• Journal of the Korean Chemical Society
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• v.53 no.6
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• pp.631-634
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• 2009

• Applied Chemistry for Engineering
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• v.5 no.5
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• pp.764-771
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• 1994

Electrochemical synthesis of conductive polypyrrole films was carried out in nucleophilic solvent containing p-toluenesulfonic acid or bezensulfonic acid as supporting electrolyte and dopant. Also characteristics of degradation and improvement of mechanical properties were studied. The conductivity, tensile strength and elongation of the films obtained in dimethyformamide/p-toluenesulfonic acid had the highest value of 10-40S/cm, $25N/mm^2$ and 10%, respectively. The optimum condition of electrochemical synthesis was $2mA/cm^2$ for constant current method and 0.9V for constant potential method containing 0.5M pyrrole and 0.5M p-TSA. The obtained films showed good stability in air and electrode characteristics of secondary battery by reversibility in doping and undoping. The degradation process was 1st order reaction at various temeprature. The activation energy and rate constant of degradation reaction were $1.01JK^{-1}mol^{-1}$ and $3.1{\times}10^{-7}min^{-1}$ respectively at $25^{\circ}C$. For the improvement of mechanical properties, composition of polypyrrole films with various host polymer were investigated and increase of tensile strength and elongation was confirmed.

• Membrane Journal
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• v.17 no.4
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• pp.329-337
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• 2007

This is the research about a new method to make the internal separation layer with smallest pore size in polyethersulfone (PES) membrane by adding p-toluenesulfonic acid (TSA) and polyvinylpyrolidone (PVP) to polymeric PES solution. The preparation and morphological characterization of PES sheet membranes containing PVP as a hydrophilic swelling material and TSA as a demixing material were performed. As a result by microflow porometery, the PVP and TSA added PES membranes showed good permeabilities and narrow pore size distributions, comparable to those of the commercial membranes. The concentration of PVP affected the PES characteristics on air permeability and surface structure. The concentration of TSA influenced on pore size distribution but do not affect air permeability. The surface images of FE-SEM shows similar pore size when TSA added or not. However, the cross-section images of FE-SEM show that the TSA added PES membranes have a increase of internal layer thickness with smallest pore size.

• Journal of Korea Foresty Energy
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• v.21 no.3
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• pp.1-9
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• 2002

Various types of acids, such as mineral acids, organic acids, and organic sulfonic acids, were used as catalysts in order to investigate their effectiveness during phenol liquefaction of pine bark. Hydrochloric arid was the most effective acid catalyst of the mineral acids used in this experiment for the phenol liquefaction, but the amount of the acid needed for more than 90% liquefaction was at least 11 mmol. Among the carboxylic acids used triflouroacetic acid (TFA) was effective for the liquefaction, but it was not possible to obtain liquefaction of more than 80%. Organic sulfonic acids, p-toluenesulfonic acid (PTSA) and methanesulfonic acid (MSA), showed remarkable effects for liquefaction, even in small amounts and at low liquefaction temperatures. Especially in the case of PTSA, a 92% liquefaction yield was obtained at the liquefaction condition of 14$0^{\circ}C$ for 2 h. Therefore, it was evident that the PTSA is a good acid catalyst for the phenol-pine bark liquefaction system.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.894-897
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• 2001

This experiment was to determine the optimum conditions for D-sorbitol cyclization in the presence of p-toluenesulfonic acid(p-TSA) as acid catalyst before the esterification of sorbitol with fatty acids. The optimum conditions of hydration reaction to obtain maximum yield of 1,4-sorbitan were at $130^{\circ}C$, 200mmHg reduced pressure, after l50min and l%(w/w) p-TSA. In this condition the yield of 1,4-sorbitan was approximately 90%.

• Analytical Science and Technology
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• v.13 no.4
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• pp.534-538
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• 2000

The title compound, $[Co(H_2O)_6](CH_3C_6H_4SO_3)_2$, has been prepared and characterized by X-ray crystallography. The crystal structure of the compound demonstrates a layered material constituted by hexaaquacobalt (II) cations and p-toluenesulfonate anions. Geometrical environment of the cobalt atom is octahedrally coordinated by water molecules. The p-toluenesulfonate anions are arranged with the sulfonate groups turned toward opposite side of the layer, alternately. The layered structure is stabilized by the hydrogen bondings between the ligated water molecules and the anionic sulfonate oxygen atoms.

• Bulletin of the Korean Chemical Society
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• v.11 no.1
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• pp.41-44
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• 1990

The rates of electropolymerization of pyrrole from aqueous solutions containing p-toluenesulfonic acid were studied as functions of the concentration of the surfactant anions and of temperature for the polymerization on the electrode surface immersed in the solution and also for the polymerization along the solution surface. In the case of the solution-surface polymerization, the polymerization rate showed maximum as the concentration of the p-toluenesulfonic acid changed at a fixed temsperature or as the temperature was varied at a fixed concentration. The decrease of the polymerization rate with increasing concentration or with rising temperature beyond the values at the maxima is interpreted as resulting from micelle formation.

• Journal of the Korean Applied Science and Technology
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• v.18 no.2
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• pp.127-135
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• 2001

Alkyl polyglucosides were synthesized by solvent-free glycosidation using ultrasonic emulsification. We examined glycosidation conditions of fatty alcohol with glucose hydrate and anhydrous glucose in the presence of p-toluenesulfonic acid. Glucose was emulsified in a molar excess of fatty alcohol for 20 minutes with a ultra-sonicator at room temperature and converted in a stirred reactor to more than 95% polyglucoside within $2.5{\sim}3.5$ hr under $20{\sim}30$ mmHg at $110^{\circ}C$ with a three-fold molar ratio of fatty alcohol to glucose in the presence of 1mol% p-toluenesulfonic acid. It was possible to obtain a polyglucoside mixture of HLB 13 consisting of 65% monoglucoside and 35% oligoglucoside with less than 1% of fatty alcohol.

• Bulletin of the Korean Chemical Society
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• v.20 no.12
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• pp.1433-1436
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• 1999

The 2-(2,4-dimethoxyphenyl)-4-MDO (2) underwent polymerization with ring opening as well as cyclization reaction in the presence of various cationic catalysts such as boron trifluoride, trifluoromethanesulfonic acid, p-toluenesulfonic acid, hydrochloric acid and trifluoroacetic acid. They afforded a mixture of the ring-opened poly(keto ether) and 3(2H)-dihydrofuranone derivative. Both the methylene group and oxygen atom of 1,3-dioxolane ring were participated in the reaction with cationic catalyst. The contents of the polymer and cyclization product were variable according to the acid strength of the cationic catalysts.

• Journal of the Korean Chemical Society
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• v.22 no.5
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• pp.334-339
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• 1978

The hydrolysis of ${\alpha}$-bromophenylacetamide in the acidic media has been studied. The reactions in sulfuric acid and p-toluenesulfonic acid afforded mainly mandelic acid ; on the other hand, in hydrochloric acid ${\alpha}$-chlorophenylacetic acid was the main product. In either case, it was difficult to obtain ${\alpha}$-bromophenylacetic acid without concomittant formation of mandelic acid and ${\alpha}$-chlorophenylacetic acid respectively from the hydrolysis of ${\alpha}$-bromophenylacetamide. Mandelic acid and ${\alpha}$-chlorophenylacetic acid were obtained in good yields (86, 95 %) in sulfuric and hydrochloric acid respectively; the reactions are therefore potentially useful processes for obtaining them.