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1.
The physical and mechanical characteristics of hollow polyester fibres were compared with solid polyester fibres in order
to establish their processing behaviour and performance characteristics. The effects of hollow fibres on fabric properties
were investigated by using microscopy and tests of tensile and bursting strength, pilling, abrasion resistance, water vapour
permeability, and handle. The results show that tensile strength of hollow polyester fibres and yarns are negatively affected
by the cavity inside the fibre. Hollow fibres also have higher stiffness and resistance to bending at relaxed state. Fabrics
made from hollow polyester/wool blends and pure wool fabrics show three distinguishable steps in pilling. During pilling,
hollow fibres break before being pulled fully out of the structure, leading to shorter protruding fibres. Microscopy studies
showed that the breakdown of hollow fibres started during entanglement by splitting along the helical lines between fibrils.
KES results showed that the friction between fibres and the fibre shape are the most important parameters that determine the
fabric low stress mechanical properties. However, in some aspects, the hollow structure of the fibre does not have a significant
effect. 相似文献
2.
The effect of scouring, bleaching and dyeing on the low stress mechanical and surface properties of wool woven fabrics was
studied. Fabric properties were measured by the KES-FB system. In general, mechanical properties of the treated fabrics are
greatly affected by scouring, moderately by dyeing and least by bleaching. 相似文献
3.
Low temperature plasma (LTP) treatment was applied to wool fabric with the use of a non-polymerizing gas, namely oxygen. After
the LTP treatment, the fabric properties including low-stress mechanical properties, air permeability and thermal properties,
were evaluated. The low-stress mechanical properties were evaluated by means of Kawabata Evaluation System Fabric (KES-F)
revealing that the tensile, shearing, bending, compression and surface properties were altered after the LTP treatment. The
changes in these properties are believed to be related closely to the inter-fiber and inter-yarn frictional force induced
by the LTP. The decrease in the air permeability of the LTP-treated wool fabric was found to be probably due to the plasma
action effect on increasing in the fabric thickness and a change in fabric surface morphology. The change in the thermal properties
of the LTP-treated wool fabric was in good agreement with the above findings and can be attributed to the amount of air trapped
between the yarns and fibers. This study suggested that the LTP treatment can influence the final properties of the wool fabric. 相似文献
4.
Bülent Öztürk 《Fibers and Polymers》2010,11(3):464-473
This research work was concerned with the evaluation of the effect of fibre content on the mechanical properties of composites.
Composites were fabricated using jute/phenol formaldehyde (PF), rockwool/PF, and jute/rockwool hybrid PF with varying fibre
loadings. Jute and rockwool fibre reinforced PF composites were fabricated with varying fibre loadings (16, 25, 34, 42, 50,
and 60 vol.%). The jute/rockwool hybrid PF composites were manufactured at various ratios of jute/rockwool fibres such as
1:0, 0.92:0.08, 0.82:0.18, 0.70:0.30, 0.54:0.46, 0.28:0.72, and 0:1. Total fibre content of the hybrid composites was 42 vol.%.
The results showed that tensile strength of the composite increased with increasing fibre content up to 42 vol.% over which
it decreased for jute and rockwool fibre reinforced PF composites. Flexural strength of the composite was noted to peak at
a fibre loading of 42 vol.% for jute/PF composites, and 34 vol.% for rockwool/PF composites. Impact strength of jute/PF composites
increased with increasing fibre loading but that of rockwool/PF composites decreased at higher (>34 vol.%) fibre loadings.
Tensile, flexural, and impact strengths of jute/PF composites were found to be higher than those of rockwool/PF composites.
The maximum hardness values were obtained 42 vol.% for jute/PF composite, and 34 vol.% for rockwool/PF composite. Further
increase in fibre loading adversely affected the hardness of both composites. For jute/rockwool hybrid PF composites, tensile
and impact strengths decreased with increasing rockwool fibre loading. The maximum flexural strength of jute/rockwool hybrid
PF composites was obtained at a 0.82:0.18 jute/rockwool fibre ratio while maximum hardness was observed at a 0.28:0.72 jute/rockwool
fibre ratio. The fractured surfaces of the composites were analysed using scanning electron microscope in order to have an
insight into the failure mechanism and fibre/matrix interface adhesion. 相似文献
5.
Three different silicone polymer systems, such as aminofunctional, epoxyfunctional, and hydrophilic epoxyfunctional silicone
polymers, were applied onto plasma pretreated wool fabric to improve the dimensional properties. The results showed that the
plasma pretreatment modified the cuticle surface of the wool fiber and increased the reactivity of wool fabric toward silicone
polymers. Felting shrinkage of plasma and silicone treated wool fabric was decreased with different level depending on the
applied polymer system. Fabric tear strength and hand were adversely affected by plasma treatment, but these properties were
favorably restored on polymer application. Therefore, it has been concluded that the combination of plasma and silicone treatments
can achieve the improved dimensional stability, and better performance properties of wool fabric. The surface smoothness appearances
of treated fabrics were measured using a new evaluation system, which showed good correspondence with the results of KES-FB4
surface tester. 相似文献
6.
In this study, normal and dichlorodicyanuric acid (DCCA)-treated wool slivers were ultrasonicated in formic acid aqueous solutions. The effect of the ultrasonication condition on the wool fiber splitting was examined and the mechanism of the splitting by ultrasonication in formic acid was elucidated. No wool fiber splitting occurred at formic acid content up to 70 %, but the fiber splitting accelerated as the formic acid content increased from 75 %. Although no fiber splitting occurred up to 450W ultrasonic power, the degree of splitting increased significantly with increasing ultrasonic power above 450W. The wool fiber splitting by ultrasonication was heterogeneous and FE-SEM observations revealed a three-step splitting process: 1) full removal of scale, 2) removal of cell membrane complex (CMC), and 3) fiber splitting. A comparison of the fiber splitting of normal and DCCA-treated wool revealed that the scale of the ultrasonication-treated wool was removed by peeling off rather than by dissolution. 相似文献
7.
Dyeing of wool with Marigold and its properties 总被引:1,自引:0,他引:1
This research work involves the dyeing of wool with Marigold as a source of yellow colour. To do this, wool yarns pre-treated
with Alum as a colorless mordant, dyed with Marigold and then treated with different percentages of ammonia solutions. The
chromaticity co-ordinates of samples measured in CIELAB system. TheL* values of all ammonia treated samples decreased and the values ofa*,b*,C* dependent on the ammonia solution. It can also indicate that the reflectance spectrum of treated samples decreases due to
ammonia treatment. The rate of vertical wicking decreases on Marigold dyed treated with ammonia. Color hue of the Marigold
dyed wool alters after washing with standard soap and ammonia after-treatment has no influence on washing fastness. The samples
dyed with Marigold and after-treated with ammonia show a lower light fastness. 相似文献
8.
Cristina Canal Ricardo Molina Enric Bertran Antonio Navarro Pilar Erra 《Fibers and Polymers》2008,9(3):293-300
Knitted wool and wool/nylon blend dyed fabrics were treated with low temperature plasma (LTP) to achieve optimum shrink-resistance
without impairing surface topography, colour or fastness to washing of the fabrics. As LTP tends to impair handle of the fabrics,
both wool and wool/nylon blend fabrics were submitted to industrial softening and/or biopolymer treatments after LTP treatment,
leading to hydrophilic wool and wool/nylon blend fabrics with improved shrink-resistance without any colour changes and good
fastness to washing. The results obtained were compared with those obtained by an industrial shrink-resist treatment. 相似文献
9.
This paper presents the results of a current study on polypropylene matrix composites processed by injection, with two different glass fiber lengths and five different volume fractions. Physical and mechanical properties were obtained, namely flexural strength, stiffness modulus and fracture toughness. The mechanical properties of the composites increased significantly with the increase of the fibers volume fraction in agreement with the Counto model. The effect of water immersion time was also analysed. Immersion in water promotes a marked decrease in mechanical properties in the early seven-ten days, and afterwards tends to stabilize. Water causes a decrease of the relative strength which increases with fiber volume fraction and reaches about 29 % and 32 % for 20 % of 4.5 mm fiber length and for 25 % of 12 mm fiber length respectively, after 28 days immersion in water. Fracture toughness increases with fiber volume fraction and is always higher for 12 mm fiber length composites than for 4.5 mm fiber length composites. 相似文献
10.
Lei Zhang Leng Han Yujun Wang Tianfu Zhao Xianxun Bao Masao Nakagaki 《Fibers and Polymers》2013,14(7):1190-1195
Spider dragline fiber is a high-performance biomaterial that has received much attention. To screen the outstanding spider dragline fibers, the mechanical properties and microstructures of dragline fibers collected from Nephia clavata, Nephia pilipes, Argiope bruennichi and Argiope amoena were investigated. It was found that the mechanical properties of spider dragline fiber were variable. Among the four different species, the larger spiders did not always extrude thicker dragline fibers and produce fibers with the maximum breaking force. The dragline fibers could sustain one to three times the body weight of the spider at a reeling speed of 20 mm/s. N. clavata dragline fiber showed a stronger breaking stress and initial modulus than that of N. pilipes, A. bruennichi and A. amoena. With an increasing reeling speed, the breaking strain decreased; the initial modulus increased in N. clavata, N. pilipes and A. bruennichi, but the breaking stress exhibited a different tendency. The results also revealed that dragline fiber of N. clavata contained the most β-sheet polypeptides and an excellent orientation of β-sheet molecular chains. 相似文献
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14.
Alessandra L. Da RózMárcia D. Zambon Antonio A.S. CurveloAntonio J.F. Carvalho 《Industrial Crops and Products》2011,33(1):152-157
Thermoplastic starch (TPS) was modified with ascorbic acid and citric acid by melt processing of native starch with glycerol as plasticizer in an intensive batch mixer at 160 °C. It was found that the molar mass decreases with acid content and processing time causing the reduction in melting temperature (Tm). As observed by the results of X-ray diffraction and DSC measurements, crystallinity was not changed by the reaction with organic acids. Tm depression with falling molar mass was interpreted on the basis of the effect of concentration of end-chain units, which act as diluents. FTIR did not show any appreciable change in starch chemical compositions, leading to the conclusion that the main changes observed were produced by the variation in molar mass of the material. We demonstrated that it is possible to decrease melt viscosity without the need for more plasticizer thus avoiding side-effects such as an increase in water affinity or relevant changes in the dynamic mechanical properties. 相似文献
15.
With the increasing demand of fabrics for special usage areas, more complex woven structures are designed and from the structural
point of view, especially the parameters which affect the comfort properties become more important. This paper reports the
effect of structural parameters of double layered woven fabrics, such as number of interlacing picks, period of interlacing
and number of weft skips on the basic comfort properties of the fabrics (thickness, air permeability and wicking properties)
produced according to Taguchi orthogonal array design. The investigated parameters were determined before and after finishing
treatment. According to the results, it is found that period of interlacing has an important effect on the thickness and air
permeability of both untreated and treated fabrics whereas in terms of drying coefficient, the effect of the investigated
parameters is not statistically important. 相似文献
16.
Apocynum venetum (AV) fibers were extracted by the combination of low (28 kHz) and high frequency (53 kHz) ultrasonic treatment
after aqueous alkali maceration. The surface impurities and cementing components between fibers in the range of 10–50 μm were
removed by low frequency ultrasound. The surface impurities in the range of 2–8 μm, as well as the residuals in the surface
depression and inner cavum of fibers were further eliminated by high frequency ultrasonic irradiation. The treatment did not
change crystal structure of cellulose I of AV fibers and could lead to a higher degree of crystallinity. Meanwhile, the examination
of mechanical properties showed that the AV fibers could be used for textile industry. It is demonstrated that the combination
of low and high frequency ultrasound after alkali treatment is simpler, more controllable and more environment-friendly and
is a promising degumming method for textile industry. 相似文献
17.
A series of shape memory polyurethane (PU) copolymers synthesized from 1,4-phenyldiisocyanate (PDI), poly(tetramethyleneglycol)
(PTMG), 1,4-butanediol (BD) as a chain extender, and glycerol as a cross-linking agent were tested for the mechanical properties
and the shape memory effect at the temperature 20 °C above melting temperature (T
m), and were compared with other PUs synthesized from 4,4′-methylene-bis-phenyldiisocyanate (MDI), PTMG, and BD. Mechanical
properties and shape memory effect were improved substantially by adopting both PDI and glycerol. Interestingly, enthalpy
of melting and T
m were not affected by the glycerol content. Vibration and shock absorption ability was investigated by measuring both loss
tan δ and storage modulus with dynamic mechanical analyzer (DMA). 相似文献
18.
In recent years, composites based on glass fiber reinforced polymer have been widely used in order to meet increasing durability and safety regulations, particularly in the power cable, automotive and plane industry. In this paper, mechanical and electrical properties of high density polyethylene (HDPE) and HDPE containing glass fiber polymer composites were investigated and compared at different temperatures. Composite materials were prepared with the hot pressing method. Tensile strength, % elongation and the modulus of elasticity (or Young’s modulus) were determined for each sample at different temperatures. In addition to this, at different temperatures τ σ and τ E have mechanical and electrical lifetime respectively, corresponding to mechanical tension (σ) and electrical strength (E), and this was investigated for each sample. As compared to the mechanical and electrical properties of neat HDPE, HDPE/0.5 % glass fiber composites have been found to have better mechanical and electrical durability. 相似文献
19.
Chithra Panchapakesan Nesli Sozer Hulya Dogan Qingrong Huang Jozef L. Kokini 《Journal of Cereal Science》2012
The phase behavior of zein films has been investigated at nano-scale using atomic force microscopy (AFM) and compared to the phase behavior of the bulk using a thermal characterization technique. The local surface properties of the films were evaluated as a function of water activity using AFM. The glass transition temperature (Tg) of zein films decreased with increasing water activity. Adhesion forces measured by the AFM force curves increased with increasing water activity. Topography of zein and zein fractions were evaluated both qualitatively and quantitatively by the use of AFM and dedicated software to calculate the surface roughness. It has been found that processing technologies (solvent casting, drop deposition and spin casting) has influence on the surface structures of films. The films which were formed by the alpha zein rich fraction were found to have highest roughness values. Sectional surface profiles revealed that α-zein films have mean roughness (Ra) of 1.808 nm and root mean square roughness (RMS) of 2.239 nm while β-zein films have mean roughness (Ra) of 1.745 nm and root mean square roughness (RMS) of 3.623 nm. The discussions conducted on the differences/similarities in the observations were based on the hydrophobic/hydrophilic properties and interactions of these zein fractions. 相似文献
20.
The prepolymer and the final polyurethane (PU) block copolymer were synthesized by reacting 4,4-methylene bis(phenylisocyanate)
with poly(tetramethylene glycol) and the prepolymer with 1,4-butanediol as a chain extender, respectively, to investigate
the relation between phase separation and it’s resulting properties. According to FT-IR data, the phase separation of hard
and soft segments in the prepolymer and the PU block copolymer grew bigger by increasing the hard segment content, and the
PU showed more dominant phase separation than the prepolymer. The heat of fusion due to soft segments decreased in both the
prepolymer and the PU by increasing the hard segment content, whereas the heat of fusion due to hard segments increased in
the PU did not appear in the prepolymers. The breaking stress and modulus of the prepolymer increased by increasing the hard
segment content, and the elongation at break decreased gradually, and the PU showed the highest breaking stress and modulus
at 58 % hard segment content. However, the best shape recovery of the PU was obtained at 47 % hard segment content due to
the existence of proper interaction among the hard segments for shape memory effect. Consequently, the mechanical properties
and shape memory effect of the PU were influenced by the degree of phase separation, depending on the incorporation of chain
extender as well as the hard segment content. 相似文献