• Carbon letters
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• 제13권4호
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• pp.191-204
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• 2012

Carbon nanotubes (CNTs) have exceptional mechanical, electrical, and thermal properties compared with those of commercialized high-performance fibers. For use in the form of fabrics that can maintain such properties, individual CNTs should be held together in fibers or made into yarns twisted out of the fibers. Typical methods that are used for such purposes include (a) surfactant-based coagulation spinning, which injects a polymeric binder between CNTs to form fibers; (b) liquid-crystalline spinning, which uses the nature of CNTs to form liquid crystals under certain conditions; (c) direct spinning, which can produce CNT fibers or yarns at the same time as synthesis by introducing a carbon source into a vertical furnace; and (d) forest spinning, which draws and twists CNTs grown vertically on a substrate. However, it is difficult for those CNT fibers to express the excellent properties of individual CNTs as they are. As solutions to this problem, post-treatment processes are under development for improving the production process of CNT fibers or enhancing their properties. This paper discusses the recent methods of fabricating CNT fibers and examines some post-treatment processes for property enhancement and their applications.

• 한국결정성장학회지
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• 제24권4호
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• pp.158-163
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• 2014

Mineral fiber, or be called mineral wool when it assembles in large amounts, is a kind of wide applied man-made material with excellent thermal and acoustic insulation properties. In this work, mineral fiber was produced via melt spinning method by using iron blast furnace slag as raw material. Two critical experimental parameters for fabrication were investigated: melt pouring temperature and rotating speed of spinning wheels. The mineral fiber produced under the condition of melt pouring temperature $1500^{\circ}C$ and spinning speed 4000 rpm, showed the smoother surface and most quality, while the others had rough surfaces or with heavy shots. In general, mineral fibers with the size in the range of $12{\sim}49{\mu}m$ in diameter and 8~130 mm in length can be fabricated by this method, and the production rate is more than 34 wt.%, which could be up to 57 wt.% at maximum.

• 한국염색가공학회지
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• 제18권3호
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• pp.10-15
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• 2006

In this research, we studied the dyeing properties of PET fibers in terms of $TiO_2$ contents, fiber strength and spinning oil which may cause barre' effect. The effect of $TiO_2$ contents in the fibers had no influence on the dye uptake. However, the reflectance(%) behaviors showed the different visual properties as $TiO_2$ contents in the fibers. The other factors could be considered as strength and spinning oil which also revealed difference on the dye exhaustion. The experimental results showed that $TiO_2$ contents within the fibers influenced reflectance(%) behaviors. Furthermore, fiber strength and spinning oil could be considered other major factors to impart the dyeing irregularity and barre' effect.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2000년도 봄 한국섬유공학회 학술발표회 논문집(Proceedings of the Korean Textile Conference)
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• pp.125-128
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• 2000

Chemical cellulose from an ascidian tunic is isolated by extraction, digestion and bleaching steps. The content of $\alpha$-cellulose was above 98 wt%, and it's DPw was about 918. A new regenerated cellulose fiber from the chemical cellulose obtained in this study was made using NMMO/water(87/13 wt%) as a solvent by dry jet-wet spinning. The effects of spinning speed and cellulose content of spinning dope on the properties were investigated.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2001년도 학술발표회 논문집(Proceedings of the Korean Textile Conference)
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• pp.277-280
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• 2001

• 한국염색가공학회지
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• 제6권4호
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• pp.34-39
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• 1994

For the purpose of obtaining high modulus PET tire cord fiber by high spinning speed, the change of initial modulus and taut tie molecules (T.T.M) fraction with the PET tire cord fibers by different spinning speed is investigated. Initial modulus decreased with increasing spinning speed but increased above spinning speed of 1500m/min. Therefore, high modulus PET tire cord fiber may be obtained above spinning speed of 3500m/min. It was found that the initial modulus of fibers depends on fraction of T.T.M.

• Fibers and Polymers
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• 제6권4호
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• pp.336-338
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• 2005

This paper investigates the influence of raw material and process parameters in spinning that affect the inter fiber cohesion in yams. An instrument has been developed for measuring the minimum twist of cohesion. With regard to the raw material parameters, the influence of different cotton fiber mixings for a given count of yarn is investigated. Also the effect of spinning to varying counts for a given cotton variety is studied. With regard to the process parameters, studies have been carried out to investigate the influence of noil extraction in comber, number of draw frame passages, draft pressure in ring frame and direction of twist. Cohesion improved with increase in the noil extraction percentage in the comber. Increase in the number of draw frame passages also improved the cohesion. Draft pressure in ring frame improved the fiber cohesion in yarn up to a pressure of $2.1kg/cm^2$. Direction of twist had no effect on the cohesion.

• Fibers and Polymers
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• 제3권1호
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• pp.18-23
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• 2002

The structure development and dynamic properties of fibers produced by high-speed spinning of P(EN-ET) random copolymers were investigated. The as-spun fibers were found to remain amorphous up to the spinning speed of 1500 m/min, and subsequent increases in speed resulted in the crystalline domains containing primarily $\alpha$ crystalline modification of PEN. The f modification was not found up to spinning speeds of 4500 m/min. On the other hand, annealing of constrained fibers spun at the 2100 m/min at 180,200, and 240^{\circ}C$ exhibited $\beta$-form crystalline structure, while the annealed fibers spun in 600-1500 m/min range exhibited dominantly $\alpha$-form. However $\beta$-form crystals disappeared above the spinning speed of 3000 m/min. With increasing spinning speeds from 600 to 4500 m/min, the storage modulus of as-spun fibers increased continuously and reached a value of about 10.4 spa at room temperature. The tan $\delta$curves showed the $\alpha$-relaxation peak at about 155-165^{\circ}C$, which is considered to correspond to the glass transition. The $\alpha$-relaxation peaks became smaller and broader, and shift to higher temperatures as the spinning speed increases, meaning that molecular mobility in the amorphous region is restricted by increased crystalline domain.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2008년도 춘계학술대회 논문집
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• pp.787-788
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• 2008

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1993년도 제1차 학술발표초록집
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• pp.35-35
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• 1993