件、双丝室侧吹风、多种拉伸卷绕丝路选择等增强了异收缩混纤丝设备的一机多能。该机还可用于生产涤纶FDY、POY、中强丝、涤纶低缩丝等产品。     

Effect of single yarn twist and ply to single yarn twist ratio on strength and elongation of ply yarns

The amount of ply twist required to bring the surface fibers of the strand parallel to ply yarn axis is half the single yarn twist and, is experimentally verified by viewing the multifilament yarns longitudinally under Scanning Electron Microscope. The effect of single yarn twist and ply to single yarn twist ratio on strength and elongation of two‐ply cotton yarn have been studied. As the single yarn twist increases the tensile strength of the ply yarns with different levels of ply to single yarn twist ratio increases and at 130–140% of normal single yarn twist level, the ply yarns attain almost the same strength. Rate of improvement in tensile strength of cotton two‐ply yarn with respect to single yarn twist is more than that with respect to ply twist. The effect of ply to single yarn and cable to ply yarn twist ratio on strength and elongation of ply and cable multifilament yarns have been studied. Tensile strength of ply and cable multifilament yarns do not vary with the change in ratio of ply to single yarn twist and cable to ply twist respectively, particularly when the resultant yarn is finer. The cosine of average filament inclination to the ply yarn axis and that to the cable yarn axis do not vary much with different levels of ply to single yarn twist ratio and cable to ply yarn twist ratio respectively. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2245–2252, 2005     

聚乳酸长丝与亚麻-黏胶纱的并捻工艺及性能

采用并捻联合纺纱方法,将聚乳酸长丝与亚麻-黏胶单纱直接并合加捻成复合纱线,并对影响其纱线结构和性能的因素(捻因数、张力、钢丝圈)进行了研究分析,随后通过捻因数与钢丝圈正交试验优化得出最佳的并捻纺纱工艺。研究分析得出:并捻纱的断裂强力随着捻因数的增大先增大后减小;钢丝圈号数对并捻纱断裂强力存在着较大的影响;并捻纱的纱线结构类似于包缠纱,一般张力大的组分为纱芯,另一组分在外层螺旋包覆纱芯。最佳并捻工艺参数为:捻因数220,钢丝圈选14号。     

聚乳酸/天丝混纺纱混纺比与力学性能测试分析

聚乳酸(PLA)和天丝(Tencel)混纺纱的性能除了受到纤维本身和纱线捻度的影响,也跟纱线混纺比有很大关系。实验以不同混纺比的PLA/Tencel混纺纱为基本素材,进行力学性能测试,通过实验数据的分析,探索纱线力学性能随混纺比变化的规律。结果表明,标准状态下,混纺纱的强度随PLA质量分数的减少先减小后增大,混纺比在质量分数PLA60%/Tencel40%时,纱线强度降到最低点;混纺纱的湿强度随混纺比的变化趋势与干强度基本一致,临界混纺比相差也不大;混纺纱弹性回复率随PLA质量分数的减少,先增大后减小,PLA质量分数为70%时,纱线弹性回复率最大,纯Tencel纱线弹性回复率最小。     

Analysis of spinning process parameters on development of spun‐dyed PET yarn using the Taguchi method

The yarn tenacity of a spun‐dyed yarn is predicted from the spinning conditions and other properties of the yarn are analyzed through the defined parameters using the Taguchi method. To develop a spun‐dyed yarn using the Taguchi method, four factors that can largely influence the yarn properties are selected. From the experimental design based on four factors, the processes are executed to produce the specific yarns whose properties are measured to analyze the relationship between the process conditions and their results. The target properties of a spun‐dyed yarn may be obtained through adjusting the spinning parameters that are related to the yarn properties by the Taguchi tool. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:1419–1427, 2006     

Electrical conductivity of pure carbon nanotube yarns

The porosity of multi-walled carbon nanotube yarns can be varied over a wide range by adjusting the yarn construction, resulting in a dramatic change in yarn electrical conductivity. When the yarn electrical conductivity is converted into specific conductivity, its value remains approximately constant irrespective of the changes in yarn construction and porosity. The process of carbon nanotube yarn production involves two key steps, the formation of a network of carbon nanotube bundles spliced together by the entanglement of individual nanotubes and the compaction of the network into a cylindrical yarn. The splices formed from entangled individual nanotubes play a much greater role in electrical conduction than the cross-over contact formed between CNT bundles by compaction during spinning.