• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.1
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• pp.48-56
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• 2000

The objective of this study was to investigate the enzymatic deinking technology. Office recycled papers such as computer printed out(CPO) and white ledger(WL) were used in the evaluation of four different deinking conditions ; alkaline deinking , neutral deinking and enzymatic deinking at alkaline and neutral pH. Filltering pads were prepared after flotation deinking to measure brighteness gain and ink removal efficiency. Three different surfactants were also used in the evaluation of deinking efficiency including surface chemical properties by measuring foam height and stability, surface tension and cloud point of views. The results indicated that the neutral deinking method with enzyme and surfactant addition showed highest deinking efficiency of office recycled papers.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.2
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• pp.270-281
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• 1996

This study was carried to figure out the effect of bleaching on the cationic surfactant (DSDMAC) absorption by cotton fabrics. And physico-chemical change, static electricity, and fabric stiffness of bleached cotton fabrics were measured. Cotton fabrics bleached with sodium hypochlorite soluton and with sodium percarbonate solution were used to analyze the DADMAC absorption. The results were as follows: 1. As the number of bleaching cycles were increased, the degree of oxidation on cotton fabrics was increased. So their carboxyl content was increased and their tensile strength was decreased. 2. DSDMAC absorption by cotton fabrics was increased by bleaching and was in propor- tion to carboxyl content. Therefore, it was groved that DSDMAC absorption by cotton fabrics was motivated by ion exchange mechanism. 3. The static electricity of cotton fabrics almost no change when bleached and unbleached absorption had no effect on the static electricity of cotton fabrics. 4. DSDMAC which was absorbed by cotton fabrics acted as a lubricant. DSDMAC absorption reduced the friction coefficient of yarn, so stiffness of cotton fabric was decreased.

• Journal of the Korean Ceramic Society
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• v.36 no.7
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• pp.705-710
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• 1999

Stability and chemical durability for aqueous casting of BaTiO3 slurry with polycarylic acid(PAA) were studied. PAA was well chemisorbed on surface of BaTiO3 powder at neutral pH but did not chemically adsorbed at low pH. The amount of Ba dissolution in aqueous BaTiO3 slurry was abruptly increased at strong acid pH2 and also at high amount of PAA. Protection of Ba dissolution and stability of slurry could be obtained through the optimization of slurry conditions such as pH amount of surfactant and solid content.

• Journal of the Korean Applied Science and Technology
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• v.21 no.4
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• pp.380-387
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• 2004

The preparation of $CaSO_4$ nanoparticle by vesicles formed spontaneously in cationic OTAC and anionic ADS mixed surfactant solution whose ratio is 0.3/0.7 is investigated. Added electrolytes for preparing nanoparticles reduce vesicle size about 200-300 nm comparing with that of pure vesicle whose size is 700-800 nm by DLS. The core of vesicles has 200 nm size and acts as nanoreactors which same size of monodisperse $CaSO_4$ nanopaticles are formed. Although $CaSO_4$ particles are formed at the outer of vesicles, they are very large and amorphous. The formed particles are identified with XRD analysis after separation due to coinciding with $CaSO_4$ particles.

• Journal of the Korean Applied Science and Technology
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• v.25 no.1
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• pp.83-90
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• 2008

The core-shell latex particles were prepared by sequential emulsion polymerization using alkyl methacrylate as a shell monomer and potassium persulfate (KPS) as an initiator. We study the effects of core-shell structure of calcium carbonate/alkyl methacrlyate in the presence of an anionic surfactant sodium lauryl sulfate (SLS) and polyoxyethylene alkyl ether sulfate (EU-S133D)). The structure of core-shell polymer were investigated by measuring to the thermal decomposition of polymer composite using thermogravimetric analyzer and morphology of latex by transmission electron microscope (TEM).

• Proceedings of the Korea Concrete Institute Conference
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• 1996.10a
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• pp.253-259
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• 1996

The purpose of this study is to investigate the fundamental properties of polyurethan concrete. Polyurethane must be expanded by means of a blowing agent during polymerization. Chemical blowing is caused by the reaction water with isocyanate. Binder system for polyurethane concrete is based on polyol and isocyanate with catalyst, surfactant, and methyl chloride. Polyurethane concretes are prepared with various grading of aggregate, and tested for compressive, flexural strengths, flow test, foaming multiple proportion, working life, condition of surface, distirbution of aggregate. From the test results, the foaming of polyurethane concretes are affceted by amount and grading of aggregate. Workability increases with raising amount of methy chloride and working life reduced according to amount of catalyst. The mix proportion of B with methyl chloride of 1% and catalyst of 0.1g for polyurethane concrete is recommended in consideration of strengths, condition of surface and balance between cost and performance.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.13 no.1
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• pp.15-28
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• 1987

Silica spheres were prepared by interfacial reaction method. Factors in-fluencing to the mean particle size and specific surface area of silica spheres were investigated. The experiment about the surface modification of silica spheres was carried out. It was observed that silica spheres have characteristics of the spherical shape with the vacancy in the inner side, high surface area, and reaction tendency by many silanol group. The mean particle size of silica spheres is dependent on the surfactant concentration and W/O ratio. The specific surface area is influenced by SiO2/Na2O mole ratio in sodium silicate. Silica spheres coated with titanium dioxide or zirconium dioxide improve the UV protection effect. Titanate and silane coupling agent make chemical bond with silica surface and improve the organophile and the dispersibility of silica spheres.

• Proceedings of the SCSK Conference
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• 2003.09b
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• pp.192-199
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• 2003

Trimethylglycine, commonly named betaine, is the most simple amphoteric molecule. It is completely vegetal (1,2), as it is produced in the sugar industry by industrial chromatography of molasses. While abundantly used in foods and diet supplements, many interesting applications in cosmetics have recently been investigated, like its capability to increase the volume and stability of foams in surfactant solutions. For its special chemical structure (it is the internal salt of a weak acid and a strong alkali) trimethylglycine is a solvent and buffering agent for strong acids and Lewis' acids. It allows to improve the efficiency of $\alpha$- and $\beta$-hydroxy acids in increasing the physiological rate of epidermal cell renewal, while keeping a low skin-irritation level. In oral care cosmetics, it acts as a mucous membrane protectant (3). For its special water co-ordination capability, its solubilising power, polymer swelling capability, after-feel improvement in hair products, skin moisturization and elasticity enhancing properties, trimethylglycine provides unusual characteristics to many products intended for skin maintenance (4).(omitted)

• Journal of the Society of Cosmetic Scientists of Korea
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• v.7 no.1
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• pp.53-76
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• 1979

During cosmetic treatments, SURFACTANTS penetrate into KERATINOUS TISSUES (hair, skin and nails). Whereas some of these surfactant molecules migrate to the vital tissues, a considerable fraction remains bound to the keratin. The extent of binding depends both on the nature of the head group and the length of the hydrophobic tail of the detergent molecules. In addition to entering the amorphous region of the keratin, some of the detergents also penetrate into the crystalline microfibrils and change their structures affecting their tensile properties. Owing to an uneven distribution of detergent molecules in the tissues, an anisotropy of the elastic moduli will occur, resulting in considerable internal stresses which, in rum, might lead to a deterioration of hair, skin and nails. The chemical behavior of keratins is also influenced by the presence of absorbed detergent in their structures. Depending on the detergents and the conditions, these effects can be either protective or detrimental. The deposition of detergent molecules into keratin can be enhanced or diminished by the inclusion of appropriate ingredients into the product formulae.

• Journal of the Korea Concrete Institute
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• v.26 no.1
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• pp.63-70
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• 2014

This experimental study was intended to improve the compressive strength of multi-walled CNT reinforced cementitious composites with efficiency. The variables considered are the degree of sonication, the amount of surfactant, the replacement ratio of silica fume, etc. Optical microscope informed that fiber dispersion of CNT was improved with the increase of sonication time, and the compressive strength was proved to be enhanced as the degree of sonication increased. When superplasticizer as a surfactant had SP/CNT ratio of 4~6, the best improvement in strength was obtained. Silica fume was shown to produce the highest compressive strength at 10% replacement. Microstructure of CNT composites was also analyzed; XRD and SEM results indicated that CNT addition hardly changed hydration products and microstructure, and MIP analysis found the reduction of total porosity as well as the increase of nano-pores with the size of tens of nm instead of the decrease of pore distribution in the region of around 10 ${\mu}m$ and 100 nm. The results of microstructure analysis explains that the strength improvement is closely related to physical contribution rather than chemical influence by adding CNT.