• Textile Coloration and Finishing
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• v.20 no.6
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• pp.26-34
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• 2008

Wool fabric having high moisture content were treated with fluorocarbon-based water and oil repellent finishing agents by pad-dry-cure system. Three types of finishing agents which were regular-type or nano-type were adapted to compare the surface chemical composition, water and oil repellent property, crease recovery angle, and durability to repeated laundering. From the surface chemical compositions resulted by ESCA and C1s curve-fitting, it was shown that the regular-type finishing agent were easily taken off from the finished wool fabrics after repeated laundering. On the other hand, the fluoroalkyl groups of nano-type finishing agents turned round from fabric surface to fiber internal after repeated laundering. The water repellency of the wool fabrics treated with regular-type agent had a little changes according to the treatment condition changes and sharply decreased with repeated laundering. However, these values when treated with nano-type agents increased with the concentration and cure temperature and were maintained after 20 times laundering. The wool fabrics treated with nano-type agent had a great oil repellency irrespective of treatment conditions. Furthermore, the wrinkle recovery values of the wool fabrics treated with nano-type agents were higher than those of the fabrics treated with regular-type agent and were unchanged after 20 times laundering.

• Applied Chemistry for Engineering
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• v.33 no.6
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• pp.588-593
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• 2022

The effects of P₂O₅-doped on the surface of MgO particles on hydrolysis, water repellency, and insulation behavior were investigated. P₂O₅-doped MgO has exhibited a unique electrical property, which is significant insulation behavior due to both the suppression of the hydrolysis reaction by P₂O₅ and water repellency. Therefore, the insulation behavior was inversely proportional to the hydrophilicity and the Mg(OH)₂ and OH^-charge transfer ratio by the surface hydration reaction of MgO. The insulation of MgO according to aging was strongly influenced by the surface hydration reaction, the band gap of the added dopant species, and the hydrophilicity and hydrophobicity of the dopant. Finally, it was to show electrical insulation by inhibiting the surface hydration reaction of the hydrophilic MgO, which has a great potential for use in heat transfer medium applications.

• Textile Coloration and Finishing
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• v.24 no.3
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• pp.173-179
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• 2012

Silk fabric treated with fluorocarbon resins (Asahi Guard AG-7005 and AG-E061) were washed and subsequently heat treated varying the washing cycles and the temperature. After the processing, the water and oil repellencies, and contact angle to water were evaluated. The water and oil repellencies decreased by the washing and recovered by following heat treatment. Also ESCA measurement was carried out to investigate the surface chemical composition of the treated fiber. The $F_1s$ intensity of the treated fabric decreased by the washing and recovered by the subsequent heat treatment. On the other hand, the $O_1s$ intensity increased by the washing and decreased by following heat treatment. From the results, it is clear that change of the water and oil repellencies of the silk fabric treated with fluorocarbon resin occurred by the washing and subsequent heat treatment. Considering a change of the water repellency of the silk fabric treated with fluorocarbon resin, it seems likely that the fluoroalkyl group of the fluorocarbon resin rotates from surface to inside of the fiber by the washing to adapt to the hydrophilic circumstance, and the orientation of the fluoroalkyl groups of the resin disturbed by the washing recovers the orientation to the fiber surface after the subsequent heat treatment.

• Journal of the Korean Applied Science and Technology
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• v.13 no.3
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• pp.137-144
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• 1996

Durable softening water repellents such as PODCW, PDDCW, and PEDCW were prepared by blending cationized polymers, fatty carbamide, waxes, and emulsifiers. The cationized polymers included poly (octadecyl methacrylate-co-2-diethylaminoethyl methacrylate) [PODC], poly (n-dodecyl methacrylate-co-2-diethylaminoethyl methacrylate) [PDDC]and poly (2-ethylhexyl methacrylate-co-2-diethylaminoethyl methacrylate) [PEDC]. After the PET fabrics were treated with these water repellents, water repellency, softness, and durability of the PET fabrics were examined by various methods : water repellency by the hydrostatic pressure and the contact angle methods, softness by crease recovery and tearing strength, and durability by washability, respectively. Rating of water repellency of PET fabrics treated with PODCW was $80^{+}$, but those treated with PDDCW and PEDCW were not high enough to be used in industry.

• Journal of the Korean institute of surface engineering
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• v.29 no.6
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• pp.781-787
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• 1996

Silicom oxide films with good water repellency were prepared by rf plasma-enhanced CVD (rf-PECVD) using four kinds of organosilicon compound, which had different number of methyl ($CH_3$) groups, and oxygen as gas sources. The differences in the deposition rates, film composition and film properties were studied in detail. Water repellency depended on the number of $CH_3$ groups in the organosilicon compounds and the partial pressure of oxygen in the plasma. The highest contact angle for water drops, about 95 degrees, was obtained when trimethy lmethoxy silane (TMMOS) was used. The contact angle decreased with the amount of oxygen gas introduced into the plasma. The dissociation of $CH_3$ groups by adding oxygen was comfirmed by Fourier transform infrared spectroscopy(FTIR) and X-ray photoelectron spectroscopy (XPS). The optical properties were estimated by double-beam spectroscopy and ellipsometry. The transmittance of the glass plate coated by the film prepared with tetramethoxy silane (TMOS) was about 90% and the refractive index of film was 1.44. This value was smaller than the refractive index of a glass plate(soda lime glass, refractive index is 1.515) and this film played a role of anti-refractive coating.

• Journal of the Korea Furniture Society
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• v.25 no.3
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• pp.207-212
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• 2014

With increased interests in environmental issues, people are looking for new materials that serve special and bio-activated functions. One of interesting materials is charcoal which has excellent adsorption ability for harmful volatile organic compounds, fireproof performance, far-infrared ray emission, and electromagnetic shielding. Since non-crack carbonized board was developed from wood-based composite materials, carbonization method might be applied to woodcraft products such as wood cup and bamboo. In this study, manufacture of wood charcoal bowl was conducted with carbonization method developed in 2009 in order to activate wood products market. Ash tree(Fraxinus rhynchophylla) cup was carbonized at $600^{\circ}C$ with two pretreatments which were phenol resin and wood tar solution treatment. After carbonization of ash tree cup, non-crack charcoal cup were successfully manufactured. Phenol resin treatment affected on charcoal cup manufacturing both positively and negatively. For a positive way, it prevented shrinkage. For a negative way, it decreased water repellency. On the contrary, wood tar treatment accelerated shrinkage a bit and increased water repellency. Based on the results, wood tar can be used as pre-treatment solution for reducing post-treatment costs. We confirmed woodcraft products can be carbonized without deformation, so carbonization may provide a high value-added products from wood.

• Journal of Environmental Science International
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• v.13 no.10
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• pp.947-953
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• 2004

Waterborne fluorinated acrylate copolymer (WFAC) for surface modification of textile was synthesized from perfluoroalkyl ethyl acrylate, octadecyl acrylate, glycidyl methacrylate, surfactant and 3,3 methyl-methoxy butanol. The structures of the synthesized WFAC were determinated by FT-IR and $^{19}F-NMR$ analysis. The thermal stability investigated with DSC and TGA was decreased with increasing the content of fluorinated acrylate in the copolymer. However, the particle sizes of WFAC were increased with increasing the content of fluorinated acrylate in the copolymer. The surface energies calculated by contact angles of WFAC were in the range of 29.80$\~$13.41 dyne/cm. On the observing SEM of the textile surface treated with WFAC, the textile was swollen and compacted with increasing the concentration of water repellency agent. WFAC synthesized in this study showed a good water repellency.

• Journal of the Korean Applied Science and Technology
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• v.13 no.1
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• pp.41-46
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• 1996

Durable softening water repellents such as PODCWs were prepared by blending cationized compound of poly(octadecyl methacrylate-co-2-diethylaminoethyl methacrylate), of which synthetic methods were reported in the previous paper, activated polythylene, waxes, and emulsifiers. Water repellency of prepared PODCWs was measured by performing water repellent finish to various fabrics, PODCWs showed a good water repellency for P/C blended fabrics and their repelling tendency was in the order of P/C blended fabrics>cotton fabrics>nylon taffeta. The initial water repellencies of PODCW-1 and PODCW-2 were 100 and $100^{-}$ points, respectively, for P/C blended fabrics. And also, PODCW-1 and PODCW-2 were confirmed as durable water repellents with the results of making little difference of water repellency as ${\pm}5$ point after and before washing.

• Journal of the Korean institute of surface engineering
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• v.52 no.1
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• pp.37-42
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• 2019

Electrodeposited zinc layer is widely used as a sacrificial anode for a corrosion protection of steel. In this study, we modified the surface of electrodeposited zinc to have a hydrophobicity, which shows various advanced functionalities, such as anti-corrosion, anti-biofouling, anti-icing and self-cleaning, due to its repellency to liquids. Superhydrophobicity was realized on electrodeposited zinc layer with a hydrothermal treatment, creating nanostructures on the surface, and following Teflon coating. The superhydrophobic surface shows a great repellency to water with high surface tension, while liquid droplets with low surface tension easily adhered on the superhydrophobic surface. However, immiscible lubricant-impregnated superhydrophobic surface shows a great repellency to various liquids, regardless of their surface tension. Therefore, it is expected that the lubricant-impregnated surface can be an alternative of superhydrophobic surface, which have a drawback for some liquids with a low surface tension.

• Journal of the Korea Concrete Institute
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• v.16 no.4 s.82
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• pp.477-484
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• 2004

As a part of durability improvement of concrete-structure, penetrating water repellency of liquid type is applied to concrete surface. Besides, a related standard is made recently, but the standard has been prescribe for initial settlement state of penetrating water repellency of liquid type, to the exclusion of performance variation depending time and outdoor environment factor. For measurement of performance variation, we measured the weight of outdoor exposure specimen every regular intervals and check a measured value against a measured value of different condition specimen. Moreover, after the application of penetrating water repellent, measured a adhesive strength in tension between cement-polymer modified waterproof coatings and surface of specimen. The applied penetrating water repellent is a emulsified silicon type with a deep penetration depth. In view of the results so far achieved, the more a Quantity of application and active solid content does get, the deeper penetrating water repellency of emulsion type Penetrate get longer and supplied moisture increase in quantity, a penetrating water repellency of liquid type penetrates more deep, but a quantity of water absorption increase gradually. Perhaps this result is caused by a reduction of active solid content on concrete surface, because active ingredient is moved into the concrete by dissolution.