• Textile Coloration and Finishing
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• v.34 no.1
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• pp.27-37
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• 2022

In this study, a study and interpretation of the spinning process in copolymerized aramid spinning was conducted. In order to proceed with the spinning process modeling and analysis, the spinning process was modeled through the physical property modeling of the spinning solution and the structural modeling of the spinneret, and structural stability and flow of the spinneret for this spinning were analyzed. After modeling the spinning solution and the spinneret in a virtual space, the pack pressure and flow rate when the spinning solution was discharged were simulated. Macroscopically, the structural stability of the spinneret was confirmed at the standard pack pressure (100 kg·f/cm²), and microscopically, the flow rate and pressure drop data of the spinning solution according to the L/D(Length (L)/Diameter (D)) value were analyzed. Based on the research and development of virtual engineering modeling and analysis, we present the possibility of changing the shape and mechanical properties of copolymer aramid fibers according to the spinning process.

• Proceedings of the Membrane Society of Korea Conference
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• 1995.10a
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• pp.5-9
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• 1995

In the dry-jet-wet-spinning process of a hollow fiber membrane, the polymer solution is pumped into a coaxial tube, jet spinneret. The threadline emerging from the spinneret is stabilized by an internal coagulating medium(liquid or gas) as it emerges from the jet orifice. The nascent hollow thread is further stabilized in a quench bath as shown in Fig. 1. In this scheme, three mechanism of formatiota(temperature gradient, solvent evaporation, and solvent-nonsotvent exchange) can be combined. The changes which promote stabilization often play a dominant role in determining the ultimate fiber wall structure as well. Hence, in pratice, hollow fiber stabilization and development of membrane structure are commonly inseparable. However, fiber dimension(the inside diameter and wall thickness of the hollow fiber) is mainly a rheological problem and is determined by dope pumping rate, spinneret diatance from the coagulation bath, inner coagulant flow rate, and fiber draw-rate. Besides rheological phenomena play a prominent part in the final properties of the hollow fiber.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10a
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• pp.73-74
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• 2003

Silkworms construct cocoons that are strong and resilient structure by their masterful behavior. Knowing the essentials of their skill, we could apply them to building many types of objects. In this research we focused on the some properties of silkworm′s spinneret and body position in their cocoon construction process. Silkworm′s spinning process was measured by two Video camera system and then analyzed to find out some appropriate statistical models representing the behavior. Furthermore, we interested in the locus pattern of spinneret based on "8" and "S" character. We modeled this pattern to the Lemniscate′s curve function, and tried to make a design of plane surface.

• Fashion & Textile Research Journal
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• v.14 no.3
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• pp.472-477
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• 2012

The conditions of wet spinning were considered in order to prepare the fine denier of acrylic fiber. Polyacrylonitrile copolymer was synthesized by the copolymerization of acrylonitrile (AN) and methyl acrylate (MA) initiated by an aqueous sulfite-chlorate redox system. Acrylic fiber was manufactured through wet-spinning in a dimethyl formamide (DMF) system. The conditions of wet-spinning were investigated by i-value, spinning speed, diameter of spinneret, draw ratio, water content of spinning dope and morphology of protofiber. The physical properties of fibers were investigated by Instron. In this experiment, the minimum i-value decreased with the decreasing spinneret diameter, an increased spinning speed, and an increased coagulation bath (CBC) concentration. The maximum draw ratio increased with an increased CBC. The optimum CBC and water content of the spinning dope were 60%-65% and 3.5%, respectively. The tenacity at the breaking point increased with a decreased fineness of fiber. The elongation at breaking point was almost the same value as a function of the fineness of fiber.

• The Korean Journal of Soil Zoology
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• v.7 no.1_2
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• pp.51-57
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• 2002

Two new and two known species of mononchid nematodes from Korea are described and illustrated. lotonchus cucumis sp. n. is characterized by 2.9-3.2 ㎜ long body, presence of 3 each pre- and post-vulval papillae, vagina with cuticularized pieces, a long tail with terminal spinneret. Mylonchulus unicus sp. n. has 1.1-1.2 ㎜ long body, and is characterized by having 2 pairs of teeth on subventral walls of buccal cavity; submedian denticles arranged in 2-3 rows, very short post-vulval sac and terminal spinneret. Mononchus sinensis Soni and Nama (1983) and Mononchus aquaticus Coetzee (1968) are reported for the first time from Korea.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.273-276
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• 2002

The fiber formation of conventional melt spinning is extruded by forcing the polymer melt through a spinneret by pumping mechanism usually involving high pressure. This is followed by cooling, solidification and appropriate drawing of the fiber. The spinning process is broadly applicable to polyolefin, polyamide, polyester and indeed the whole range of fibers forming thermoplastic polymers. (omitted)

• Proceedings of the Membrane Society of Korea Conference
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• 1994.04a
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• pp.34-35
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• 1994

Tube-in-orifice형태의 spinneret을 제작하여, polyethersulfone을 재질로 하는 capillary membrane을 건습식방사공정을 통해 제조하였다. 기공형성계는 PVP를, 용매는 NMP/DCM을, 내부응고제는 물과 NMP의 혼합물을, 외부응고제는 냉각수를 사용하였다. 내부응고제의 NMP농도에 따른 막의 형태와 microstructure를 연구하였다. 내부응고제가 약한 응고력을 가질 때 macrovoid가 없고, 내부의 활성층이 치밀한 막을 얻을 수 있었다. PES-NMP/DCM-PVP조성(25-44/11-20)의 용액으로, 40% NMP수용액을 내부응고제로 사용하여, 막을 제조하고 이를 모듈화하여, 한외여과실험을 한 결과, MWCO 8,000인 모듈이 얻어졌으며, 이 모듈의 Flux는 1기압에서 $1.44 \times 10^{-5}m/sec$이었다.

• Textile Coloration and Finishing
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• v.30 no.3
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• pp.199-207
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• 2018

In this study, the properties of polypropylene(PP) non-woven fabric spun under various conditions by the Melt-blown method were verified, and the deodorant content and deodorization of PP non-woven fabric after deodorant-treatment were investigated. PP non-woven fabrics are manufactured by varying the temperature of spin beam, hot air temperature and amount, the RPM of collector R/O and the distance between collector and spinneret, which affects the structure of the non-woven fabric. After that, the structural characteristics and air permeability of the non-woven fabric were measured. The experimental results show that the amount of air, the distance between the collector and the spinneret significantly affect the structural characteristics and air permeability of the PP non-woven fabric. And, regardless of the weight of the PP non-woven fabric, the deodorizing effect of UiO-66 MOF deodorant add-on ratio and content was higher.

• Korean Journal of Environmental Biology
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• v.41 no.4
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• pp.616-626
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• 2023

In May 2023, a free-living marine nematode species from the genus Parapinnanema was identified in the subtidal zone of Ulleungdo Island, the East Sea, Korea. Specimens were collected using the Smith-McIntyre Grab. These specimens exhibited close similarities to Parapinnanema imbricatum from the sublittoral of Moneron Island, particularly in terms of general characteristics, such as the detailed structure of the buccal cavity, the complex and ringed structure of the cuticle, the copulatory apparatus, spinneret, and the female genital system. However, the Korean specimens of Parapinnanema imbricatum also displayed distinctive features compared to the original description, including a relatively elongated body (3,317-4,339 ㎛ vs. 3,100-4,200 ㎛) and a narrower body width (66-77 ㎛ vs. 71-85 ㎛). Additionally, the diameter of the head was relatively shorter(24-29 ㎛ vs. 28-36 ㎛). This paper offers a comprehensive morphological description, along with illustrations and DIC photomicrographs, of P. imbricatum from Korean waters.

• Animal cells and systems
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• v.2 no.1
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• pp.145-152
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• 1998

The spinning apparatus and production of secretory silk from silk gland of the black widow spider, Latrodectus mactans were studied with scanning and transmission electron microscopes. The silk glands were located in seven groups on the spinnerets including each pair of major and minor ampullate, 3 pairs of tubuliform, 1 pair of flagelliform, 2 pairs of aggregate, about 50 pairs of pyriform and over 250 pairs of aciniform glands, respect- ively. Each group of silk gland feeds silk into one of the three spinneret pairs. Secretory silk is synthesized from rough endoplasmic reticulum (rER) of glandular epithelial cells. The secretory silk is transported from toe rER into the secretory vacuoles which are grown up by fusion with the surrounding small vesicles including the secretory silk. The secretory vacuoles, which show a gradual increase in electron density with the process of maturity, are formed without involvement of the Golgi complex, suggesting that they do not play an important role in the processing of the secretory silk. The secretory silk products are released by the mechanism of apocrine secretion, losing part of their cytoplasm. Moreover, another type of silk precursor, possibly protein, appears as granular material, and is also discharged to the luminal cavity.