• Macromolecular Research
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• 제16권3호
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• pp.253-260
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• 2008

Environmentally friendly biocomposites were made using plant-based natural fibers, such as henequen and kenaf. The natural fiber reinforced polypropylene (PP) and unsaturated polyester (UP) biocomposites were examined in terms of the reinforcing effect of natural fibers on thermoplastic and thermosetting polymers. Kenaf (KE) and henequen (HQ) fibers were treated with an electron beam (EB) of 10 and 200 kGy doses, respectively, or with a 5 wt% NaOH solution. Four types of biocomposites (KE/PP, HQ/PP, KE/UP and HQ/UP) were fabricated by compression molding and each biocomposite was characterized by dynamic mechanical analysis and thermogravimetric analysis. The kenaf fiber had the larger reinforcing effect on the dynamic mechanical properties of both PP and UP biocomposites than the henequen fiber. The highest storage modulus was obtained from the biocomposite with the combination of UP matrix and 200 kGy EB treated kenaf fibers.

• 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.

• 패션비즈니스
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• 제26권3호
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• pp.87-97
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• 2022

This study investigated the dyeability and color change of the natural dyes of SeaCell, a biodegradable functional fiber that is permanently added to cellulose fibers with natural additives extracted from seaweeds. The natural dyes used in the study are five dyes. Gardenia and turmeric, which are yellow-based natural dyes, Sappan wood and Lac, which are red-based natural dyes, and Indigo, a blue-based natural dye, were selected. The dyeability and color change according to the change of the mordant conditions and the number of times of dyeing were investigated. In addition, the dyeing properties and colors of cotton and silk fibers were compared under the same dyeing conditions as SeaCell. The study results are as follows. It was found that SeaCell had lower dyeing properties than silk, a protein fiber, in gardenia, sappan wood, and lac dyes, but had higher dyeing properties than cotton with the same cellulose component as SeaCell fibers. In the case of turmeric, it showed higher dyeing properties than cotton except for the no mordant condition. In the case of Indigo dye, SeaCell shows the best dyeability, indicating that it is a very suitable fiber for Indigo dyeing. As sustainable functional fibers are continuously developed in the future, natural dyes that are environmentally friendly and human-friendly are actively introduced and commercialized, and it is expected that they can be used as reference materials.

• 한국염색가공학회지
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• 제13권4호
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• pp.241-248
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• 2001

Natural indigo dyeing has been used mainly on cellulosic fibers and silk during the course of history in Korea. In order to extend the usage of this one of the most important natural dyes, its dyeability on wool fabrics has been studied to find out the optimum dyeing condition for wool fiber which is susceptible to alkaline medium. The dyeing method used was hydrosulphite vat of extracted dye. K/S values of dyed fabrics were investigated to analyze the dyeability of natural indigo on wool fibers and colors were measured through $L^*,\;a^*,\;b^*$ and Munsell Values. Highest K/S values were obtained at the temperature of 60(C and pH 7 to 8. The Munsell Values for hue of wool fabrics dyed with extracted indigo powder using hydrosulphite vat fell mostly in PB range. As the dyebath pH increased, blueness increased. Different dyeing conditions resulted in change of colors of dyed fabrics due to the difference in amounts of indigotin and indirubin contents within the dyed fiber as shown by HPLC.

• Geomechanics and Engineering
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• 제32권4호
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• pp.361-373
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• 2023

This study aimed to investigate the engineering properties and mechanical behaviors of polymer-fibers treated sand. Para rubber (PR), natural fiber (NF), and geosynthetic fiber (GF) were used to reinforce poorly graded sand. A series of unconfined compressive and splitting tensile strength tests were performed to analyze the engineering behaviors and strength enhancement mechanism. The experiment results indicated that the PR-fibers mixture could firmly enhance the strength properties of sand. The stress-strain characteristics and failure patterns have been changed due to the increase of PR and fibers content. The presence of PR and fibers strengthened the sand and enhanced the stiffness and ductility behavior of the mixture. The stiffness of reinforced sand reaches an optimum state when both NF and GF are 0.5%, while the optimum PR contents are 20% and 22.5% for the mixture with NF and GF, respectively. An addition of PR and fiber into sand contributed to increasing interlocking zone and bonding of PR-sand interfacial.

• Computers and Concrete
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• 제24권1호
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• pp.19-35
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• 2019

In this paper, the effect of the type and amount of fibers on the physicomechanical properties of concrete containing fine recycled refractory brick (RRB) and natural aggregate subjected to elevated temperatures was investigated. For this purpose, forta-ferro (FF), polypropylene (PP), and polyvinyl alcohol (PVA) fibers with the volume fractions of 0, 0.25, and 0.5%, as well as steel fibers with the volume fractions of 0, 0.75, and 1.5% were used in the concrete containing RRB fine aggregate replacing natural sand by 0 and 100%. In total, 162 concrete specimens from 18 different mix designs were prepared and tested in the temperature groups of 23, 400, and $800^{\circ}C$. After experiencing heat, the concrete properties including the compressive strength, ultrasonic pulse velocity (UPV), weight loss, and surface appearance were evaluated and compared with the corresponding results of the reference (unheated) specimens. The results show that using RRB fine aggregate replacing natural fine aggregate by 100% led to an increase in the concrete compressive strength in almost all the mixes, and only in the PVA-containing mixes a decrease in strength was observed. Furthermore, UPV values at $800^{\circ}C$ for all the concrete mixes containing RRB fine aggregate were above those of the natural aggregate concrete specimens. Finally, regarding the compressive strength and UPV results, steel fibers demonstrated a better performance relative to other fiber types.

• 패션비즈니스
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• 제11권2호
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• pp.92-101
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• 2007

This research was carried out following the preceding research on natural cellulose fabrics dyed with extract of fresh african marigold petals. Dyeability on fabrics was tested by dyeing with wool and silk which are natural protein fibers. Dyeing tests were carried out under different pH of the dye solution and mordants, examining the changes in the surface color, K/S value, and maximum absorption wavelength. The probability of improving dyeability was investigated by pre-mordanting with pre-treated chitosan. Wool fabrics showed color tone of medium or less saturation and brightness, in dark yellow color series. An orange color of high saturation was only obtained by tin mordanting. Wool showed higher K/S value than cellulose fibers. In summary, marigold dye has more affinity for protein fibers. It showed better dye effect in wool than silk. The chitosan pre-treatment and pre-mordanting lowered the K/S value of wool, which showed that chitosan pre-treatment does not improve dye uptake. However, different from the dyeing carried out by pre-mordanting without pre-treatment with chitosan, more diversified colors could be obtained by mordants. Therefore, for the dyeing natural protein fibers with marigold extract, post-mordanting does not require chitosan pre-treatment. However, pre-mordanting with chitosan pre-treatment could implement diverse colors. Considering its dyeing behaviors which are similar in both natural cellulose and protein fibers, african marigold extracts can be evaluated as a stable and highly practical dye.

• Composites Research
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• 제20권2호
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• pp.32-38
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• 2007

Natural fibers can refer to all types of fibres only produced by nature. Their lengths vary from particles to long strands. Natural fibers are categorized roughly by six types, depending on the types of sources; base, leaf, seed, grasses, fruit and wood. Of these fibers, jute, flax, sisal and ramie are the most commonly used as reinforced materials in preparing polymer composites. In development and improvement of these composites, many studies have been implemented to overcome the drawbacks such as incompatibility, moisture problems and so on. The range of industry sectors of natural fiber-reinforced polymer composites becomes more extensive gradually and many of the companies all over the world are engaged in fabrications or applications. This paper mainly discussed the recent status of the domestic/overseas market and research issues of natural fiber-reinforced polymer composites. We made an exception of wood-polymer composites market which have played a great role because they had been often dealt with.

• 펄프종이기술
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• 제43권2호
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• pp.66-71
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• 2011

Biocomposites were fabricated with biodegradable polymers and natural fibers. Biocomposites have benefits of low cost, low density, and biodegradability over inorganic fiber composite, and give comparable strength properties. Hydrophobic polymer used for sizing in paper industry, AKD (Akenyl Keten Dimer), was applied to natural fibers, red algae fibers (RAF) in this study, to make fiber surfaces more compatible to hydrophobic nature of matrix polymers. Composites with RAF, kenaf, glass fibers, and carbon fibers have been fabricated by a compression molding method and their thermo-mechanical properties have been studied. Also, the thermal dimensional stability test was done from at 30 to $100^{\circ}C$. The storage moduli and the thermo-mechanical stabilities of polypropylene and poly lactic acid based biocomposites were improved by reinforcing with the RAF and much more with AKD treated fibers. Dimensional stability of biocomposite was also markedly improved by AKD pretrement on RAF.

• 한국건설순환자원학회논문집
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• 제2권2호
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• pp.115-127
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• 2014

Addition of fibers in cement or cement concrete may be of current interest, but this is not a new idea or concept. Fibers of any material and shape play an important role in improving the strength and deformation characteristics of the cement matrix in which they are incorporated. The new concept and technology reveal that the engineering advantages of adding fibers in concrete may improve the fracture toughness, fatigue resistance, impact resistance, flexural strength, compressive strength, thermal crack resistance, rebound loss, and so on. The magnitude of the improvement depends upon both the amount and the type of fibers used. In this paper, locally available waste fibers such as coir fibers, sisal fibers and polypropylene fibers have incorporated in concrete with varying percentages and l/d ratio and their effect on compressive, split, flexural, bond and impact resistance have been reported.