• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.4 s.235
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• pp.512-518
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• 2005

Polymeric fibers with nanometer-scale diameters are produced by electrospinning. When the electrical forces at the surface of a polymer solution or melt overcome the surface tension then electrospinning occurs. Polycarbonate has been electrospun. Electrospun fibers are observed by scanning electron microscopy and transmission electron microscopy. The surface morphology of e-spun fiber has been studied by many variables that are involved in different polymer concentrations, solvent mixing ratios and ambient parameters. The average diameters of the electrospun fibers range from 200 nm to 4,570 nm when the PC concentration is decreasing from 15.5\;wt{\%}\;to\;25\;wt{\%}.$ The higher concentration of the polymer solution makes the fibers thicker due to preventing the fiber stretching. With respect evaporation effects, the solvent mixing ratios cause significant changes of the fiber size distribution. As a matter of fact the fiber diameter steadily increases with increasing amount of DMF until the solvent mixture is at THF:DMF ratio of 60:40.

• Korean Chemical Engineering Research
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• v.55 no.1
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• pp.68-73
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• 2017

The removal of particulate matter ranging from $0.01{\mu}m{\sim}10{\mu}m$ can be performed by using membrane filters composed of fibers. Electrospinning techniques offer the production of very thin fibers with a uniform fiber diameter over conventional techniques including template synthesis, melt-blown, phase separation, etc. Air filtration will be improved with electrospun membranes due to the open pore structures, high porosity, and large surface area of the membranes. In the present study, filtration efficiency increased with pore size decrease and fiber density increase induced by carbon nanotube and the increased CA (cellulose acetate) concentration during electrospinning process.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.24 no.2
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• pp.160-165
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• 2015

The 14k, 45k, and 70k Mw PCL have different crystallization temperatures and therefore have slightly different characteristics affecting the fiber diameter. To observe these behaviors, the fiber was produced at every step of $10^{\circ}C$ for each molecular weights and the diameter was measured. Moreover, the fiber was fabricated over the cooled ground plate to observe the change in fiber diameter in comparison to the normal ground plate. In case of molecular Mw 14k PCL, the diameter increased as the temperature increased. For Mw 45k PCL, the fiber diameter decreased as the temperature increased. As of Mw 70k PCL, the fiber diameter decreased with increasing temperature as well. When the experiment was conducted over the cooled collector plate, the data did not change significantly from the previous lexperiments.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.165-168
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• 2003

Nylon was the first commercialized synthetic fiber. It is a polyamide, derived from a diamine and dicarboxylic acid. The nylon fiber has outstanding durability and excellent physical properties such as stiffness, wear and abrasion resistance, friction coefficient and chemical resistance. Due to these properties of nylon 66, nano-sized fibers are produced by electrospinning method in this study. During the past years the nylon 66 fibers have been prepared by conventional melt spining. (omitted)

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.95-97
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• 2003

전기방사는 submicron 이하 크기의 섬유를 부직포형태인 3차원으로 적층된 웹상으로 얻을 수 있는 방법으로 최근 많은 연구가 되고 있다[1-3]. 전통적인 방사방법인 용융방사와 melt blown 방사 방법으로 제조되는 피치계 탄소섬유는 우수한 방사성을 갖는 프리커서 피치를 이용해야 하고 이러한 방법으로 제조되는 탄소섬유나 활성탄소 섬유는 주로 직경 10-15 um 내외의 것이 대부분이어서 상대적으로 직경이 크기 때문에 굽힘 강도가 낮아 압축가공이 취약하다. (중략)

• Membrane Journal
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• v.16 no.1
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• pp.1-8
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• 2006

Nanofiber is a broad phrase generally referring to a fiber with diameter less than 1 micron. Various polymers have been successfully electrospun into nanofibers in recent years. These nanofibers, due to their high surface area and porosity, have a great potential for use as filter medium, adsorption layers in protective clothing, etc. Nanofiber filters will enable new levels of filtration performance in the field of air filtration. In particular, nanofibers provide marked increases in filtration efficiency at relatively small pressure drop in permeability. Therefore, nanofiber filters could be substituted for conventional filter market due to the easy application of process and the possibility of coating to micron-sized non-woven sheets. This review is discussed on the trend of researche and development related to nanofiber filter including future marketability.