• Journal of the Korean Society of Clothing and Textiles
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• v.36 no.11
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• pp.1237-1245
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• 2012

The effect of hydrophilicity and hydrophobicity of PET fabric on the detergency of particulate soil were investigated as functions of the concentration of hydrophilic and hydrophobic chemicals, surfactant concentration, ionic strength, adhesion and removal time, and pH. The detergency of the particulate soil was determined by the adhesion of particles to and their removal from fabric, the PET fabric and ${\alpha}-Fe_2O_3$ were used as textile materials and for the model of particulate soil, respectively. The hydrophilic and hydrophobic finish for PET fabric was treated with a polyester, silicone and fluorine organic compound of resin respectively. The adhesion of particulate soil to fabric treated with hydrophobic chemicals were slightly higher but its removal from fabric treated with hydrophobic chemicals was largely higher than fabric treated with a hydrophilic chemical regardless of solution conditions such as the concentration of hydrophilic and hydrophobic chemicals, surfactant concentration, ionic strength, adhesion and removal time, and pH. Therefore, hydrophobic treatment for fabric had a more positive effect than the hydrophilic treatment on the detergency of particulate soil.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2009.03a
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• pp.239-240
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• 2009

• Membrane and Water Treatment
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• v.10 no.4
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• pp.287-298
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• 2019

Lotus leaf has a special dual micro and nano surface structure which gives its highly hydrophobic surface characteristics and so-called self cleaning effect. In order to endow PVDF hollow fiber membrane with this special structure and improve the hydrophobicity of membrane surface, PVDF hollow fiber composite membranes was obtained through the immersion coating of poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) dilute solution on the outside surface of PVDF support membrane. The prepared PVDF composite membranes were used in the vacuum membrane distillation (VMD) for the desalination. The effects of PVDF-HFP dilute solution concentration in the dope solution and coating time on VMD separation performance was studied. Membranes were characterized by SEM, WCA measurement, porosity, and liquid entry pressure of water. VMD test was carried out using $35g{\cdot}L^{-1}$ NaCl aqueous solution as the feed solution at feed temperature of $30^{\circ}C$ and the permeate pressure of 31.3 kPa. The vapour flux reached a maximum when PVDF-HFP concentration in the dilute solution was 5 wt% and the coating time was kept in the range of 10-60 s. This was attributed to the well configuration of micro-nano rods which was similar with the dual micro-nano structure on the lotus leaf. Compared with the original PVDF membrane, the salt rejection can be well maintained which was greater than 99.99 % meanwhile permeation water conductivity was kept at a low value of $7-9{\mu}S{\cdot}cm^{-1}$ during the continuous testing for 360 h.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.8
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• pp.1444-1452
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• 2001

Textile materials are frequently in contact with surfactant solutions during their manufacturing or finishing processes as well as cleaning processes in use. Liquid wetting, wicking and absorbency of textile materials, and the liquid properties, surface characteristics and pore geometry of textile materials, and the liquie-solid interactions, In this paper, 10 different nonionic surfactants, including Span 20, Twen 20, 40, 60, 80, 21, 61, 81, 65, 85, were used. The surfactants were characterized by their hydrophile-lipophile-balance (HLB) values, structures, and surface tensions. The 0.1g/dL and 1.0g/dL surfactant solutions, which were both above critical micelle concentration (CMC), were used to see the concentration effects on the wetting and absorbency of cotton fabrics. The wetting behavior and liquid retention properties of hydrophobic cotton fabrics with different nonionic surfactant solutions are reported. The contact angles are greatly decreased and the water retention values are greatly increased by adding most of the surfactants studied into the system. The extents of this effects are influenced by the characteristics of surfactants and its solutions. Hydrophilic surfactants which have low number of carbon atoms or unsaturated hydrophobe structures are more effective in improving the wetting and absorbancy of hydrophobic cotton fabrics. The water retention of hydrophobic cotton fabrics has positive relations with $cos{\theta}$, adhesion tension and work of adhesion. The 1.0g/dL surfactant solutions show similar, but slightly improved wetting and absorbency characteristics of hydrophobic cotton fabrics compared to the 0.1g/dL surfactant solutions.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10a
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• pp.51-52
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• 2003

In order to understand the buffering behavior of hygroscopic fabric under subzero conditions, microclimates of the wool and PET clothing system were measured and compared. Vertical type Man-Clothing-Environment simulator was used to measure the microclimate at the environmental temperature of -10$^{\circ}C$. Buffering capacity was quantified by calculating from the depth and width of the hyperbolic curve of the graph. Hydrophilic wool fabrics showed better buffering capacity at the transient state than hydrophobic PET fabrics; which is attributed to the heat of sorption.

• Journal of the Korean Society of Clothing and Textiles
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• v.17 no.1
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• pp.151-161
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• 1993

The purpose of this study was to investigate the effect of hydrophilic finish for polyester (PET) fabric and hydrophobic finish for cotton fabric on the water transport and comfort properties. Polyester fabric was treated with 10% sodium hydroxide solution to impart hydrophilicity. Cotton fabric was sprayed with Scotch-gard$^{(R)}$ water and oil repellent finish to impart hydrophobicity. Porosity, air permeability, contact angle, wickability and water vapor transport rate (WVTR) were measured to determine the water transport properties of fabrics. To compare the comfort properties of treated and untreated fabrics, wear test was performed by putting fabric patches on the upper back: stratum corneum water content (SCWC), subjective wettedness and comfort rating were determined. The results were as follows: (1) The contact angle of water on treated polyester fabric was decreased and that of treated cotton fabric was increased. Also, the wickability of treated polyester fabric was increased and the wickability of cotton fabric was decreased. (2) Although each finish did not change porosity, the water vapor transport rate of treated polyester fabric was increased and that of treated cotton fabric was decreased slightly. (3) The results of stratum corneum water content measurements showed good agreement with the results of the contact angle and the wickability, i.e., the better the liquid water transport properties are, the less the stratum corneum water contents were resulted. (4) The realtionship of subjective wettedness or comfort and stratum corneum water content was independent. Therefore, it was concluded that human perception on the subjective wettedness or the comfort is affected by the skin contact of wet fabric rather than by the stratum corneum water content.

• Fashion & Textile Research Journal
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• v.25 no.1
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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.

• Fibers and Polymers
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• v.5 no.2
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• pp.151-155
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• 2004

Cold plasma of $O_2$ or Ar was irradiated on hydrophobic Kapton surface to attenuate or remove the electrostatic potential. A measurement on charge dissipation speed clarifies the obscure effect of plasma. These consequences reveal that $O_2$ plasma etching is more effective than Ar plasma. After 30 days, the dissipation speed of accumulated charge on initially etched sample has not changed under summer season.

• Journal of the Korean Society of Clothing and Textiles
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• v.19 no.6
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• pp.946-954
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• 1995

The purpose of this study is to modify the hydrophobic property and dyeability of polyethylene terephthalate fiber. Methacrylic acid (2nA) was graftpolymerized with benzoyl peroxide (BPO) as initiator onto polyethylene terephthalate fabrics. The results were as follow; 1. Graft-polymerization exhibited maximum graft ratio at a temperature of 100"C. 2. The polymer was gradually grafted in great amount to the surface of MA-g-PET as graft ration increase; with the cross-section examination of MA-g-PET, it was discovered that graft-polymeriation had also taken place inside the textile core. 3. Dyes absorption of basic dyes and disperse dyes was improved as craft ratio increase; with resistance to laundering, the former showed grade 3-4 and the latter showed grade 5.de 5.

• Journal of the Korean Society of Clothing and Textiles
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• v.27 no.5
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• pp.554-559
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• 2003

A newly developed contact angle measurement instrument by laser beam projection allows for rapid and direct determination of contact angles. The instrument may have a possibility to characterize newly developed nano-fibers. When the laser beam impinges on an edge of an interface of liquid and solid, projected beam were split across and made two straight lines on a tangent screen. From the result, it could measure the contact angle directly by reading the angle between two split beams. The purpose of this study was to prove reliability and reproducibility of the contact angle measurement instrument by laser beam projection compare to the conventional one by microscope through the comparative experiment and questionnaire. Test samples were selected by consideration of hydrophilic and hydrophobic, such as nylon 6 and polypropylene, respectively. The laser contact angle measurement has accurate, fast and convenient method to measure contact angle, and it can be a unique method to characterize nano-fibers.