• Archives of Pharmacal Research
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• v.8 no.4
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• pp.191-195
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• 1985

The polymerization of title compound (MCEC, I) with phenols led to give corresponding resole type polymer. Phenol and p-methoxyphenol polymer had a relative higher molecular weight and a property of elastomer, but p-chloro-and p-nitrophenol polymer had a lower ones. Also, phenol and p-meth-oxyphenol gave to crosslinking polymer by elongation of reaction period and rising of temperature.

• Applied Chemistry for Engineering
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• v.2 no.3
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• pp.199-208
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• 1991

Carbocationic polymerization is widely applied to prepare polymers from electron-rich monomers. The reaction is usually uncontrollable due to many side reactions and explosively fast rate of polymerization. In a living polymerization, however, the reaction is controlled as designed, and many workers reported many successful cases recently. In this review several ways of living carbocationic polymerization were illustrated, and they were connected together under a basic principle.

• Macromolecular Research
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• v.8 no.4
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• pp.147-152
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• 2000

The activity of periodic acid as an initiator for the polymerization of acrylamide in aqueous medium was investigated. The rate of polymerization was found to be proportional to the monomer concentration to the 1.5th power in the range of 1.41-5.64 mol/L. The reaction order to the periodic acid concentration was 0.49, which indicated a bimolecular mechanism for the termination reaction in the range of 0.5-4.0$\times$10$\^$-2/ mol/L. Propagation rate increased with raising the temperature according to an Arrhenius expression resulting in the exhibition of an apparent activation energy of 87.8 kJ/mol in the temperature range of 60-80$\^{C}$. The addition of hydroquinone as a radical scavenger stopped the polymerization of acrylamide initiated by periodic acid. These results support that the polymerization proceeds via a radical chain mechanism .

• Macromolecular Research
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• v.8 no.6
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• pp.247-252
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• 2000

Suspension polymerizations of styrene were conducted in the aqueous phase with tricalcium phosphate (TCP) as a stabilizer and $\alpha$, $\alpha$'-azobis(isobutyronitrile) (AIBN) as an initiator. Various amounts of initiator and stabilizer were selected and the reaction was carried out at a selected temperature between 60 to 80 $\^{C}$. It was found that the combination of 5 wt% stabilizer and 2.427$\times$10$\^$-3/ mol/L of costabilizer is the minimum amount for suspension polymerization reaction to produce particles in the aqueous phase. Particles were found to be polydisperse in diameter, regardless of reaction conditions. Class transitions were observed to be around 95$\^{C}$, nearly independent of reaction temperature and initiator. Homogenizer was found to be essential in forming particles in the proximity of tens of micrometers in diameter in suspension polymerization with TCP as stabilizer.

• Macromolecular Research
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• v.14 no.4
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• pp.466-472
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• 2006

The kinetic behavior of emulsion polymerizations of styrene in the presence of sulfonated N-hydroxy ethyl aniline (SHEA) was investigated with two initiators: 2,2'-azobisisobutyronitrile (AIBN) and potassium persulfate (KPS). SHEA was synthesized using a stepwise polyurethane reaction method from 3-hydroxy-1-propane sulfonic acid sodium salt, isophorone diisocyanate (IPDI), and N-(2-hydroxyethyl) aniline. Stable core-shell poly(styrene/sulfonated N-hydroxy ethyl aniline, St/SHEA) latex particles were successfully prepared by using an appropriate amount of AIBN, in which SHEA plays the role of 'surfmer', i.e., acting as both a surfactant in the emulsion polymerization and a monomer in the chemical oxidative polymerization. The kinetic behavior was dissimilar to that of typical emulsion polymerization systems. A long inhibition period and low rate of polymerization were observed due to radical loss by the oxidative polymerization of SHEA. It was concluded, due to the low water-solubility of AIBN and retardation reaction by SHEA, that the initial loci of polymerization were monomer droplets. However, growing polymer particles as polymerization loci became predominant as polymerization proceeded. It was suggested that AIBN was more effective than KPS in the preparation of the core-shell type poly(St/SHEA) latex particles. With KPS, no substantial polymerization was observed in any of the samples.

• Journal of the Korean Society of Safety
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• v.25 no.3
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• pp.61-65
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• 2010

Most of the chemical reactions performed in the chemical industry are exothermic, meaning that thermal energy is released during the reaction. It is also important to understand the thermal hazards such as thermal stabilities and runaway reactions, which are governed by thermodynamics and reaction kinetics of the mixed materials. The paper was described the evaluation of thermal behavior caused by an exothermic batch process in manufacture of the vinyl acetate resin. The aim of the study was to evaluate the thermal stabilities of raw materials with operating conditions such as a reaction inhibitor, heating rate, reaction atmosphere and the mount of methanol charged in the vinyl acetate polymerization process. The experiments were performed in the differential scanning calorimeter(DSC), C 80 calorimeter, and thermal screening unit($TS^u$). It was suggested that we should provide the thermal characteristics for raw materials to present safe precautions with operating conditions in the vinyl acetate polymerization process.

• Journal of the Korean Ceramic Society
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• v.36 no.2
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• pp.151-158
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• 1999

$\varepsilon$-Caprolactame as organic monomer was intercalated in the interlayer space of montmorillonite and polymerized by polymerization reaction so that the inorganic polymer and organic polymer could be combined each other by chemical bonding. The results of X-ray and IR analysis showed that the polymerization reaction of $\varepsilon$-caprolactame between the interlayer spaces has been performed sucessfully. In order to study polymeric reaction product in detail we have isolated the polymerized material from the interlayer space and analyzed it by X-ray diffractometer and IR-Spectrocopy. The comparison of these results with them of the analyses for thee pure polymer which has been synthesized by polymeric reaction of $\varepsilon$-carolactame without montmorillonite showed that the obtained both polymeric materials are the same compounds.

• Journal of the Korean Ceramic Society
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• v.42 no.4
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• pp.224-231
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• 2005

The polymerization of $\varepsilon-caprolactone$ in the layers of the [DEACOOH]-Montmorillonite intercalations complex was attempted using 10-Carboxy-n-decyldimethylethylammonium bromide and Na-Montmorillonite to achieve [DEACOOH]-Polycaprolactone-Montmorillonite in which the inorganic material (montmorillonite) and the organic material (polycaprolactone) are chemically linked each other. The results of X-ray- and IR-analysis for the samples obtained after polymerization showed that the polymerization reaction has been successfully accomplished. In order to study the polymeric reaction products more precisely we have separated the polymerized product from the silicate layers and analyzed it with X-ray diffractometer, IR-spectrometer and TEM. The comparison of the results of X-ray- and IR-analysis for the separated polymer with them for the polymer which was synthesized by the reaction of $\varepsilon-caprolactone$ only with the organic cation without montmorillonite showed that the obtained both polymers are the same compounds.

• Bulletin of the Korean Chemical Society
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• v.20 no.6
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• pp.663-666
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• 1999

The 4-methylene-1,3-dioxolane(4-MDO) derivatives with dimethoxyphenyl group on the 2-position of 1,3-dioxolane ring, 2-(x,y-dimethoxyphenyl)-4-MDO derivatives (x,y=2,3(1b), 2,4(2b), 2,5(3b) and 3,4(4b)) were prepared by acelalizationof the corresponding benzaldehyde with 3-chloro-1,2-propanediol, followed by dehydrochlorination. 2-(Dimethoxy)phenyl-4-MDO derivatives underwent polymerization wiht ring opening as will as cyclization reaction to afford a mixture of the ring-opened polymer and 3(2H)-dihydrofuranone derivative with boron trifluoride as a cationic catalyst. Both the methylene group and 1,3-dioxolane ring were participated in the reaction with cationic catalyst. The key intermediate of the polymerization is a benzyl cation generated by ring opening, and the cyclization reaction proceed via proton addition to oxygen atom of 1,3-dioxolane ring.

• Journal of Microbiology and Biotechnology
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• v.5 no.3
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• pp.177-180
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• 1995

In horseradish peroxidase-catalyzing polymerization of phenol under the water/dioxane solvent system, the optimal concentration of hydrogen peroxide was found to be 10 mmol/I. Feeding of hydrogen peroxide at its optimal concentration improved the polymerization performance by reducing reaction time and increasing molecular weights. Monomer conversions and the molecular weights of the enzymatically produced polymer were in the ranges of 83.1~94.2$%$ and 58000~68000, respectively.