A Study of the Mechanical Properties of Woven Silk Fabrics. Part III: A Study of the Extensibility of Continuous-filament Woven Silk Fabrics in the Small-load Region

Continuous–filament woven silk fabrics have a very low tensile modulus in the small-load region compared with woven fabrics of other fibres having a similar structure. In the silk fabrics, there may exist a small gap between the warp and weft threads at their crossover points because of the sericin-removing treatment that is applied after weaving. The tensile behaviour of a fabric with such a gap is considered to consist of two stages. In the first stage, the bent yarn alone is stretched in the initial state of tensile deformation without any mechanical interactions between the warp and weft threads. Since the bending rigidity of silk yarns is small and the gap is relatively large, the tensile modulus of silk fabrics becomes very low in the initial tensile region. After the contact of the warp and weft threads, the soft lateral-compressional property of the silk threads leads to extensibility of the silk fabric. This stage is called here the second stage, in which the tensile and the lateral-compressional deformation properties are mainly concerned with the tensile behaviour of the fabric in this region. Silk–fibroin fibre has a small fibre crimp, and this crimp also makes the silk yarn compressible. In this paper, the extensibility of silk fabrics is analysed, with a theoretical estimation of the extensibility, and an experiment to explain the reason for the high extensibility of silk fabrics is reported.     

Evaluating the crease recovery performance of woven fabrics considering bending behaviour in various directions

Since the woven fabric is used on the 3D body, it encounters bending deformation and crease in various directions. Due to the prominence of these deformations in the appearance of the garment, the inspection of bending and crease recovery behaviour of fabric in different directions needs to be considered. In this paper, the evaluation of bending rigidity and crease recovery of fabrics is carried out in various directions. Analysis of the results revealed that fabric-bending rigidity could be expressed as a sinusoidal function of sample orientation towards warp direction. For all the studied fabrics, from warp axis to bias direction, bending rigidity follows a descending trend, however; crease recovery angle has an ascending tendency. Reverse variations were achieved for both properties from bias direction to weft axis due to the variant warp and weft yarn contributions in each direction. Hence, the lowest bending rigidity was obtained in the bias direction (45°), while the highest crease recovery angle was recorded for the mentioned direction. Moreover, an exponential function is utilized to express the non-linear relation between bending rigidity and the crease recovery in different directions of the fabric. The statistical analysis of the results clarified that the effect of fabric direction and structural parameters on the bending and crease recovery behaviour is significant in the confidence range of 95%.     

石墨烯黏胶纤维机织物的功能改性研究

制备同规格的普通黏胶纤维机织物、石墨烯黏胶纤维机织物及不同不锈钢丝质量分数的石墨烯黏胶纤维/不锈钢丝机织物,对比它们的导电、防电磁辐射、防紫外线、抗静电、力学(拉伸、弯曲、耐磨)及透气等性能。结果表明:普通黏胶纤维经石墨烯改进后,所制成的石墨烯黏胶纤维机织物的导电、防电磁辐射、防紫外线、抗静电、力学(拉伸、弯曲、耐磨)等性能都有所改善,其中防紫外线与耐磨性能提高显著,透气性能下降明显;石墨烯黏胶纤维/不锈钢丝机织物的导电、防电磁辐射、防紫外线和抗静电、经向拉伸断裂强力、纬向抗弯刚度、透气性能都优于石墨烯黏胶纤维机织物,纬向拉伸断裂强力、经纬向拉伸断裂伸长率、经向抗弯刚度及耐磨性能不及石墨烯黏胶纤维机织物;随着不锈钢丝质量分数在7.0%~20.0%范围内的增加,石墨烯黏胶纤维/不锈钢丝机织物的导电、防紫外线、抗静电、经向拉伸断裂强力、纬向抗弯刚度及透气性能增强,纬向拉伸断裂强力、经纬向拉伸断裂伸长率、经向抗弯刚度、耐磨性能减小,不锈钢丝质量分数变化对防电磁辐射性能影响较小。当不锈钢丝质量分数为7.0%时,石墨烯黏胶纤维/不锈钢丝机织物的综合性能最佳。     

制服类面料低负荷下的力学性能对服装成形性的影响

通过KES系统研究了不同织物密度和后整理工艺调整对织物经纬向在低负荷下的拉伸、弯曲、剪切性能的影响,制作了曲面造型,分析了不同性能的织物曲面造型的难易程度.研究表明,面料在低负荷下的力学性能,尤其是剪切性能直接影响了面料制成服装的成形性.且同一种织物存在最佳工艺配制点,超过这个点后,某一类型服装造型的成形性显著降低.织物经、纬向的弯曲和剪切性能相互影响显著,经密或纬密变化将同时导致经向和纬向2个方向上的弯曲和剪切性能变化,而经、纬向拉伸性能则相互影响较小.对于制服类面料,尤其是适体性的制服类面料,应该注意到织物在低负荷下的力学性能,并进行规范.     

风格仪转速与织物悬垂性的关系研究

以16块织物为研究对象,用KES-FB风格测试系统测试了织物的拉伸性能、剪切性能和弯曲性能,运用YG(L)811-DN织物动态悬垂风格仪测试了5个转速下各织物的悬垂系数和波纹数,通过相关分析和方差分析研究了转速对织物悬垂系数与波纹数的影响,结论如下:随转速的增加,织物悬垂系数基本呈线性增加;试样结构参数与织物悬垂系数增加率之间的相关性不明显;而经向弯曲刚度及经、纬向剪切刚度与悬垂系数增加率有显著负相关关系,转速对波纹数没有显著影响。     

Development of woven stretch fabrics and analysis on handle,stretch, and pressure comfort

Twelve stretchable fabrics are woven in two sets with one set in 50^s and 60^s 100% cotton in warp and 40^s, 50^s, and 60^s cotton core spun lycra yarn in weft and another set with 2/75 and 2/120?Nm silk in warp with 40^s, 50^s, and 60^s cotton core spun lycra yarn in weft. Hundred percent cotton sari blouse materials commercially available in the market are also included for a comparative study of pressure distribution between cotton core spun lycra fabrics and cotton blouse materials. The influence of fabric specification on total hand value (THV), stretch properties, and pressure comfort is analyzed. The effects of body shape and fabric mechanical properties on garment pressure are also analyzed. The results indicated that the finer counts of cotton core spun lycra woven with cotton and silk to elasticize fabrics provided improved hand feel, stretch, and pressure comfort values. The average pressure value of the samples at the major pressure points with the cotton/cotton core spun lycra samples and silk/cotton core spun lycra samples is lower than 100% cotton samples’ fabric physical properties, stretch properties, mechanical properties, and THV significantly influenced the pressure distribution and comfort of garments.     

纳米TiO2抗菌棉织物服用性能探讨

为探讨纳米抗菌棉织物的服用性能,利用FAST系统测试纳米TiO2整理前后棉织物在低负荷条件下压缩、弯曲、剪切、延伸等力学性能以及相关结构参数和尺寸稳定性.实验结果表明,整理后面密度、纬密、表面厚度、弯曲、可成型性、纬向剪切和纬向松弛收缩率有不同程度的提高;而与经向成45°的剪切刚度、经向松弛收缩率和湿膨胀率有所下降.从...     

Hand feeling style of spun silk/chitosan blended fabric北大核心CSCD

Spun silk and chitosan fiber were blended to fabricate spun silk/chitosan blended yarn with three blending ratios (90/10 and 80/20 and 70/30) by silk spinning technology. The silk/chitosan blended yarn and pure spun silk were used as warp and weft yarn to design and weave 16 fabrics. The 16 mechanical properties about fabric hand feeling were measured at low stress with KES-FB-AUTO fabric style instrument. Six basic style values (stiffness, flatness, suppleness, fullness, smoothness and scroopy) were calculated by Kawabata formula of women's fine dress fabrics. The results reveal that compared with a pure spun silk fabric, spun silk/chitosan blended fabrics have higher stiffness, flatness, smoothness and scroopy, but lower suppleness, and the fullness differs little. © 2017 China Silk Association. All rights reserved.     

A Study of the Mechanical Properties of Woven Silk Fabrics. Part II: Analysis of the Shearing Properties of Woven Silk Fabrics

The gap between the warp and weft threads at their crossover points in woven silk fabrics is responsible for the very low values of shear stiffness and hysteresis of shear force in these fabrics. The existence of this gap is proved by using shear–deformation theory and making experiments on silk fabric. A quantitative determination of the gap is obtained by using strip–biaxial–extension experiments and measuring the retardation strain. The gap observed for woven silk fabrics is 6–7 μm. Since microscopical observation of the cross–section of silk fabrics does not show the gap, the gap measured by mechanical methods is called an “effective gap”. The gap has a strong effect on the mechanical properties of silk fabrics, especially their shear properties. It also emphasizes the good handle of silk fabrics.     

PTT/绢丝混纺织物的风格及服用性能

为了将PTT纤维的形状记忆性与蚕丝优异的服用性能相互融合,以绢纺工艺将PTT纤维与绢丝混纺,制成混纺比为50:50的PTT/绢丝混纺纱,并以其为经纬纱设计织造了5种PTT/绢丝混纺面料,此外还以相同规格织造了3种纯绢纺纱对比试样。测定了这8种织物的手感、悬垂性及保形性(折皱回复性、拉伸回弹性)、透通性(透气、透湿性)和抗起毛起球性能,对比分析了PTT/绢丝混纺织物和纯绢丝织物的风格和服用性能。研究结果表明：PTT纤维对绢纺织物的风格与服用性能有良好的改善作用,与纯绢丝织物相比,PTT/绢丝混纺织物的折皱回复性、拉伸回弹性提高,柔软性和悬垂性好,滑糯性、透通性和抗起毛起球性能略差。     

挠性剑杆织机织制高经密丝织物的研究

研究了高经密丝织物在挠性剑杆织机上织制时产生纬丝拉毛圈问题的原因 ,通过优化织造工艺参数、改进剑头结构 ,对常见的、具有不同组织、不同纬丝的高经密丝织物品种进行了探讨 ,找到了解决问题的有效途径。     

精纺毛型织物经纬向剪切刚度的探讨

利用织物剪切刚度理论,在22种精纺毛型织物实验数据基础上,探讨精纺毛型织物经纬向剪切刚度与织物结构的关系,近似求得经纬向剪切刚度之间的关系方程.并将新采集的10种精纺毛型织物对方程进行验证,结果显示方程的平均误差率为8%,表明对于精纺毛型织物来说,在已知织物经向或纬向剪切刚度的条件,可以根据剪切刚度和织物经纬密的关系近似求得另一方向上的剪切刚度.     

经纬纱捻向配合对棉织物结构性能影响的探讨

探讨经纬纱捻向配合对棉织物结构性能的影响规律。在选择相同原料、相同经纬密和相同后整理方式的条件下,采用4种商业中常用织物组织织造的棉织物进行研究,每种组织分别采用经纬纱捻向相同和经纬纱捻向相反两种配合方式进行织造,通过对织物缩率、经纬密、平方米质量、抗弯刚度、断裂强力、折皱回复性等性能指标的测试发现:经纬纱捻向配置对棉织物的上述性能指标值有明显影响,而织物组织的变化带来的影响却并不明显。     

玄武岩纤维机织针织复合织物增强复合材料的弯曲性能

根据新型的机织针织复合织物的结构特点,分别选用不同线密度的高强高模玄武岩纤维作为经纱、纬纱和针织纱编织这种织物,以其作为增强体,采用VARTM工艺制作了玄武岩纤维/乙烯复合材料。为提供该新型织物增强复合材料的应用依据,测试了复合材料的横向、纵向和斜向弯曲性能,并对各个方向的弯曲载荷-挠度特征曲线及其弯曲断裂形态进行了分析。研究结果表明：这种复合材料具有较好的轴向弯曲性能,横向和纵向的弯曲性能均优于斜向,其弯曲断裂都表现一定的塑性,弯曲能量基本相近。     

The effect of yarn twist direction on the formability of woven fabrics

This experimental work examines the influence of the yarn twist on the formability of a woven fabric. Consideration is given to the phenomenon of bedding between warp and weft yarns, as affected by the local helix angles of bent yarns. A total of 28 plain weave woven fabrics (four groups, each with seven samples) were produced, using Solospun? yarns as warp and weft threads. The fabric bending length and the initial modulus of each sample were measured from which the formability was calculated. Results indicated that the fabrics in which the warp and weft twists are unidirectional (Z &; Z) have higher formability in comparison to those fabrics in which the warp and weft twists are opposite to each other (Z &; S). In addition, among the former fabrics the highest formability belongs to those in which the total helix angle of the warp and weft is close to 90 degree whereas the lowest formability belongs to the latter fabrics with least amount of twist.     

高紧度形状记忆纤维/棉机织物的记忆性能

为探究高紧度状态下形状记忆机织物的记忆性能,设计开发了15种形状记忆纤维（SMF）在经纬向呈不同分布的高紧度形状记忆纤维/棉机织物,与参照织物一起进行形状记忆性能的测试,结果表明：织物的形变固定率（Rf）一致性程度较高;形状回复率（Rr）总体随SMF含量提高有增大趋势,此规律经向比纬向明显;织物某一向的紧度超过一定限度时,经纬纱之间的摩擦阻力将会造成另一向的形状回复性能不足;单向含SMF织物因拉伸载荷对另一向的收缩和剪切效应,使得织物另一向也具有一定的形状记忆性能;高紧度机织物在某一向SMF含量固定（或不含SMF）时,织物另一向的形状记忆性能随SMF含量增加而提高。     

影响真丝织物悬垂性及耐磨性因素的分析

通过对6种真丝织物的基本结构参数及悬垂系数和磨损量的测试,应用灰色关联分析方法对织物基本结构参数与悬垂性、耐磨性能之间的关系进行定性和定量的分析.实验结果表明:真丝织物的平方米重、纬密、经纱纤度、厚度、纬纱纤度、经密对悬垂性能的影响依次减小,而对耐磨性能的影响大小依次是纬密、纬纱纤度、经纱纤度、平方米重、经密、厚度.     

蜂巢棉织物力学性能的测试与分析

为使蜂巢组织类织物在增强复合材料中得到更合理的应用,采用相同的原料和经纬密度织制不同蜂巢类组织织物,并对织物的拉伸强度、撕裂强度和顶破强度进行测试,分析不同蜂巢组织对其织物力学性能的影响。结果表明:在织物原料和经纬密度相同的情况下,不同蜂巢组织的织物其力学性能有明显的不同;纱线的交织次数越多,蜂窝越小,织物的断裂强力越大;而织物断裂伸长率、撕裂强力和顶破强力随着蜂窝尺寸的变小,先增加后减少。     

Analysis and tensile characterization of flocked fabric after rubbing

In this study, the tensile properties of flocked fabric after rubbing were studied. A statistical method was used to analyze the generated data. For this purpose, woven fabric was used as a substrate and an acrylic adhesive was applied on this substrate to hold the polyamide flock fibers forming flocked fabrics. A rubbing test was applied in dry and wet forms to the flocked fabrics before and after washing. The tensile properties of these rubbed flocked fabrics were determined. The regression models developed in this study explain the relationship between rubbing and the tensile strength of the flocked fabrics. The results from this experiment could be used in the development of flocked fabric as seat covers for the automotive industry. The warp tensile strength of a flocked fabric is generally higher than its weft tensile strength due to its higher substrate density in the warp direction. Also, the weft tensile elongation of a flocked fabric is generally higher than its warp tensile elongation due to its higher crimp ratio in the weft direction. When the stroke number increases, the warp and weft directional tensile strength and the elongation of a flocked fabric generally decrease. In addition, the stroke number of a flocked fabric before and after washing is low in its wet form compared to the dry form. The main reason is that the acrylic adhesive has poor wet properties. Results from the regression models were compared with the measured values. It was concluded that the method used in this study could be a viable and reliable tool.     

镀银纤维功能性织物的性能分析与优化设计

探究镀银纤维试制功能性纺织品的设计要点.选择锦纶基镀银纤维、棉纤维、涤纶纤维、锦纶纤维等多种材料,通过对经纬纱线的线密度、捻度、捻向、纤维成分、颜色及织物经纬密度、组织等进行系统设计,试制出了10种织物,并测试了这10种织物的防静电、导电、电磁屏蔽和防紫外线性能.测试结果表明,所试制的织物均具有良好的防静电性、导电性和电磁屏蔽性.指出,锦纶基镀银纤维织物的防静电、防紫外线、电磁屏蔽性能优良;对于防紫外线、电磁屏蔽性能而言,股线织物优于单纱织物,轻薄型织物优于中厚型织物,深色织物优于浅色织物.