• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.38 no.1 s.113
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• pp.62-69
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• 2006

This study was carried out to measure and analyze the storage condition, distribution route, and packaging method of four selected agricultural products(small tomato, cabbage, peach, and carrot) in the cold chain system. It was shown that dew-forming phenomenon by fruits and vegetables deteriorates the agricultural product quality and physical properties of corrugated fiberboard box during the cold chain system. The compressive strength deterioration in corrugated fiberboard boxes was much greater for single wall(SW) corrugated fiberboard containers than for double wall(DW) in low temperature-high humidity condition. To reduce the deterioration of box and dew-forming phenomenon, water-repellency treatment should be over $R_6$. However, water-resistant treatment of corrugated fiberboard containers would be effective under high relative humidity conditions more than 75% RH. It was suggested that functional corrugated fiberboard box packaging would be an optimum method to reduce the deterioration of agricultural products quality by. It was also achieved controlling the relative humidity and temperature during the storage and physical distribution process.

• Journal of the Korean Society of Clothing and Textiles
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• v.14 no.3 s.35
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• pp.216-221
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• 1990

This study was performed for the development of antimicrobial finished nonwoven fabrics with water repellency. And it was aimed to examine the changes of moisture related properties and air permeability of the finished fabrics. Viscose rayon nonwoven fabrics were treated with organic silicon quaternary ammonium salt having carbon numbers of 16, which was synthesized for this study Antimicrobial activity was evaluated by shake flask method and the reactivity of antimicrobial agent was measured by degree of luminescence from inductively coupled plasma. Water repellency of treated specimen was evaluated by dynamic water absorption measurement and air permeability was measured by Frazier method. The results obtained from this study were as follows: 1. Excellent antimicrobial activity was obtained for the high concentration of treatment and the durability of finishing after laundering was better as the treatment concentration was higher 2. Silicon contents taken up by specimen increased with increased treatment concentration. 3. Dynamic water absortion of treated specimen decreased compared to that of untreated. And, it was lowered as the treatment of concentration increased and as the silicon content increased. 4. Moistuie regain and uptake with lapse of time of treated specimen increased compared to those of untreated. But, air permeability of treated specimen decreased.

• Polymer(Korea)
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• v.29 no.5
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• pp.433-439
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• 2005

The copolymers were prepared by the emulsion copolymerization of fluoroalky lacrylate-stearylacrylate-m-isopropenyl-${\alpha},\;{\alpha}'$-dimethylbenzyl isocyanate (TMI) in order to obtain water repellent polymers. The respective copolymerization rates of the three monomers considerably depended upon the use of the nonionic emulsifier and the nonionic-cationic mixed emusifier, and the optimum conditions were obtained. The particle sizes of the copolymers were in the range of 105 to 222nm. The particle sizes of the copolymers prepared by the use of the mixed emulsifiers were smaller than those of the copolymers prepared by the use of the nonionic emulsifier. The reactions of both TMI-N-methyl acetamide and TMI-cellobiose did not take place. However, the reaction of TMI-n-butylamine occurred. The water contact angles before and after washing three times for nylon and poly(ethylene terephthalate) (PET) fabrics coated with the copolymer prepared by the use of mixed emulsifier were about $139^{\circ}\;and\;133^{\circ}$ Therefore, the copolymer showed good durable repellency for nylon and PET.

• Korean Chemical Engineering Research
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• v.54 no.3
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• pp.387-393
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• 2016

Fluorinated polyurethane coating solutions were synthesized from perfluoroalkyl alcohol, toluene diisocyanate, and polycarbonate diol as starting materials. Next, coating films were prepared by spin-coating the fluorinated polyurethane coating solutions on the PC substrates, followed by thermal curing at $120^{\circ}C$. The obtained fluorinated polyurethane coating films were characterized by FT-IR spectroscopy, UV-Vis spectrometer, contact angle tester and pencil hardness tester. Contact angle measurements of water on the coating films showed that the addition of perfluoroalkyl alcohol improved the water repellency and increased the contact angle from $81^{\circ}C$ to $111^{\circ}C$. However, the pencil hardness of coating films exhibited a constant grade of H, irrespective of the addition of perfluoroalkyl alcohol.

• Journal of the Korean Wood Science and Technology
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• v.47 no.3
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• pp.336-343
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• 2019

Effects of a novel mold inhibitor specifically for bamboo, on the properties of composite products have been confirmed in this study. The mechanical and dimensional stability properties of bamboo fiber-based composites (BFBCs) from different bamboo species were also investigated. The results showed that Burmanica Gamble possessed the highest values of modulus of elasticity (MOE) of 33.2 GPa, modulus of rupture (MOR) of 286.9 MPa, compressive strength of 182.6 MPa and shear strength of 24.0 MPa. By contrast, Phyllostochys heterocycla among all of species showed the lowest MOE of 16.3 GPa, MOR of 170.3 MPa and compressive strength of 128.9 MPa were the lowest among all of species. Moreover, there is a remarkable variation in the swelling and water absorption between the samples with 4 h and 28 h water immersion treatment, especially Phyllostachys iridenscens. Overall, the results suggested that TCIT (Tebuconazole and 3(2H)-isothiazolone) had no significant effect on the mechanical properties compared with the control condition, and it would be utilized as an antimould of BFBCs manufacturing.

• Journal of the Korean Wood Science and Technology
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• v.32 no.2
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• pp.50-57
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• 2004

This study attempted to evaluate the water repellency and drying effectiveness of linseed oil treated-solid wood at high temperature by immersion. The moisture content of green wood (Pinus densiflora) sample (above 90%) was reduced about 10% after 6 hours treatment at 150℃. When the treated samples were cut into cross section along the length, it was observed that the linseed oil penetrated into up to 20% of the sample cross section area in all locations. However, a strength loss of the specimen was not detected. The pre-drilling before linseed oil treatment was effective in reducing the defects such as checks and splits, and improved the linseed oil penetration into all samples from the surfaces. The result of water absorption test of treated-wood showed that the water repellent efficacy of treated-wood was greater than that of the control. The anti-fungal activity of treated samples using five sap stains and thee decay fungi was not detected in broad-spectrum toxic mechanism. However, decay test using white rot fungi (Tyromyces palustris) and brown rot fungi (Trametes versicolor) showed that the treated sample has a decay resistance to these two fungi.

• Textile Coloration and Finishing
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• v.10 no.1
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• pp.33-37
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• 1998

It is rather important in the water and oil repellent finishing for wool fabric what kind of water-repellent agents will be used. In many cases, Fluorocarbon-based water-repellent agents(eg.Oleophobol-S), the surface tensions of which very low, were recom-mended on account of good water and oil repellencies. In repellent finishing, fabrics were padded in a bath which contained aqueous solution of water-repellent agents, and wetting agents, followed by drying and curing. The most suitable treating condition for excellent repellency was as follows Fabrics were padded at liquor pick-up ratio of 50%, with aqueous solution which contained $30g/\ell$ of water-repellent agents, and $40g/\ell$ of wetting agents. And the padded fabrics were dried at $110^\circ{C}$ for 1 minute, and cured at $160^\circ{C}$ for 2 minutes. For the fabrics, water and oil repellencies and durability to repeated dry-cleanings are observed.

• Journal of the Korean Applied Science and Technology
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• v.5 no.1
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• pp.63-70
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• 1988

The quaternized compound of the copolymer between 2-diethylaminoethyl methacrylate and stearyl methacrylate (DSACC) was chosen as the mother resin for the water repellent of acrylics. The quaternized compound of 1-lauroyl dis (amino ethyl)-2-dodecyl imidazoline (LDDIC) was used to promote softening effect and hydrostatic pressure for the water repellent. The water repellent (EDUWC) obtained from the DSACC and LDDIC blended with waxes and emulsifiers improved the properties such as the water repellency, washable, tear strength and crease recovery when it was treated on the nylon fabrics with and without the resin. The reaction mechanism between the Nylon fiber and EDLWC was examined, and EDLWC was confirmed as the durable water repellent.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.6
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• pp.16-23
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• 2018

In this study, Polydimethylsiloxane (PDMS) was applied to Strain Hardening Cement Composites (SHCC) for penetrating water repellency. The penetration depth of PDMS, strength of SHCC, and chloride ion penetration resistance of SHCC were investigated. As a result of measuring penetration depth of PDMS when applying different application method, it was confirmed that all methods satisfied the requirements of KS F 4930. Although the immersion method showed the largest penetration depth, the spray method was considered to be more appropriate considering the ease of field application. Compressive strength tests showed that the penetration depth of PDMS decreased as the compressive strength of SHCC increased. The compressive strength of M4-A and M4-B specimens with large PDMS penetration depths decreased by 9.6% and 8.0%, respectively, compared with those of M4 specimens produced without PDMS. Compressive strengths of the M1-A and M1-B specimens with small PDMS penetration depths were reduced by 4% and 2.2%, respectively, compared with the M1 specimen. As a result, it can be seen that the strength reduction rate of SHCC increases as the penetration depth of PDMS increases. The chlorine ion penetration tests showed that the chlorine ion penetration resistance increases with the penetration depth of PDMS.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.112-113
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• 2014

This study was done to resolve the air reduction in mortar when mixed with ERCO. Effects of the water repellent ALC powder due to its particle size and substitution ratio on the cement mortar with ERCO was analyzed. Results showed more water repellent ALC powder ensured more air but did not affect the size of particles. It was determined the compression was caused by more air and water added to achieve the flow. Therefore, substituting with water repellent ALC powder may compensate for the air reduction in mortar with ERCO. Other measures and approaches are needed in order to resolve the reduced strength.