• Fibers and Polymers
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• v.7 no.1
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• pp.20-25
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• 2006

The alkaline dissolution behavior of sea-island type polyarnide microfibers were successfully monitored using a cationic dye staining method. Weight reduction behavior of the alkali-treated microfiber fabrics and the treated fabrics stained with cationic dye were investigated in a comparative manner. The termination of dissolution monitored by both methods was also confirmed by scanning electron microscopy.

• Bulletin of the Korean Chemical Society
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• v.28 no.4
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• pp.667-674
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• 2007

Phase behavior for the mixed aqueous surfactant systems of cationic octadecyl trimethyl ammonium chloride (OTAC)/anionic ammonium dodecyl sulfate (ADS)/water was examined. Below the total surfactant concentrations of 1.5 m molal, mixed micelles were formed. At the total surfactant concentrations higher than 1.5 m molal, there appeared a region where mixed micelles and vesicles coexist. As the surfactant concentration increased, the systems looked very turbid and much more vesicles were observed. The vesicles were spontaneously formed in this system and their existence was observed by negative-staining transmission electron microscopy (TEM), small-angle neutron scattering (SANS) and encapsulation efficiency of dye. The vesicle region was where the molar fraction α of ADS to the total mixed surfactant was from 0.1 to 0.7 and the total surfactant concentration was above 5 × 10-4 molality. The size and structure of the vesicles were determined from the TEM microphotographs and the SANS data. Their diameter ranged from 450 nm to 120μm and decreased with increasing total surfactant concentration. The lamellar thickness also decreased from 15 nm to 5 nm with increasing surfactant concentration and this may be responsible for the decrease in vesicle size with the surfactant concentration. The stability of vesicles was examined by UV spectroscopy and zeta potentiometry. The vesicles displayed long-term stability, as UV absorbance spectra remained unchanged over two months. The zeta potentials of the vesicles were large in magnitude (40-70 mV) and the observed longterm stability of the vesicles may be attributed to such high ζ potentials.

• Journal of the Korean Home Economics Association
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• v.20 no.2
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• pp.45-51
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• 1982

Degree of separation and adhesion of dye and stain particles has been measured usually by the rate of reflection of light. However, it could be proved that the relation between the quantity of stain and the rate of reflection greatly varied with kinds of stain and states of adhesion. For this study, several pieces of cotton and polyester having different states of stain adhesion were prepared by staining them with two kinds of artificial stain different in color: Ferric Oxide and Ferric Oxynate. Every piece went through soilremoval test which employed two surfactants: Anionic LAS and Cationic M2-100. After the operation, relations between quantity of pre-soilremoval stain and rate of reflection were measured, as well as those between quantity of post-soilremoval stain and rate of reflection. Rate of reflection and quantity of stain were not proportional in measurement to the pieces stained with Ferric Oxide and Ferric Oxynate. The consequence was also the same with cotton and polyester. That held true of the fat-stained textile. With the same quantity of stain, rate of reflection varied according to the magnitude of stain particles, and the state of adhesion influenced the magnitude of stain particles a great deal.