• 한국건축시공학회지
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• 제12권3호
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• pp.332-339
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• 2012

In this study, six mortar mixes were tested in order to examine the significance and limitations of hydrophilic fiber in terms of its capacity to enhance the tensile resistance of Hwangtoh mortar. Lyocell, polyamide and polyvinyl alcohol (PVA) fibers were selected for the main test parameters. The tensile capacity of mortars tested was evaluated based on the splitting tensile strength and the modulus of fracture, while their ductility was examined using the toughness indices specified in ASTM. Test results showed that the addition of lyocell and PVA fibers had little influence on the flow of the Hwangtoh mortars. To enhance the tensile capacity and toughness index of Hwangtoh mortar, it is proposed that fiber spacing above 0.0003 is required, regardless of the type of fiber.

• 한국추진공학회지
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• 제23권5호
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• pp.36-42
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• 2019

본 연구에서는 리오셀 섬유를 사용하여 탄소직물을 제조함에 있어, 인계 난연제인 Phosphoric Acid(PA)와 가교제인 Melamine resin (MR)을 사용하여 섬유의 전처리를 수행하고 TGA, FT-IR, XRD, 중량 분석을 통하여 물리적, 화학적 구조 변화에 대하여 고찰하였다. 전처리를 통하여 내염화 및 흑연화된 직물의 경우 미처리 직물과 비교하여 중량 수율이 14.7%, 직물 폭과 길이의 수율이 각각 15%, 15.5% 증가함을 확인하였다. 이러한 결과는 셀룰로오스의 탈수반응을 촉진과 함께 섬유 표면에 char를 형성하고, 셀룰로오스 분자 내의 가교반응을 유도하여 내염화 시 안정한 구조 형성에 의한 효과로 설명할 수 있다.

• 한국염색가공학회지
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• 제15권4호
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• pp.43-50
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• 2003

N-methylmorpholine-N-oxide(NMMO) is recently hewn as a solvent dissolving cellulose to produce a new regenerated cellulosic fiber, lyocell. In this study, four kinds of cellulosic fibers (lyocell, regular cotton, treated cotton with 50% and 75% NMMO aqueous solution) was examined and compared in terms of mechanical properties and dyeability. The swelling of cotton treated with NMMO aqueous solution is higher than that of cotton treated with water. In dyeing rate, the cotton treated with NMMO was faster than regular cotton. NMMO treatment decreased the crystallinity of cotton fabrics and improved their softness and smoothness.

• Carbon letters
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• 제27권
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• pp.112-116
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• 2018

• 공업화학
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• 제26권4호
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• pp.394-399
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• 2015

본 연구에서는 Cu 촉매가 도입된 활성탄소섬유를 제조하여 고효율 $SO_2$ 흡착재를 제조하였다. 라이오셀 섬유를 내염화 및 탄화공정을 통해 탄소섬유를 얻었으며, $SO_2$ 흡착능을 향상시키기 위해 KOH 활성화를 사용하여 높은 비표면적 및 균일한 미세기공구조를 부여하였다. 활성탄소섬유에 Cu 촉매를 도입하기 위하여 $Cu(NO_3)_2{\cdot}3H_2O$ 수용액을 사용하였으며, 공정 시 i) 탄소섬유 내 산소 관능기의 분해반응을 촉진하고, ii) 산화구리 및 질산염의 분해로 oxygen radical이 생성되어 탄소섬유의 활성화 반응을 촉진시켰다. 이로 인해 활성탄소섬유의 미세공과 중기공 형성효과 및 탄소섬유 표면에 고르게 분산된 Cu 촉매를 확인하였다. Cu 촉매 도입 후, 활성탄소섬유에 비해 비표면적 및 미세공의 비율이 약 10% 이상 증가되었고, $SO_2$ 흡착능이 149% 이상 향상된 결과를 얻을 수 있었다. Cu 촉매도입공정 시, 전이금속 촉매효과에 의하여 발달된 미세공, 중기공 및 비표면적에 의한 물리적 흡착과 도입된 Cu 촉매에 의한 $SO_2$ 가스의 화학적 흡착반응의 시너지 효과에 기인하여 $SO_2$ 흡착능이 향상된 것으로 사료된다.

• 한국항공우주학회지
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• 제49권5호
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• pp.355-363
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• 2021

리오셀계 탄소/페놀릭 복합재료의 항공우주용 내열 부품 적용 가능성을 확인하기 위하여 내열성능 평가 및 열 해석을 수행하였다. 탄소/페놀릭의 열반응 평가는 내열성능평가모터(Thermal Protection Evaluation Motor, TPEM)로 수행되었다. 본 논문에서는 열 해석을 위해 유체의 경계층 해석을 고려한 경계층 적분 코드와 삭마 및 열분해를 고려한 MSC-Marc 2018 코드를 사용하였다. 추진기관의 압력 곡선, 연소 시험 후 절개된 목삽입재 시편을 통하여 삭마 및 단열성능을 분석하였고, 리오셀계 탄소/페놀릭 복합재료의 열반응은 레이온계 탄소/페놀릭 재료와 유사하였다. 연소시험을 통한 결과를 바탕으로 국산 리오셀계 탄소/페놀릭의 항공우주용 내열 부품으로의 적용 가능성을 확인하였다.

• Carbon letters
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• 제23권
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• pp.69-73
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• 2017

• 한국의류산업학회지
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• 제26권2호
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• pp.190-197
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• 2024

With increasing global interest in environmentally friendly materials and the consequent rise in demand, there is a growing need for alternatives to synthetic fibers, which can cause skin diseases and other side effects. The fashion industry is emphasizing material sustainability owing to concerns about increasing carbon emissions. Moreover, consumers express a strong desire for ecofriendly and sustainable materials. Therefore, clothing brand companies are developing eco-friendly products to enhance their corporate image. Hemp fibers are recognized for their functionality and are utilized as crucial materials in the development of eco-friendly products by global fashion companies. In this study, we produced socks that effectively improve foot health using hemp stem bark extract fibers and demonstrated the positive efficacy of natural fibers through functional and wearability evaluations. Hemp stem bark extract fibers showed 99.9% antimicrobial effectiveness against bacteria responsible for sweat-induced bacterial proliferation and odor, when blended with lyocell fibers and woven into fabric to manufacture socks. Wearability evaluations of these terry cloth socks confirmed a reduction in foot odor and fatigue among the participants with a consumer satisfaction of 4.63/5. These findings confirm the effectiveness and positive impact of the natural antimicrobial properties of hemp fibers and terry cloth structure in improving foot health.

• Fibers and Polymers
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• 제6권1호
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• pp.28-34
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• 2005

The purpose of the research was to examine the effect of three different levels of enzyme treatment on the physical characteristics and the end-use suitability of the lyocell fabrics made with four different types of commercial wood pulp. The appropriate enzyme concentration for obtaining an optimum as well as consistent physical characteristics and fabric hand trait was 3 g/l for the concentration levels tested in the present investigation. Weight loss was more affected by higher enzyme con­centration than other physical properties. H2 was least affected by enzyme treatment for all three physical properties and fab­ric hand. 5 g/l concentration exhibited little difference from 3 g/l in the physical characteristics, whereas the KES-FB values indicated a significant loss of fabric hand in most PHV s with the 5 g/l concentration level. Among different garment parame­ters, all four fabric types were relatively inappropriate for the men's slacks (MS) fabric due to the lower hand value of koshi required by the MS parameter. However, despite the relatively low koshi values, high fukurami values required for men's dress shirt (MWDS) resulted in the highest THV among the four garment parmeters. The four fabric types, which represent the usage of four different wood pulps, in general seem to exhibit a higher applicability to women's winter thin dress (WWTD) than women's winter suit (WWS) garment parameter.

• 복식문화연구
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• 제24권6호
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• pp.777-787
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• 2016

This study was carried out in order to provide useful data for planning fabrics of summer eco-friendly fashion products. The fabrics used in this study were four cellulose fibers: cotton, cotton/mulberry blended, flax, and flax/lyocell blended. Dyeing with natural indigo was carried out under three different reducing conditions (i.e., general, eclectic, and eco-friendly) that have different reducing agent and pH levels, and hydrosulfite and glucose were used as a reducing agent. The dye uptake (K/S value) of fabrics dyed with natural indigo by a reducing condition was the highest at 660nm. Regardless of the fabrics, dye uptake was the highest under the general reducing condition and the lowest under the eco-friendly reducing condition. Under different reducing conditions, the dye uptake of natural indigo fabrics with the maximum absorption wavelength indicated a difference. The colorfastness of cellulose fabrics that were dyed with natural indigo had a rate of 4 to 5 except for rubbing fastness, which indicated good colorfastness. Additionally, natural indigo-dyed cotton and flax fabrics had good antibiosis. When the color characteristics of fabrics dyed with natural indigo were measured, all of the three reducing conditions created purple blue (PB) colors, and the color characteristics of dyed fabrics by reducing condition and fabric showed significant differences.