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1.
PET yarns textured at different texturing conditions were treated with superheated steam or dry heat at different temperatures
for different times. The effects of the treatment conditions on the thermomechanical and structural changes of the yarn were
examined by shrinkage, X-ray diffraction and birefringence measurements. With increase in superheated steam temperature, the
crystalline orientation factor and birefringence decreased, whereas crystal size increased. Dry heat treatment had a smaller
effect on shrinkage and structural properties in comparison with superheated steam treatment. The additional shrinkage after
texturing process was investigated. The effect of heat-setting in both media was more significant at 200 °C. The time dependence
of the properties was not linear. 相似文献
2.
In the present study, effect of OPP (oxidized PP) fraction on the mechanical and structural properties of produced fibers
is investigated. Polypropylene powder without antioxidant materials was oxidized at the suitable thermal condition. The various
fractions of OPP were blended with PP in the chips shape, and employed as starting material in a melt spinning machine for
production of filament yarn. Then as-spun filaments were drawn and finally textured. Structural properties including density,
birefringence and FTIR and physical properties consisting of shrinkage, tensile properties and crimp properties were measured.
Results show that blending of OPP with virgin PP reduces tacticity and crystallinity, but it hasn’t any effect on orientation.
Physical properties of drawn yarns and textured yarns were reduced with increasing of OPP fraction. Moreover, increasing of
OPP fraction in blend, reduce crimp properties of textured yarn. 相似文献
3.
Different polyolefines (low density polyethylene (LDPE), linear low density polyethylene (LLDPE), high density polyethylene
(HDPE) and isotactic polypropylene (iPP)) were oriented via solid-state stretching at an elevated temperature. In order to
investigate orientation-induced changes in microstructure and crystallinity, optical microscopy (OM), scanning electron microscopy
(SEM), wide angle X-ray scattering (WAXS) and differential scanning calorimetry (DSC) were employed. To quantify the degree
of molecular orientation WAXS data were used to calculate Herman’s orientation function (f
c
); the results reinforce the morphological picture obtained from OM and SEM confirming Peterlin’s molecular model of drawing.
Furthermore, orientation-induced changes in the crystalline phase, especially in its volume and perfection, were observed
by DSC and WAXS. Comparison between these data showed that the biggest change in the degree of crystallinity was achieved
during the transformation of the initial lamellar into fibrillar structure. After completion of this transformation further
orientation, which occurs through plastic deformation of fibre structure, introduces only minor changes in crystallinity.
The overall orientation-induced behaviour hasn’t been considerably influenced by the structural differences amongst polyolefins. 相似文献
4.
Raju Seenivasan Rengasamy Raghavendran Guruprasad Patnaik Asis 《Fibers and Polymers》2005,6(2):146-150
In this paper, friction of air-jet textured yarns is investigated. Using a friction measuring apparatus fabricated in-house,
dynamic friction forces of the yarns under yarn-to-metal (YM) and yarn-to-yarn (YY) rubbing modes are measured. The influence
of processing variables of air-jet texturing viz., overfeed, air pressure, dry/wet texturing and normal/core-and-effect texturing
on dynamic friction is analysed. The results indicate that friction force increases with increasing rubbing speeds and yarn
input tension. YM dynamic friction decreases initially and then starts to increase at higher overfeeds. YY dynamic friction
increases with increasing overfeed. YM dynamic friction decreases with an increase in air pressure while an opposite trend
is observed for YY friction. Wet textured yarns have higher friction than dry textured yarns. Core wetted core-and-effect
textured yarns have higher friction than normal textured yarns. 相似文献
5.
Delamination is the most common failure mode in laminated composites, due to the reduced strength in the through-the-thickness direction. This paper describes the development of core-and-effect textured glass yarns for improving the bonding strength of laminated glass woven fabric composites. Air-jet texturing introduces bulk and loops in the yarn which provides more contact surface between the fibers and the resin. However, the yarn tenacity decreases after texturing because of the reduced alignment of the filaments. The effects of texturing air pressure, yarn overfeed ratio, yarn linear density and core-sheath ratio were studied in this paper. The tenacity of glass yarns decreased significantly after the texturing process. The reduction was smaller for yarns with a higher core linear density. The effects of texturing air pressure on the tenacity were found to be insignificant. 相似文献
6.
Delamination is the most common failure mode in laminated composites due to the reduced strength in the through-the-thickness direction. Air-jet texturing was used to provide more surface contact between the fibres and the resin by producing bulk and loops in the yarn. The development and characterization of core-and-effect textured glass yarns and the effect of texturing on the mechanical properties of laminated composites were presented in the previous papers. This paper describes the effect of texturing on the inter-laminar fracture toughness (Mode I) of glass laminated composites. The composites of twill weave fabrics were developed from both the textured and non-textured yarn and fracture toughness is tested in warp and weft directions. Significant improvement was observed in the Mode I fracture toughness of the composites after texturing. The bulkier, loopy structure of the textured yarn provided more surface contact between the fibre and the resin and significantly improved the bonding strength. 相似文献
7.
The length and fineness of fibers are critical to the strength of yarns. Much research has been conducted on the issue in
the past decades. Zeidman and Sawhney introduced a new parameter called strength efficiency (SE) of fibers in a yarn using
an elaborate probabilistic method. Their final formula, a non-dimensional measure, describes the influence of the fiber length
distribution on the strength of yarn. The result, however, is based on the assumption that the fibers are identical in all
respects including their cross-sectional area. The influence of fiber fineness can not be seen in their formula. In fact the
joint influence of fiber length and fineness is rarely studied. We derive a new strength efficiency of the joint influence
of fiber length and fineness on the basis of Zeidman’s result. The conclusion is helpful to the understanding of the comprehensive
influence of fiber length and fineness on the strength of yarn. Furthermore, we give a plausible method to estimate the critical
length defined by Zeidman. The result can be applied to the research of the properties between fibers and yarns. 相似文献
8.
In present work, PET FDY has been used to blend with diacetate filaments by air texturing process and core-and-effect air-textured
yarns have been produced. The influences of both over-feeds of core and effect components on properties of textured yarns
were mainly examined. It was observed that a spun-like effect of diacetate filaments occurred during air texturing and there
were a little amount of free fiber ends besides loops on blended air textured yarns, while the number of free fiber ends changed
little with variation in over-feeds. The tenacity of textured yarns decreased with increase in over-feeds of effect or core
component. The breaking elongation increased with increase in over-feed of effect component, but decreased with increase in
over-feed of core component. The yarn stability improves when both over-feeds are increased. The effect of over-feeds on boiling
water shrinkage shows no clear trend. The core and average diameters are higher at high over-feed of effect component, but
the over-feed of core component exhibits little effect on yarn diameters. The number and size of loops are increase with increased
over-feed of effect component. 相似文献
9.
Polyvinyl chloride (PVC) fibers were melt-spun to prepare mono and multifilament yarns. To find optimum spinning and drawing
conditions, various parameters such as spinning temperature, spinneret diameter, drawing temperature, and drawing ratio were
examined. From the observation of the spinnability under various conditions, we found that the optimum conditions were as
following: the extrusion temperature and die temperature were 175–180°C and 185–190°C, and the drawing temperature and drawing
ratio were 85–95°C and 3.4, respectively. Under these conditions, the spinneret diameter could be reduced to the minimum value,
0.5 mm. Spun PVC filament yarns were subjected to the different yarn texturing process of stuffing box and pin false-twist
method. The PVC yarn fabric was prepared by the knitting of textured yarns. Finally, the anion-emission and antibiotic properties
of the knitted PVC fabrics were precisely evaluated. 相似文献
10.
Composite materials have a wide range of applications in structural components because of their high strength-to-weight and stiffness-to-weight ratios. However, the most crucial and common life-restricting crack growth mode in laminated composites i.e. delamination is of great concern. Air jet texturing was selected to provide a small amount of bulk to the glass yarn. The purpose was to provide more surface contact between the fibres and resin and also to increase the adhesion between the neighbouring layers. These were expected to enhance the resistance to delamination in the woven glass composites. The development and characterisation of core-and-effect textured glass yarns was presented in the previous paper. This paper describes the comparison of the mechanical properties of composites produced from air-textured glass yarns and the composites made from locally manufactured carbon fabrics. The tensile, flexure and inter-laminar shear strength (ILSS) were compared and it was observed that although glass fibres are inferior to carbon fibres in terms of mechanical properties however, the flexure strength and ILSS of glass based composites increases after texturing and were found closer to the properties of carbon based composites. 相似文献
11.
In this research, possibility of producing and processing antibacterial organic/inorganic nanocomposite polypropylene filament
yarns for permanent antimicrobial efficiency has been investigated. First PP powder and inorganic nanocomposite filler were
mixed in a twin screw extruder and modified masterbatch was produced. Continuous filament yarn was made by a pilot plant melt
spinning machine from the blend of PP granule and various blending contents of the prepared masterbatch. Pure PP and all other
combined samples showed acceptable spinnability at the spinning temperature of 240 °C and take-up speed of 2000 m/min. After
producing as-spun filament yarns, samples were drawn, textured and finally weft knitted. Physical and structural properties
of as-spun and drawn yarns with constant and variable draw ratios were investigated and also tensile and crimp properties
of textured yarns were evaluated. Moreover, the DSC, SEM, FTIR techniques have been used for characterization of samples.
Finally antibacterial efficiency of knitted samples was evaluated. The experimental results indicated that the maximum crystallinity
reduction of modified drawn yarns has reached to 5 %. The observed improvement in the tensile properties of modified as-spun
yarns compared to the pure PP was significant. Drawing process improved generally the tensile properties of as-spun yarns.
Tensile properties of modified textured and drawn yarns were higher than the pure PP. An optimum of antibacterial activity
has been observed in the sample containing 0.75 wt% of nano-filler. It is interesting that the optimum of tensile properties
has been also obtained for the sample with maximum bioactivity. 相似文献
12.
Influences of processing parameters on tensile property, stability and bulk of core-and-effect air textured yarns of diacetate
and polyester filaments are mainly examined in this paper. When the air pressure is raised, the tenacity and breaking elongation
of textured yarns are reduced, Instability I and II tend to decrease at first and then increase, the core bulk declines markedly
at first and then changes slowly, whereas the overall bulk changes little at first and then goes up greatly. With increase
in texturing speed, the yarn tenacity and breaking elongation both drop initially then begin to increase, the core bulk and
overall bulk are almost linearly increased, while the yarn instability changes with an unclear trend. When the winding underfeed
ratio is increased, the yarn tenacity, breaking elongation and core bulk are reduced, but the yarn stability is slightly improved.
The wetting of the core component produces higher tenacity, breaking elongation, instability and bulk, compared with that
of the effect component or that of both, but the difference is insignificant. 相似文献
13.
Polylactic acid (PLA) is a biodegradable and compostable polymer obtained from annually renewable resources and is acknowledged to be sustainable and non-polluting polymer with substantial commercial prospective as a textile fiber however, there is lack of literature on apparel applications of this polymer. Therefore in this study it was aimed to develop biobased compostable gloves from PLA draw textured melt spun yarns and to examine the effect of yarn linear density, fabric structure and stitch density on thermo-physiological comfort and moisture management properties of PLA based gloves. 100 % PLA based multifilament yarns of two different linear densities were melt spun and later draw textured on false twist texturing machine to be used for gloves knitting. Single jersey and rib structures were produced with two different stitch densities to investigate their effect on thermal conductivity, thermal resistance, relative water vapour permeability, air permeability and moisture management properties of the gloves. Minitab statistical software was employed to analyze the results of test samples. The coefficients of determinations (R2 values) presented good estimation capability of the established regression models. The outcomes of this research may be useful in determining suitable manufacturing requirements of PLA based gloves to accomplish precise thermo-physiological and moisture management properties. 相似文献
14.
This paper is aiming to develop high shrinkable differential shrinkage and mixed fibre nylon composite yarns by applying the
high shrinkable polyester manufacturing technology. The wet and dry thermal shrinkages and mechanical properties of developed
nylon composite yarns are measured and discussed with processing factors in the spinning and texturing processes. And the
effects of the processing factors on the physical properties of high shrinkable nylon composite yarns are investigated. For
this purpose, twenty seven nylon 30d/12f SDY were prepared with variation of spinning temperature, 2nd godet roller temperature
and draw ratio on the spinning machine. The optimum spinning condition which showed maximum wet thermal shrinkage and stress
was determined and high shrinkable nylon 30d/12f SDY spun under this optimum condition used as a core and three kinds of regular
nylon filaments used as sheath were processed on the texturing machine with variation of 1st and 2nd heater temperatures.
The optimum texturing process condition was decided through analysis of dry thermal shrinkage of these core and sheath nylon
filaments. Finally, high shrinkable differential shrinkage and mixed fibre nylon composite yarns were made under the optimum
texturing condition on the texturing machine, its wet thermal shrinkage was 13.8 %, which was much more higher than that of
regular nylon composite yarns. The differential shrinkage effect of the developed nylon composite yarns was found in the yarn
surface and cross section profiles by microscope and SEM. 相似文献
15.
Manufacture technique and electrical properties evaluation of bamboo charcoal polyester/stainless steel complex yarn and knitted fabrics 总被引：1，自引：0，他引：1
Jia-Horng Lin An-Pang Chen Chin-Mei Lin Ching-Wen Lin Chien-Teng Hsieh Ching-Wen Lou 《Fibers and Polymers》2010,11(6):856-860
There are derivative problems of electromagnetic wave radiation accompanying the advances of science and technology nowadays
and secure protections are also emphasized gradually. To shield these electromagnetic wave radition jeopardizing people’s
health, in this study, stainless steel wires were the core yarn and bamboo charcoal polyester textured yarns were the wrapped
yarn. The bamboo charcoal polyester/stainless steel (BC/SS) complex yarns were manufactured using a rotor twister machine.
The BC/SS complex knitted fabrics were woven with the complex yarns employing a circular knitting machine. Three manufacture
parameters were the wrapped amount of the complex yarn (2 to 6 turns/cm), the lamination amount of the knitted fabrics (1
to 6 layers) and lamination angles of the knitted fabrics (0°/0°/0°/0°/0°/0°, 0°/45°/90°/−45°/0°/45°, and 0°/90°/0°/90°/0°/90°).
The knitted fabric exhibited the lowest surface resistance 32.3 Ω/sq. Optimum electromagnetic shielding effectiveness (EMSE)
was 45 dB when the knitted fabrics were with 0°/45°/90°/−45°/0°/45° laminating in 0.51 GHz. 相似文献
16.
Blending of nylon filament with viscose can overcome the drawbacks of these yarns. Thermoplastic and thermoset filament yarns
can be blended in air-jet texturising method. The characteristics of nylon/viscose blended filament yarns are required to
be understood in order to convert them in to useful products. Therefore, nylon/viscose blended yarns in different proportions
were produced using nylon 6 and viscose filament yarns in air jet texturising machine. The textured yarns were also produced
in dry and pre-wet conditions to understand the effect of water on textured yarn characteristics. It was found that the loops
frequency, bulkiness of nylon/viscose blended textured yarns increase with increase in viscose proportion. The Loops stability,
tenacity and breaking elongation decrease with increase in viscose proportion. Pre-wet textured yarn show higher loops, bulkiness,
and good loop stability than their corresponding dry textured yarns. 相似文献
17.
Snezana B. Stankovic 《Fibers and Polymers》2008,9(2):187-193
The novel designed hemp/filament hybrid yarns were used to produce knitted fabrics in order to investigate the influence of
the unique internal structure of hybrid yarns on compressional behavior of clothing textile materials. The knitted fabrics
are subjected to successive compression-release cycles and the compression-release curves obtained made it possible to calculate
the particular compression parameters such as recoverable and irrecoverable compression. By using the parameters the non-elastic
deformation components (viscoelastic and plastic deformation) are determined. In spite of generally accepted fact that van
Wyk’s theory has some limitations, since it does not explain the hysteresis caused by fiber slippage and friction effects,
the two-parameter mechanical model derived from van Wyk’s compression theory is applied successfully to determine the compression
hysteresis. 相似文献
18.
The tensile properties of spun yarns decisively influence its performance in various mechanical processing stages. This study
is primarily aimed at simultaneous analysis of two tensile properties of spun yarns namely tenacity and breaking strain, which
play crucial role in determining the frequency of warping breaks. The threshold values of yarn tenacity and breaking strain
required for 20’s Ne carded cotton yarn to sustain the imposed stresses and strains during warping process have been determined
using a bivariate normal distribution model. This study opens up the possibility of minimizing end breakage rate in various
manufacturing processes of textile industry by engineering of spun yarns devoid of potential weak spots which are responsible
for breaks. 相似文献
19.
This research deals with the investigating the effect of nanoparticles on the various properties of nanocomposite fabrics produced from melt spinning of various blend ratios of prepared masterbatch containing Ag/TiO2 nanoparticles. The results revealed that the wear properties of modified fabrics improved as compared to pure fabrics with a trend justified considering modulus or crystallinity of fabrics with opposite effects. About 40 % UV protection enhancement has been obtained applying this kind of nanoparticles in the close relationship with the crimp contraction of textured yarns. A considerable improvement in the garment comfort has been recorded for nanocomposite sample containing 1 wt% nanoparticles. The lower permeability at low environment temperature and a higher at higher one, as compared to the pure sample, were obtained using this sample. It is highly interesting that these desirable changes in permeability can be achieved in the range of common environment temperatures (15–35 °C) being adapted to the human body requirements. The changing point is about 25 °C exactly meeting the body requirements by changing environment temperatures. A UV-induced solid state nanocomposite interaction increasing wear properties of UV-irradiated nanocomposite fabrics has been discovered. 相似文献
20.
从国家苎麻种质长沙苎麻圃中选择有代表性的55个苎麻品种为材料．用X射线衍射法测定苎麻精干麻的结晶度。用面积法计算各个品种的结晶度,分析苎麻纤维结晶度及其与主要纤维品质性状的相关性。研究结果如下：苎麻品种问纤维结晶度有显著性差异。55个苎麻品种纤维结晶度平均值变幅在69％-73％之间,变异系数为0．9769％,纤维结晶度最低是川苎二号。其值为69．03％,最高是印尼麻,其值为72．31％。同一品种的不同季别的苎麻纤维结晶度有一定的差异。二麻结晶度最低,与头麻、三麻之间有显著性差异;同一品种苎麻不同收获期、不同部位纤维结晶度有差异。品种中苎一号、圆叶青和NC01在1／3黑杆时期的纤维结晶度与1／3黑杆前的纤维结晶度有显著性差异,1/3黑杆前收获可显著降低结晶度,但是会降低苎麻的产量：1／2黑杆时期后的结晶度值无显著性差异,结晶度值趋于稳定;苎麻纤维结晶度与断裂强力呈极显著负相关。相关系数为-0．39526＊＊（n=55）;苎麻纤维结晶度与纤维细度呈显著正相关,相关系数为O．31363＊（n=55）。 相似文献