混纺比对麻涤纱线性能的影响

本文通过对不同混纺比下的麻涤混纺纱的性能测试分析得出涤纶比例必须达到一定量(40%)后,混纺纱的断裂伸长率才能随着涤纶比列的提高而逐渐改善;随着混纺比的改变,在涤纶含量为50%左右,混纺纱的断裂强力将出现一个低谷;随着涤纶含量的增加,毛羽和条干指标得以改善.     

亚麻/锦纶/莫代尔湿法混纺纱及织物的制备和性能研究

采用亚麻短麻/锦纶/Modal 3种纤维湿法混纺,织成织物进行性能测试.结果 表明,在锦纶和Modal的改善下,28 Nm的亚麻/锦纶/Modal纤维60/20/20混纺纱,相比亚麻纯纺纱断裂伸长提高47.8％,条干均匀度改善程度在20％ ～ 50％,有害毛羽降低16.7％,纱疵较少;混纺织物在保留亚麻优良的透气、透湿...     

混纺麻纱特征的实用图像表征技术——Ⅱ．麻／涤纱混合比的计算

基于已有的特征指标及组合指标，对苎麻和涤纶纤维的各特征指标进行“组合对”识别与分类及其边界确定。利用“组合对”参数二维解析边界函数划分和判定方法，实现了计算机图像处理对麻／涤混纺纱混合比的精确、有效地计算，混纺比与实际比较绝对误差在3％以下，相对误差在5％以下。研究表明本文提供的方法更具有纤维识别的直观准确性和有效性，并可实用和标准化。     

混纺麻纱特征的实用图像表征技术——Ⅰ．截面图像生成与特征指标

混纺织物的纤维组成和混纺比早在成纱时就已确定，其预先判定极为必要。本文探讨图像技术测量麻／涤混纺纱混合比的快速算法及其实用指标。该表征从麻／涤纱的有效切片、纱线截面摄像、图像小波分析去噪开始，到采用形态滤波法，解决图像局部灰度不均匀；使用分水岭法，分开粘连纤维和减少无效分割，实现图像的采集和预处理。实验结果证明，切片采样和小波除噪可达清晰采像要求；图像预处理可有效提高图像质量和分析精度。由此对纤维截面几何特征分析，得出主要特征参数为纤维当量截面积、异形系数和中腔纹。并依此参数及其组合完成对苎麻和涤纶纤维的自动识别，准确率达99．5％．     

苎麻与沟槽纤维混纺织物性能测试与分析

本文对采用纯苎麻纱作经纱及沟槽异形涤纶纤维混纺纱（交捻纱和sirofil纺纱）和其它纱线作为纬纱的不同织物试样的性能进行了测试和对比，分析了沟槽纤维混纺对织物吸湿排湿及其它性能的影响及其机理。     

苎麻与沟槽纤维混纺织物性能测试与分析

本文对采用纯苎麻纱作经纱及沟槽异形涤纶纤维混纺纱(交捻纱和sirofil纺纱)和其它纱线作为纬纱的不同织物试样的性能进行了测试和对比,分析了沟槽纤维混纺对织物吸湿排湿及其它性能的影响及其机理.     

混纺麻纱特征的实用图像表征技术--Ⅱ.麻/涤纱混合比的计算

基于已有的特征指标及组合指标,对苎麻和涤纶纤维的各特征指标进行"组合对"识别与分类及其边界确定.利用"组合对"参数二维解析边界函数划分和判定方法,实现了计算机图像处理对麻/涤混纺纱混合比的精确、有效地计算,混纺比与实际比较绝对误差在3%以下,相对误差在5%以下.研究表明本文提供的方法更具有纤维识别的直观准确性和有效性,并可实用和标准化.     

混纺麻纱特征的实用图像表征技术——II.麻/涤纱混合比的计算

基于已有的特征指标及组合指标,对苎麻和涤纶纤维的各特征指标进行“组合对”识别与分类及其边界确定。利用“组合对”参数二维解析边界函数划分和判定方法,实现了计算机图像处理对麻/涤混纺纱混合比的精确、有效地计算,混纺比与实际比较绝对误差在3%以下,相对误差在5%以下。研究表明本文提供的方法更具有纤维识别的直观准确性和有效性,并可实用和标准化。     

混纺麻纱特征的实用图像表征技术——I.截面图像生成与特征指标

混纺织物的纤维组成和混纺比早在成纱时就已确定,其预先判定极为必要。本文探讨图像技术测量麻/涤混纺纱混合比的快速算法及其实用指标。该表征从麻/涤纱的有效切片、纱线截面摄像、图像小波分析去噪开始,到采用形态滤波法,解决图像局部灰度不均匀;使用分水岭法,分开粘连纤维和减少无效分割,实现图像的采集和预处理。实验结果证明,切片采样和小波除噪可达清晰采像要求;图像预处理可有效提高图像质量和分析精度。由此对纤维截面几何特征分析,得出主要特征参数为纤维当量截面积、异形系数和中腔纹。并依此参数及其组合完成对苎麻和涤纶纤维的自动识别,准确率达99.5%.     

混纺麻纱特征的实用图像表征技术--Ⅰ.截面图像生成与特征指标

混纺织物的纤维组成和混纺比早在成纱时就已确定,其预先判定极为必要.本文探讨图像技术测量麻/涤混纺纱混合比的快速算法及其实用指标.该表征从麻/涤纱的有效切片、纱线截面摄像、图像小波分析去噪开始,到采用形态滤波法,解决图像局部灰度不均匀;使用分水岭法,分开粘连纤维和减少无效分割,实现图像的采集和预处理.实验结果证明,切片采样和小波除噪可达清晰采像要求;图像预处理可有效提高图像质量和分析精度.由此对纤维截面几何特征分析,得出主要特征参数为纤维当量截面积、异形系数和中腔纹.并依此参数及其组合完成对苎麻和涤纶纤维的自动识别,准确率达99.5%.     

Comfort and handle related properties of P/V blended air-jet textured yarn fabrics

The effect of blend percentage on comfort and handle related properties of fabrics made from polyester/viscose blended air-jet textured yarn weft were studied and the results were compared with fabrics made from polyester/viscose ring-spun yarn wefts of similar linear densities. It is observed that with increase in polyester content in the blend, the air permeability and water vapour permeability reduces whereas thermal resistance, transverse wicking and shear rigidity increases both in ring-spun yarn and textured yarn fabrics and bending rigidity increases in textured yarn fabrics. Textured yarn fabrics exhibit lower air permeability and extensibility, higher thermal resistance, relative water vapour permeability, transverse wicking values and bending rigidity as compared to the ring-spun yarn fabrics.     

The mechanism and/or prediction of the breaking elongation of polyester/viscose blended open-end rotor spun yarns

In this study, an analysis on the breaking elongation mechanism of the polyester/viscose blended open-end rotor spun yarns has been carried out. In addition, a back propagation multi layer perceptron (MLP) network and a mixture process crossed regression model with two mixture components (polyester and viscose blend ratios) and two process variables (yarn count and rotor speed) are developed to predict the breaking elongation of polyester/viscose blended open-end rotor spun yarns. Seven different blend ratios of polyester/viscose slivers are produced and these slivers are manufactured with four different rotor speed and four different yarn counts in rotor spinning machine. In conclusion, ANN and statistical model both have given satisfactory predictions; however, the predictions of ANN gave relatively more reliable results than those of statistical models. Since the prediction capacity of statistical models is also obtained as satisfactory, it can also be used for breaking elongation (%) prediction of yarns because of its simplicity and non-complex structure. In addition, it is also found in this study that yarn count, rotor speed and breaking elongation of polyester-viscose fibers and the blend ratios of these fibers in the yarn have major effects on yarn breaking elongation.     

Electromagnetic interference shielding effectiveness of SS/PET hybrid yarn incorporated woven fabrics

A detailed study of electromagnetic shielding effectiveness (EMSE) of woven fabrics made of polyester and stainless steel/polyester blended conductive yarn was presented in this research work. Fabrics with different structures were analyzed and their shielding behavior was reported under different frequencies. Shielding efficiency of fabric was analyzed by vector network analyzer in the frequency range of 300 kHz to 1.5 GHz using coaxial transmission line holder. The effects of different fabric parameters such as weft density, proportion of conductive weft yarn, proportion of stainless steel content, grid openness, weave pattern and number of fabric layers on EMSE of fabrics were studied. The EMSE of fabric was found to be increased with increase in proportion of conductive yarn in the weft way. With increase in overall stainless-steel content in the fabric, the EMSE of fabric was increased. As such weave is considered, it did not have significant effect on EMSE of fabrics. But fabric with lower openness and aperture ratio showed better conducting network, hence better shielding. With increase in number of layers of fabric and ply yarns, EMSE of fabric was increased.     

Comparative study on the effect of blend ratio on tensile properties of ring and rotor cotton-polyester blended yarns using concept of the hybrid effect

Study on the characteristics of blended ring and rotor spun yarns is a topic of major interest to the researchers. The overall properties of these blended yarns are affected by the relative proportion, properties of the components and their interactions. The main focus of this work is on comparing and analyzing effects of blend ratio on tensile properties of the yarns produced in different spinning systems using concept of hybrid effects that has not received enough attention from researchers. Various blends of cotton-polyester ring and rotor spun yarns were prepared. Tensile properties of the samples were examined as well. Interactions between cotton and polyester fibers was evaluated through predicting strength and elongation at break of the yarns using simple rule of mixtures (ROM) and hybrid model. Experimental results showed that, the effect of different blend ratios on tensile properties of the samples is different. In comparison with 100 % cotton yarn, promotion in braking strength of the ring and rotor spun samples occurred after increasing fraction of the polyester fiber to 50 and 66.5 % respectively. The prominent finding of the present work is that the trend of change in tensile properties of different yarns versus blend ratio is predictable via hybrid model and migration behavior of the constituent fibers. Coefficients representing the intensity of the interaction and migration index of the fibers were calculated and all results were discussed based on these calculated factors.     

Predicting the unevenness of polyester/viscose blended open-end rotor spun yarns using artificial neural network and statistical models

In this study, an artificial neural network (ANN) and a statistical model are developed to predict the unevenness of polyester/viscose blended open-end rotor spun yarns. Seven different blend ratios of polyester/viscose slivers are produced and these slivers are manufactured with four different rotor speed and four different yarn counts in rotor spinning machine. A back propagation multi layer perceptron (MLP) network and a mixture process crossed regression model (simplex lattice design) with two mixture components (polyester and viscose blend ratios) and two process variables (yarn count and rotor speed) are developed to predict the unevenness of polyester/viscose blended open-end rotor spun yarns. Both ANN and simplex lattice design have given satisfactory predictions, however, the predictions of statistical models gave more reliable results than ANN.     

Prediction of strength and weavability of blended spun yarns

In this paper, we report on predicting the strength of polyester/viscose spun yarns made on ring, rotor and air-jet spinning systems. A system has been developed to measure the weavability of yarns. Hamburger’s fibre bundle theory is modified to predict the strength of blended yarns from the strengths of single-fibre component yarns. The modified model predicts blended yarn strength more accurately than the original Hamburger’s model emphasizing the importance of yarn structure on blended yarn strength. The weavability of blended yarns is measured on a CTT instrument incorporating a shedding device which addresses the stresses viz., cycle extension, flex abrasion and beat up occur during weaving. The measured weavability compared well with that obtained on a commercial Sulzer Ruti Reutlingen Webtester. Yarn structure and strength and cohesion of fibres affect the strength and weavability of yarns.     

The effect of fabric balance and fabric cover on surface roughness of polyester fabrics

The effects of fabric balance and fabric cover on surface roughness values of textured polyester woven fabrics with different constructional parameters were investigated. The warp yarn properties (type, count and warp density) were kept constant while the effect of variation in weft yarn density and weave pattern were studied. Measurements were conducted on pre-treated white fabric samples and the results assessed in relation to their constructional properties. A general overview of the results showed that surface roughness values of polyester fabrics affected by fabric balance and fabric cover and the effects were related to fabric thickness, yarn densities, yarn crimp, positioning of yarns in fabric structure. A change in weave pattern from sateen to plain increased the fabric balance and fabric cover, but decreased the surface roughness. Similarly, an increase in weft density increased the fabric balance and fabric cover, but decreased surface roughness. In order to produce fabrics with smooth surface properties yarn density should be increased, yarn float lengths decreased, cover of fabrics increased and fabric balance improved.     

Effect of chemical softening of coconut fibres on structure and properties of its blended yarn with jute

Coconut fibres were subjected to chemical treatment to obtain softer and finer fibres, suitable to blend with other finer fibre like jute. The chemical softening recipe was optimized using Box-Behnken design of experiments as 40 % Na₂S, 10 % NaOH and 6 % Na₂CO₃, which notably reduced the fineness (33 %) and flexural rigidity (74 %) and improved tensile property of coconut fibre. Effect of softening of coconut fibre on its process performance was studied in high speed mechanized spinning system at different blend ratios with jute. Blending with jute assists in spinning of coconut fibre to produce yarn of 520 tex at production rate of 5-6 kg/h, as compared to 15 kg/day for hand spun 5300 tex raw coconut fibre yarn in manual system. Analysis of blended yarn structure in terms of packing density, radial distribution of fiber components (SEM) and mass irregularity were investigated. SEM shows yarns made from softened coconut fibre -jute blends are more compact than raw coconut fibre -jute blend yarns. Coconut fibres were preferentially migrated to core of the yarn. Major yarn properties viz., tensile strength, and flexural rigidity of raw and chemically softened blended yarns were compared against their finest possible 100 % coconut fibre yarn properties. Yarn made up to 50:50 chemically softened coconut fibre-jute blend showed much better spinning performance, and having superior property in terms of reduced diameter, higher compactness, strength, initial modulus and less flexural rigidity than 100 % raw, 100 % chemically softened coconut fibre rope, and raw coconut fibre-jute blend yarns.     

Predicting the air permeability of polyester/cotton blended woven fabrics

The aim of this study was to model the air permeability of polyester cotton blended woven fabrics. Fabrics of varying construction parameters i.e. yarn linear densities and thread densities were selected and tested for air permeability, fabric areal density and fabric thickness. A total of 135 different fabric constructions were tested among which 117 were allocated for development of prediction model while the remaining were utilized for its validation. Four variables were selected as input parameters on basis of statistical analysis i.e. warp yarn linear density, weft yarn linear density, ends per 25 mm and picks per 25 mm. Response surface regression was applied on the collected data set in order to develop the prediction model of the selected variables. The model showed satisfactory predictability when applied on unseen data and yielded an absolute average error of 5.1 %. The developed model can be effectively used for prediction of air permeability of the woven fabrics.     

Study on the packing density of structurally modified ring spun yarn

Fibres being the structural unit of a yarn, its nature, composition and arrangement can influence structure and properties. The performance of yarn changes with arrangement of its constituent fibres. Arrangement of fibres in a yarn being system specific, different spinning system results different arrangement of fibres causing variation in product performance. A change in the arrangement of fibres in an already formed yarn can be brought about by suitable physical and/or chemical treatment. A treatment to remove a component is expected to cause changes in final arrangement of fibres in a yarn. In the present study, polyester/PVA blended yarn was modified through dissolution of the later component. The resultant change in structural arrangement on dissolution was assessed by the change in radial packing distribution of fibres. Migration index, helped in identifying the location that was influenced more in the redistribution. In the parent yarn, PVA had a preferential tendency to predominate near the core. On dissolution of PVA, creation of open space was expected and collapsing of the structure led to a possible rearrangement of fibres and reduction in diameter of yarn. Fibre denier, blend ratio and twist factor were also found to influence packing density both in parent and modified yarn. Unlike published reports, interestingly, an increase in fibre packing density was observed on dissolution of PVA. Average packing density in parent yarn was found to lie at a yarn radius between 0.07 mm to 0.09 mm while for the modified yarn it was between 0.05 mm to 0.07 mm.