• 한국염색가공학회지
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• 제31권4호
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• pp.276-287
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• 2019

In this study, cotton fibers were coated with a different weight percentage of octadecyl dimethyl(3-triethoxy silylpropyl) ammonium chloride(ODDMAC) to improve antimicrobial and water repellent properties. First, the ODDMAC dissolved in ethanol to prepare a solution. Then the cotton fibers were immersed in the ODDMAC/ethanol solution for 10 minutes at ambient temperature and dried at 80℃ for 3 minutes followed by curing. The treated cotton fibers were characterized by scanning electron microscopy(SEM) and x-ray photoelectron spectroscopy(XPS). The treated cotton fibers revealed sufficient antimicrobial activity against Klebsiella pneumoniae(ATCC 4352) and Staphylococcus aureus(ATCCBAA-1707). The hydrophobic nature of the treated cotton fibers was characterized by contact angle measurement. The results showed that the cotton fibers treated with the ODDMAC showed excellent hydrophobic properties which improved to 121°.

• 한국염색가공학회지
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• 제18권5호
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• pp.30-34
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• 2006

Polypropylene fiber was dyed with 4 super hydrophobic dyes having different alkyl derivatives on the same chromophore. Double-tailed cationic surfactant, didodecyldimethylammonium bromide(DDAB), was used to make dye-dispersant complex to improve the dispersion of dyes. As the alkyl groups are longer and the hydrophobicity is increased, the dyeability onto polypropylene fiber was improved and deep coloration was obtained. As for the fastness properties, wash fastness was relatively good, while light fastness was bit low.

• Membrane and Water Treatment
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• 제10권4호
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• pp.251-257
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• 2019

Fabricating hydrophobic porous membrane is important for exploring the applications of membrane distillation (MD). In the present paper, poly(vinylidene fluoride) (PVDF) hollow fiber membrane was modified by coating polydimethylsiloxane (PDMS) on its surface. The effects of PDMS concentration, cross-linking temperature and cross-linking time on the performance of the composite membranes in a vacuum membrane distillation (VMD) process were investigated. It was found that the hydrophobicity and the VMD performance of the PVDF hollow fiber membrane were obviously improved by coating PDMS. The optimal PDMS concentration, cross-linking temperature and cross-linking time were 0.5 wt%, $80^{\circ}C$, and 9 hr, respectively.

• 한국식품영양과학회지
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• 제24권3호
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• pp.446-453
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• 1995

The improtant components of extracellular matrix(ECM) are collagen and chondroitin sulfate. The hydrophobic surface of collagen is one of the determining factors of diameter of collagen fiber and also is closely related to the aging phenomena. The controlling mechanism of the diameter of collagen fiber influenced by the interaction with chondroitin sulfate was evaluated using bis-ANS as a hydrophobic probe. Hydrophobic surface area of collagen molecule shielded by chondroitin sulfate was evaluated. Relative fluorescence intensity of collagen in thepresence of chondroitin sulfate was measured using bis-ANS as a hydrophobic probe. The fluorescence intensity decreased with the increase in chondroitin sulfate up to 3.8 chondroitin sulfate/collagen(mole/mole). Further increase in the ratio of chondroitin sulfate to collagen did not change the fluorescence intensity. Similar changes in the relative fluorescence intensity were observed for both rat tail and lathyrific rat skin collagen. The fluorescence intensity indicated by the binding between bis-ANS and hydrophobic sites of collagen was pH dependent, and the shielding effect of collagen-chondroitin sulfate interaction could not be detected at pH above 6.0. This is probably due to the charge repulsions caused by negative charged collagen molecules at higher pH.

• 한국염색가공학회지
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• 제29권4호
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• pp.223-230
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• 2017

Three super hydrophobic fluorescence dyes were selected to dye high molecular weight polyethylene fiber and their molar absorptivity, emission spectrum, and quantum yield were measured. From the results of color strength on the fiber, all the three dyes exhibited linear increase according to the dye concentration and Fluoro3 dye showed the highest color strength among them. Emission strength of the fluorescence dyes on the fiber was investigated according to the dye concentrations. The emission was increased with the increase of the dye concentration at relatively low dye concentration and then after showing the maximum emission strength the emission was decreased at higher dye concentrations. The highest emission was obtained in Fluoro2 dye. Color fastness to washing and rubbing was generally good enough, however, especially to light, only Fluoro3 dye exhibited rating 3 acceptable practically and Fluoro1 and 2 was ratings 1 which is unacceptable level.

• 한국전기전자재료학회논문지
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• 제11권3호
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• pp.174-180
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• 1998

In this work, the properties of FRP, which is applied recently in the composite insulating materials, by thermal treatment were investigated. The specimens were epoxy glass laminates fabricated by thermal press method and had the volume content of 46[%] cutted $45^{\circ}C$ in the fiber direction and 1.0[mm] thickness. The experimental results showed that the amount of weight loss, wettability, surface potential, and surface resistivity increased up to 200[$^{\circ}C$] as a function of temperature. Usually, most degradations caused the hydrophilic to decrease the contact angle. But, in this work on thermal-degradated FRP, we can confirm the introduction of hydrophobic properties by cross-linking and the ablation of polar small-molecules rather than chain scission and oxidation. Finally, weight loss and contact angle increased. These phenomena show the existence of hydrophobic surface. With the change to the hydrophobic surface and the electrical potential and resistivity on FRP surface increased. But, the dielectric properties and tensile stength are decreased.

• 펄프종이기술
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• 제45권5호
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• pp.30-36
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• 2013

Hydrophobic property of Kapok fiber was investigated by sequential removal of its components by different extraction methods. Acetone extraction for the removal of the hydrophobic extractives, holo-cel-lulose preparation after the removal of lignin and xylan extraction by potassium hydroxide was applied. The degree of hydrophobicity of each samples were measured by the water sorption ability. The water sorption ability of Kapok fiber was increased by the sequential treatment of acetone extraction, holocellulose preparation and xylan removal. Based on holocellulose compositional analysis by $^1H$-NMR spectroscopic method, the unusual high amount of the acetyl groups in the holocellulose of Kapok partially contributed to the hydrophobicity of Kapok holocellulose fiber.

• 한국염색가공학회지
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• 제30권4호
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• pp.237-244
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• 2018

Three super hydrophobic red fluorescence dyes were selected to dye high molecular weight polyethylene fiber. Their absorbance and emission spectra were obtained and Stokes' shift was measured. Fluorescence emission strength of the dyes on the fiber was investigated and therefore Fluoro Red 3 was determined as the best one among those three dyes in this experiment. Dyeing properties and fluorescence intensities were investigated using the Fluoro Red 3 on high molecular weight polyethylene fiber at various dyeing conditions. The optimum concentration of a dispersing agent was appeared at 10wt% in aqueous solution. The best dyeing was obtained at $125^{\circ}C$ for 1 hour. The color fastnesses to the washing and rubbing were as high as ratings 4~5, however, the fastness to light was exhibited ratings 2~3.

• 한국의류산업학회지
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• 제25권1호
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• pp.119-126
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• 2023

This study aimed to determine the effects of relative humidity and fiber properties on the moisture permeability of multilayer systems by measuring water vapor transmission in the overlapping condition of various fabrics. The results confirmed that the property of the fabric in contact with the humid environment affects the moisture permeability. If the layer facing the humid environment is hydrophobic and the layer facing the dry environment is superhydrophobic, water vapor transmission increases by up to 17.8% compared to the opposite conditions. Comparing the correction values of the water vapor transmission reflecting the thickness of the specimen under the multilayer condition showed that permeability was higher when the hydrophilic or hydrophobic layer was facing the humid environment. The opposite was true from the "push-pull" effect of absorption mechanism. In the case of moisture permeability, the more hydrophilic the surface facing the humid environment, the more permeable that water vapor diffuses and passes through. It was concluded that the "pull-push" effect, in which water vapor diffuses widely through the hydrophilic facing a humid environment and then passes through the hydrophobic layer, contributes to the improvement of permeability. Permeability differed according to the multilayer overlapping condition. When the relative humidity was high, the "pull-push" effect was insignificant. This is caused by water droplets absorption after the partial migration of water due to condensation. These results suggest that the overlapping conditions and properties of fabrics should vary depending on heavy sweating or not.

• 한국염색가공학회지
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• 제33권4호
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• pp.258-268
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• 2021

This study conducted on the introduction of recycled cellulose fibers, which are widely used in the textile industry as eco-friendly biomass materials, into polypropylene resins, which are mainly used for interior and exterior materials such as door trims and console parts of automobiles. In general, cellulose fibers can affect mechanical properties and have a lightening effect when used as a reinforcing agent. However, since cellulose fibers have hydrophilic properties and have relatively low compatibility with industrial polymer resins, they are used in combination through fiber hydrophobic surface treatment. Therefore, through this study, the reforming reaction conditions optimized in terms of hydrophobicity and workability for cellulose fibers are studied. Furthermore, polypropylene containing surface-modified cellulose fibers was prepared to compare physical properties by fiber content and study optimized content.