• Textile Coloration and Finishing
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• v.14 no.2
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• pp.109-109
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• 2002

A study has been made of the dry-jet-wet spinning of PAN copolymer fibers using 60% aqueous zinc chloride solution as solvent and 25∼40% aqueous zinc chloride solution as non-solvent. The technological characteristics of this method were that small streams of dope were extruded from the die and allowed to pass through a short distance of air gap(about 10mm) before entering the spinning bath for full coagulation. This work showed the importances which coagulation condition, stretch ratio and fiber tenacity up to 10.5 g/d could be obtained with elongation of 11∼16%. Individual fibers were evaluated on the basis of density and mechanical properties such as tenacity and elongation etc.

• Textile Coloration and Finishing
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• v.14 no.2
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• pp.33-39
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• 2002

A study has been made of the dry-jet-wet spinning of PAN copolymer fibers using 60% aqueous zinc chloride solution as solvent and 25∼40% aqueous zinc chloride solution as non-solvent. The technological characteristics of this method were that small streams of dope were extruded from the die and allowed to pass through a short distance of air gap(about 10mm) before entering the spinning bath for full coagulation. This work showed the importances which coagulation condition, stretch ratio and fiber tenacity up to 10.5 g/d could be obtained with elongation of 11∼16%. Individual fibers were evaluated on the basis of density and mechanical properties such as tenacity and elongation etc.

• Textile Coloration and Finishing
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• v.33 no.3
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• pp.120-130
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• 2021

The condition of covering process using thermoplastic polyetherester elastomeric fibers(TPEE) was established. Two types of core yarn(TPEE, Spandex) and one type of effect yarn(PET) were used as materials to confirm the change in physical properties of covering yarn under various covering conditions. In addition, the effects of the treatment temperature on the elongation at break of covering yarn after heat treatment was analyzed. Through this analysis, it was confirmed that the elastic recovery of TPEE which is used as the core yarn was increased with the draw ratio, but decreases when it exceeds 1:2.5. And the elongation at break of the covering yarn could be increased by increasing the twist per meter of it. Additionally, it was confirmed that the elastic recovery of TPEE which is used as a core yarn, could be increased by applying heat treatment.

• Journal of the Korean Applied Science and Technology
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• v.25 no.3
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• pp.380-387
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• 2008

The effects of the applied stretch and MgADP binding on the structure of the actin and myosin cross-bridges in rabbit fibers in the rigor state have been investigatedwith improved resolution by x-ray diffraction using synchrotron radiation. To clarify the structure of the ATP hydrolysis intermediates formed by actin and myosin cross-bridges,the effects of various phosphate analogs in the of MgADP on the structure of the thin and thick filaments in glycerinated rabbit muscle fibers in the rigor state investigated by x-ray diffraction with a short exposure time using synchrotron radiation. These results strongly suggest that when MgADP and phosphate analogs such as metallofluorides(BeF3 and AlF4)and vanadate(VO4(Vi)) were added the rigor fibers in the presence of the ATP-depletion backup system, the intensities of the actin-based layer lines were markedly weakened. We found that the intensity of the 14.5 nm-based meridional reflections increase by 20-50% when phosphate analogs such as metallofluorides(BeF3 and AlF4) and vanadate(VO4(Vi)) was added to the rigor muscle.

• The Journal of Natural Sciences
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• v.8 no.1
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• pp.145-151
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• 1995

The stretching of synthetic fibers by hot dry process is very difficult, because these fibers have high glass transition temperature at above $150^{\circ}C$. But, we used a swell-wet stretching precess; the fibers are stretched in a swelling agent such as organic solvents at lower temperature. In this study, 100% acryl fibers were uniaxially stretched with free width at $70^{\circ}C$ by swell-wet process in organic solvents. The stretchability was estimated by stretching work. This work is concerned with stretching stress and strain, and initial modulus. We found that it is a good parameter for the estimatation of high strength to the acrylic fiber. The effects of stretching conditions on the molecular orientation for high strength and mechanical properties of PAN fibers were measured.

• Fashion & Textile Research Journal
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• v.8 no.3
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• pp.357-362
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• 2006

This study is to evaluate the objective sensibility of the commercial lining fabrics. Five kinds of the linings were collected by adding taffetas with four kinds of fibers (polyester, nylon, rayon, and acetate) to one polyester stretch fabric. The six basic mechanical and hand properties were studied by using KES-FB system (Kawabata Evaluation System). The result of measuring the mechanical properties shows that polyester has high bending rigidity (B), that polyester-stretch has a high value of linearity of load-extension curve (LT), tensile energy (WT), tensile resilience (RT), and coefficient of friction (MIU) and a low value of bending rigidity(B), shear property, and geometrical roughness (SMD). The nylon has a high value of bending rigidity (B), shear property, and compression resilience (RC). The rayon has a high value of coefficient of friction (MIU) and linearity of compression-thickness curve (LC) and a low value of shear property, and the acetate has a low value of shear property. The result of hand value shows that polyester, nylon, and acetate are a high value of KOSHI (stiffness), NUMERI (smoothness), and FUKURAM (fullness & softness), and they feel stiff and massive, that rayon has a low value of NUMERI and FUKURAMI. The total result of hand value shows that polyester taffeta and polyester stretch fabric are about the same as the best material for the lining of a woman's dress for spring and summer, and the next thing is acetate, but nylon and rayon are somewhat inferior materials. This provides a fundamental data for the comfortable clothing production of a higher value-added product through the study on the mechanical and hand properties of the lining as well as the right side of fabrics.

• Journal of Fashion Business
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• v.8 no.5
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• pp.115-124
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• 2004

PTT(polytrimethylene terephthalate) is a thermoplastic that can be melt-spun into fibers and has extensive applications in carpets, textiles and apparel, engineering thermoplastics, nonwovens, and films or sheets. This polymer combines the good properties of nylon and polyester. Compared with other synthetic fibers such as nylon and acrylic, the PTT fibers feel softer, dye easier with vibrant colors, stretch and recover better. Moreover, the PTT fibers for carpets resist most stainings, clean better, and dry faster. The PTT was first patented in 1941, but it was not until the 1990's, when Shell Chemicals developed the practical method of producing PDO, the raw material for PTT. Many studies have been done including the retention of carpet texture using an image analysis technique, or compressional resilience of the carpet for long term use. In this study, PTT and nylon BCF carpets were compared in terms of the compressional properties including the resilience, using one of the KES system for repetitive measurements. The compression resilience(RC) values of the PTT BCF carpets far exceed those of nylon 6 BCF carpets. The RC values of the PTT BCF carpet(cut) specimens are $42{\sim}45%$ for 5 successive compression deformations, while those of the nylon BCF carpet specimens(cut) are $26{\sim}28%$. There is also a similar trend in the RC values for the other type of carpet which is the loop type. This resilience is one of the important factors of carpet usage evaluation.

• Fashion & Textile Research Journal
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• v.20 no.1
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• pp.93-100
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• 2018

This study comparatively analyzed the changes in the dimensional stability and the mechanical properties of stretch knit fabrics associated with washings conditions in order to determine the most appropriate washing method. Polyester and spandex knit fabrics were washed 25 cycles with nine washing condition profiles that controled detergent, hardness. temperature and RPM. The knit fabrics with repeated washings were evaluated by dimensional stability and measured by the KES-FB system. Polyester and spandex fibers have good chemical resistance. However, the changes in the dimensional stability and the mechanical properties were observed in washed knit fabrics. After repeated washings, the knit fabrics washed in an alkali or neutral detergent had good dimensional stability compared with the knit fabric washed in functional detergent. The washed knit fabrics were extended, stiff, rough, and had a smaller volume. The changes were the result of the rearrange of polyester fibers which twisted around spandex core and chemical interactions involving the detergent and the physical and mechanical forces of washing. Especially, using an alkali detergent resulted in increased stiffness and roughness of the knit fabric. In conclusion, the washing in water with low hardness and a neutral detergent can minimize the changes in dimensional stability and mechanical properties of polyester and spandex knit fabric.

• Fibers and Polymers
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• v.1 no.1
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• pp.25-31
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• 2000

Poly(3-hexyl thiophene)(P3HT) and poly(3-dodecyl thiophene)(P3DT) were polymerized by oxidative coupling with ferric chloride. The P3HT light-emitting device emitted red light and it could be observable in the ordinary indoor light. The device had the turn-on electric field of about 3$\times$$10^7$ V/m. The maximum electroluminescene (EL) intensity was obtained when the thickness of polymer layer was about 130 nm in IT0/P3HT/Al device. The maximum external quantum yield was 0.002%. The maximum luminance was 21 cd/$m^2$. The EL intensity decreases with increasing the crystallinity of the polymer layer. By using the oriented poly(3-alkyl thiophene)(PAT) layer as an electroluminescent layer in the ITO/polymer/Al light-emitting devices, the polarized EL light emission was observed. The EL intensity ratio of parallel to perpendicular direction to the stretch direction for P3HT was about 1.40.

• International Journal of Aeronautical and Space Sciences
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• v.11 no.4
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• pp.360-365
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• 2010

Three phase composite materials are widely used in the shipbuilding industry. When reinforced with fiber and particle, the physical and mechanical properties of polymer composite materials are improved. This paper presents the bending analysis of a three phase composite plate with an epoxy matrix, reinforced glass fiber and titanium oxide particles including creep effect when shear stress is taken into account. The obtained results indicate that creep strains lead to compression in the composite material. Introducing reinforced fibers and particles reduces the plate's deflection, when increasing the stretch coefficient allows the calculation of creep deflection during a long loading period.