热处理对摩擦纺包芯纱性能的影响

讨论了DREF-3型摩擦纺包芯纱包覆层组分的比例(包覆率)以及在干、湿自然状态下热处理对纱热收缩性、包覆层抗滑脱性及拉伸性能的影响。芯纱采用聚酯长丝，包覆层为棉纤维。实验表明热处理能够明显提高纱线的热收缩性与包覆层抗滑脱性能，而且在湿状态下包芯纱的抗滑脱性能较干状态更好。纱断裂伸长随着处理温度的增加而增加。包覆率提高，纱热收缩性降低，抗滑脱性提高，断裂强力增加。     

织机摩擦对包芯纱强力及表面形态的影响

对不同细度的莱卡包芯纱、涤纶包芯纱,在小样织机上采用3种不同纬密进行无纬织造,纱线表面受到摩擦后,对纱线断裂强力、断裂伸长率、断裂强力下降率、断裂伸长下降率以及纱线外观形态进行测试分析。实验结果表明,包芯纱断裂强力随纬纱密度增加而减小,纱线强力降低率逐渐增大;纱线断裂伸长降低率随着纬密增加而增大。随着纬密增加,经过摩擦后,纱线的外包纤维变得松散,纱线紧密度降低,毛羽增加。对于相同线密度的包芯纱,在经纬密相同的条件下,纱线线密度越小,摩擦后包芯纱外观结构变化越小,纱线毛羽少。     

含涤纶长丝包芯纱织物的折痕回复性能

采用不同芯丝和纤维素类外包纤维,试制9种包芯纱及17种织物,对织物的急弹性折痕回复角和缓弹性折痕回复角进行测试,探讨纱线中涤纶含量、纱线线密度、芯丝线密度及织物干湿状态等对织物折痕回复性的影响。结果表明:通过以涤纶长丝为芯丝的包芯纱织制的含棉类织物,其折痕回复性能改善显著;随着所纺纱线中涤纶芯丝比例的增加,织物的折痕回复性逐渐提高;包芯纱织物在干态和湿态下的折痕回复角差异较大,随着纱线中涤纶比例的提高,织物在干态和湿态下的急弹性回复角、缓弹性回复角差异均逐渐减小。同时,织物中包芯纱的芯丝单丝线密度和芯丝成分、外包纤维等均会影响其折痕回复性能。     

基于低熔点涤纶长丝的棉涤氨包芯纱开发

采用低熔点涤纶长丝、氨纶长丝、棉纤维纺制5种不同长丝张力的复合包芯纱,并对纱线条干CV值、断裂强力、毛羽数等性能指标进行测试。优选其中两种棉涤氨复合包芯纱,分别织造纬平针织物,并对织物进行110℃热处理,测试织物热处理前后的基本性能。结果表明,低熔点涤纶长丝张力为20 cN、氨纶长丝张力为10 cN条件下制备的棉涤氨复合包芯纱性能最优,其纬平针织物经热处理后低熔点涤纶长丝产生热收缩,带动线圈收缩,织物线圈结构更加紧密,织物的抗起毛起球性能和力学性能均有所提高。通过简单热处理来改善针织物性能的方法效率高、能耗低、环保无污染。     

环锭纺Modal/涤纶包芯纱包覆率的纺纱工艺优化

目前,纺制Modal/涤纶包芯纱最普遍的生产方式是在传统环锭细纱机上纺制,但在生产中普遍存在包芯纱露芯等包覆不良的问题。为了改善纱线包覆不良,提高其包覆率,在研究了包芯纱包覆率的测量方法后,又根据环锭纺包芯纱的成纱机理,讨论了影响环锭纺包芯纱包覆率的主要原因和工艺因素,进而设计正交试验优化纺纱工艺以提高其包覆率,并对优化后的试样进行纱线性能测试,用于验证优化后生产工艺的可行性。     

热处理对大豆蛋白纱线性能的影响

为了解大豆蛋白纤维的热稳定性,采用多种热处理方法对大豆蛋白纤维纱线进行了处理试验.研究了大豆蛋白纤维纱线在松弛状态和张紧状态下,经过高温饱和蒸汽蒸纱、煮纱处理以及干热空气处理对纱线强伸性能和颜色的影响.结果表明:不同的热处理方法对大豆蛋白纤维纱线的强伸性、热收缩率、泛黄程度等指标均有不同的影响,因此,对大豆蛋白织物进行加工时,应选择适宜的加工方式和加工温度.     

不锈钢短纤维/棉包覆氨纶纱的弹性与电学性能

为开发兼具弹性和导电性能的电磁功能纱线,以氨纶为芯丝、外包不锈钢短纤维/棉混纺纱,研制系列弹性不锈钢短纤维/棉包覆氨纶纱。在Instron 5566万能试验机上,结合万用表,获得弹性纱线的应力-应变、应变-电阻以及定伸长弹性回复曲线,研究纱线在不同拉伸状态下的电学性能。结果表明:不锈钢短纤维/棉包覆氨纶芯丝的纱线,存在氨纶芯丝的断裂现象,将不锈钢短纤维/棉包覆氨纶芯丝的纱线直接与氨纶丝或氨纶/棉包芯纱直接并合的方式,赋予纱线弹性;随着不锈钢短纤维含量的增加,弹性纱线的弹性伸长和回复性能都降低,塑性变形增加;随着弹性纱线应变的增加,其电阻先增加后降低。     

低熔点涤纶包芯纱的生产工艺及性能研究

探讨纺纱工艺参数对低熔点涤纶包芯纱质量的影响。以40 tex的涤纶包芯纱为例,分析改变外包低熔点涤纶短纤维含量、纱线捻系数及热处理工艺对涤纶包芯纱断裂强力与毛羽的影响。试验结果表明:经热处理后的纱线断裂强力提高了5.64%,且1 mm毛羽数降低了28.59%。认为:将低熔点涤纶短纤维与常规涤纶短纤维混纺作为外包纤维层,对涤纶包芯纱的断裂强力与毛羽均有改善。     

芯纱刚性对包芯纱的包芯性及织物悬垂性的影响

在环锭细纱机上试生产了几种不同芯纱的毛型包芯纱，并试织了相对应的织物。通过测试这些毛型包芯纱的不同芯纱的抗弯刚度，找出了芯纱抗弯曲性能对芯纱包覆效果和对织物悬垂性能的影响。研究了芯纱抗弯曲刚度与芯纱包覆效果和织物悬垂性的关系。     

不同涤粘纱线的结构与性能

为了探究不同结构对纱线条干、捻度、毛羽、芯吸、拉伸以及抗弯性能的影响,以涤纶和粘胶纤维为原料分别纺制了混纺纱、短纤维/短纤维包芯纱与长丝/短纤维包芯纱3种纤维含量比例相同、结构不同的纱线,对不同纱线进行结构与相关性能测试结果。比较分析发现,混纺纱中的涤纶短纤维随机分布在粘胶纤维中;涤粘短纤维/短纤维包芯纱包覆效果良好且芯层涤纶短纤会向皮层粘胶纤维中发生一定程度的转移;涤粘长丝/短纤维包芯纱中涤纶长丝抱合紧密且有“露丝”现象;涤粘短纤维/短纤维包芯纱条干CV值最大,捻度变异系数和不匀率最小;涤粘混纺纱的毛羽数量最多,芯吸高度最大;涤粘长丝/短纤维包芯纱的断裂强度和断裂伸长率最大,而涤粘混纺纱的抗弯力最大。     

Studies on cotton–acrylic bulked yarns produced from different spinning technologies. Part I: yarn characteristics

The effects of different factors, namely spinning technologies (ring, rotor and DREF-II, i.e. Group A yarns), position of shrinkable acrylic feed sliver in DREF-II friction spinning system (Group B yarns) and proportion of shrinkable acrylic core fibre in core-sheath type DREF-III friction spun yarns (Group C yarns) on various properties of cotton-acrylic–blended bulked yarns have been studied. The bulk in the yarns was developed by relaxing shrinkable acrylic component of the yarns using boiling water treatment. All the above factors have a significant impact on various properties of cotton–acrylic blended bulked yarns. For all the yarns, after boiling treatment, there is lengthwise shrinkage of yarns and the specific volume also increases. Tenacity and breaking elongation of all the yarns of Group A and Group B increase after hot water treatment, whereas in case of core-sheath type DREF-III yarns (Group C yarns) there is drop in tenacity and breaking elongation after similar treatment. In general, for all the yarns the flexural rigidity of the yarns reduces and compressibility and compressional recovery of increases after bulking treatment.     

Cut resistance of hybrid para-aramid fabrics for protective gloves

This paper deals with cut resistance of hybrid woven para-aramid fabrics tested according to the appropriate clause of EN 388 – “Protective Gloves against Mechanical Risks”. Abrasion, puncture and tear resistance properties of the fabrics were also measured. The experimental sample set was plain-woven fabrics made of hybrid yarns composed of staple para-aramid fibres with different core/sheath ratios of various filaments in their structure. The effects of core/sheath ratio and core filament type were investigated. The results revealed that decreasing core–sheath ratio of the hybrid yarns led to the increase in weight and thickness, resulting in improved cut, abrasion and puncture resistance properties. It was confirmed that cut resistance increased with the increase in thickness and weight of the fabric. Para-aramid/Dyneema® fabric had higher cut, abrasion and puncture resistance properties.     

Studies on cotton–acrylic bulked yarns and fabrics. Part I: Yarn characteristics

The effect of variables, namely yarn fineness, shrinkable acrylic proportion and twist level, on various properties of cotton–acrylic blended bulked yarns has been studied by relaxing shrinkable component of the yarns using boiling water treatment. A three-variable factorial design technique proposed by Box and Behnken was used to investigate the combined interaction effect of the above variables on the properties of these yarns. The design variables were optimized for all the yarn properties by using the response surface equations. The shrinkage percentage of yarn was found to be higher in the case of coarser yarn, yarn with higher proportion of acrylic fibre and higher twist level. During bulking treatment as the yarns shrink, the effective number of twist per unit length also increases significantly. It is observed that the specific volume of the yarn increases with an increase in the acrylic proportion and decreases with an increase in the twist factor. The breaking extension increases significantly after bulking with a slight increase in tenacity. The flexural rigidity and initial modulus of yarn considerably decrease on bulking. The vertical wicking heights for all the bulked yarns were found to be higher than comparable 100% cotton yarn.     

Analysis of thermal comfort properties of fabrics for protective applications

Protective clothing protects the body from external influence like heat, chemicals, mechanical hazards, bad weather, etc. by shielding the human body from harsh environmental effects. The maintenance of thermal balance is one of the most important aspects of protective clothing. The study aims to investigate the thermal comfort properties of woven hybrid fabrics produced with high performance core spun yarns. For this purpose, meta-aramid, e-glass, Technora® and Dyneema® fibres were combined using core yarn spinning method in order to enhance the protective performance characteristics. The effects of the core/sheath ratio and type of core materials on the thermal comfort characteristics were investigated and evaluated statistically. The results revealed that, core/sheath ratio, types of core materials have significant effects on thermal comfort characteristics of the fabrics. As the core ratio increases from 19 to 56%, the air permeability of the fabrics increases whereas their thermal conductivity and thermal absorptivity properties decrease. Meta-aramid/E-glass core fabrics can be preferable for protective clothing due to high air permeability and thermal conductivity values.     

Packing of micro-porous yarns. Part II: optimization of fabric characteristics

This paper is concerned with the study of the characteristics of plain woven fabric produced with micro-porous cotton yarns in weft. The micro-porous yarns with varying packing densities and level of pore volumes are produced by changing proportion of PVA fibre content in the blend, yarn twist multiplier (TM) and spindle speed at ring frame. The micro-pores within the structure of the yarn have been created by dissolving the PVA fibres using washing treatment in hot water. A three-variable factorial design technique proposed by Box and Behnken has been used to study the interaction effects of these variables on the characteristics of fabrics. The influence of these three variables on the mechanical, handle and comfort properties of fabrics are studied, the response-surface equations for all the properties have been derived and the design variables are optimized for various fabric properties. Improvements in bending resistance, abrasion resistance and compressional characteristics have been observed with incorporation of micro-pores within the yarn structure. These fabrics with micro-pores have improved thermal resistance and moisture vapour transmission compared to that of 100% cotton fabric.     

Tensile characteristics of Dref‐III friction core‐spun yarns

The tensile characteristics of Dref‐III friction spun yarns with jute as core and cotton as sheath components have been studied. Three yarns with different core–sheath proportions such as 55/45, 65/35 and 75/25 jute/cotton friction spun yarns were produced by using the Dref‐III friction spinning system. The influence of core and sheath components on the tensile properties at three different traverse rates at 150 mm/min, 750 mm/min and 1500 mm/min, respectively, have been reported. The work of rupture and specific work of rupture at break of these yarns were also analysed. From the test results, the maximum work of rupture was found in 55/45 core–sheath (jute/cotton) friction spun yarn when compared to 65/35 and 75/25 core–sheath (jute/cotton) friction spun yarns. It is due to the higher core–sheath interaction factor (CSI_T = 26.14) and better yarn‐packing density because of higher proportion of cotton fibres in the sheath component. The breaking tenacity and contribution factor of core and sheath component (CSI_T) of jute/cotton friction spun yarns were also analysed using multivariable ANOVA analysis.     

Tencel纱线强伸性能探讨

通过实验比较分析了Tencel、粘胶、棉纱线的强伸性能，结果表明Tencel纱线湿强下降明显小于粘胶纱线，热处理后Tencel纱线的断裂强度、断裂伸长率有下降趋势，但小于粘胶纱线的变化量。     

Packing of micro-porous yarns: Part I. Optimization of yarn characteristics

The present paper deals with the factors affecting the packing of a micro-porous yarn, namely proportion of PVA fibre content, yarn twist multiplier (TM) and spindle speed at ring frame, and with their combined effect on various properties of the yarn. The micro-pores within the structure of the yarn have been created by dissolving the PVA fibres using washing treatment in hot water. A three-variable factorial design technique proposed by Box and Behnken is used to investigate the combined interaction effect of the above variables on the properties of the yarn. The present experiment variables, namely proportion of PVA fibre, yarn twist multiplier (TM) and spindle speed, were found to have significant impact on various properties of yarns before and after wash. For yarns before wash, the specific volume reduces with the increase in the PVA content, yarn twist and spindle speed. In the case of yarns after wash, there is reduction in the yarn specific volume with the increase in TM and spindle speed, but with the increase in the PVA percentage the yarn specific volume increases. The tenacity of yarns before wash increases with the increase in the PVA content, but for yarns after wash, the proportion of PVA content has comparatively less influence. The compressibility of yarns before wash reduces with the increase in the PVA content, but a reverse trend is observed in the case of yarns after wash. The design variables were optimized for all the yarn properties by using the response surface equations.     

Effect of blend proportion on thermal behaviour of bamboo knitted fabrics

This study presents the thermal comfort properties of single jersey knitted fabric structures made from cotton, regenerated bamboo and cotton–bamboo blended yarns. Cotton, bamboo fibre and blends of the two fibres (100% cotton, 100% bamboo, 50:50 cotton:bamboo, 67:33 cotton:bamboo, 33:67 cotton:bamboo) were spun into yarns of identical linear density (20?tex). Each of the yarns so produced was converted to single jersey knitted fabrics with loose, medium and tight structures. The thermal conductivity of the fabrics was generally found to decrease with increase in the proportion of bamboo fibre. The relative water vapour permeability and air permeability of the fabrics were observed to increase with increase in bamboo fibre content. Statistical analysis also indicates that the results are significant for air permeability, thermal resistance, thermal conductivity and relative water vapour permeability of the fabrics.     

Comparison of thermal comfort properties of single jersey fabrics produced by hollow yarns with different hollowness ratio

In this study, the thermal comfort properties of single jersey fabrics produced by conventional and hollow cotton yarns with different hollowness ratio have been investigated and compared. For this purpose, thermal conductivity, thermal resistance, thermal absorptivity, air permeability and water vapour permeability of core spun, hollow and conventional yarn fabrics were measured and evaluated statistically. It was observed that thermal comfort properties of single jersey fabrics were affected by the yarn structure and the fibre distribution within the yarn. The results showed that hollow yarn fabrics had better thermal comfort properties than that of conventional yarn fabrics. In hollow yarns, as the hollowness ratio increases, air permeability and thermal conductivity of single jersey fabrics decrease but thermal resistance, thermal absorptivity and water vapour permeability increase. Statistical analysis also indicated that the differences between properties of hollow yarn fabrics and conventional yarn fabrics were significant. Furthermore, the yarn hollowness ratio significantly affects thermal comfort properties of single jersey fabrics.