• Applied Chemistry for Engineering
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• v.16 no.4
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• pp.502-506
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• 2005

In the presence of various clays, nylon/clay nanocomposites were synthesized by anionic polymerization of ${\varepsilon}$-caprolactam (CL) via monomer casting method. The effect of each clay on polymerization reaction was investigated and the change in gallery structure of clays during polymerization was analyzed by X-ray diffraction. When the three kinds of organo-clays were used in the amount of 2 wt% of CL, polymerizations were not successful due to an increase in viscosity during polymerization. Significant changes were not observed in the mechanical and thermal properties of the composites containing organo-clays with 1 wt%. On the other hand, composites containing natural clay up to 5 wt% were successfully prepared, and the composite with 5 wt% showed a decrease in tensile strength and elongation, and remarkable improvement in thermal properties.

• Polymer(Korea)
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• v.38 no.6
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• pp.791-800
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• 2014

4-Chlorobenzoyl (CB) group-attached multi-walled carbon nanotube (c-MWNT) was prepared via a direct Friedel-Crafts acylation of MWNT with 4-chlorobenzoic acid (CBA) in a $P_2O_5$/poly(phosphoric acid) medium. c-MWNT with a maximum chlorine content of 5.3 wt% (CB group content of 20.9 wt%) was obtained by controlling the amount of CBA during the reaction. Using a self-condensation polymerization of 4-chlorobenzenethiol (CBT) to poly(phenylene sulfide) (PPS), MWNT-g-PPS was prepared by adding c-MWNT of chlorine content of 5.3 wt% during the self-polymerization of CBT and removing homo PPS after polymerization in order to increase the interfacial interaction between PPS and MWNT. Thermal and surface properties of the MWNT-g-PPS were characterized. The results showed that PPS was formed on the surface of c-MWNT by the condensation of c-MWNT and CBT.

• The Journal of Korean Physical Therapy
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• v.4 no.1
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• pp.13-18
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• 1992

Most of the electromagnetic agents used in physical therapy rely for their effects on tissue heating and photoreaction of the body. Infrared and untraviolet light on the other hand, owns its place in medicine because it produces direct photochemial reaction when it interacts with the body. This study was carried out to investigate and review for photoreaction of the akin. The results were an follows. 1. The effects of the infrared are heat production, increasing metabolism, increasing circulation, vasodilatation and pigmentation. 2. Directed photoreactions are divided into acute reaction and chronic reaction, and the acute reaction makes pigmentation from $290\~320nm$ of ultraviolet ray. 3. Ultraviolet ray formated pigmentations, which are melanoblasts excited from ultraviolet ray and received chemical stimulation, that make melanin granule. 4. If exposured with long duration, at ultraviolet ray, it makes skin thickening and epithelioma. 5. Indirected photoreaction is made by existenced hypersensitivity of photoreaction or lack of photodefence structure. 6. The phototoxic reactions are synthesized by chemical reaction of excitement from ultraviolet ray also this time analysis, synthesis and polymerization from energy of a circumferenced substance. 7. Sunscreen substances are P-amino benzoic acid and oxidate titan.

• Elastomers and Composites
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• v.14 no.1
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• pp.7-12
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• 1979

Graft copolymerization of methlymethacrylate(MMA) onto sodium alginate(SA) aqueous solution by sodium metaperiodate$(NaIO_4)$ as an initiator was carried out with the variation of the reaction time, the reaction temperature and the concentrations of initiator and monomer. The results obtained were as follows: 1. SA was easily separated from the reaction mixture of homopolymer, graft polymer and sodium alginate ungrafted by the treatment of concentrated boiling $Na_3PO_4$, solution with the small amount of $Na_2SO_3$ to the mixture and then isolated as the acid form by acidifying the salts solution containing SA. 2. The amount of graft polymer was larger than that of homopolymer below $70^{\circ}C$ whereas above $70^{\circ}C$ the amount of homopolymer was larger. 3. The sum of each amount of graft polymer ana homopolymer was always increased with increase of the reaction time, the reaction temperature and the concentrations of initiator and monomer. 4. With increase of the concentration of initiator, the graft efficiency was increased below $70^{\circ}C$ while decreased above $70^{\circ}C$. 5. Graft copolymerization of MMA onto SA in aqueous solution was carried out without initiator.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.4 no.3
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• pp.209-213
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• 2003

Polyaniline (PANi) composite particles were synthesized by chemical oxidation polymerization of aniline in presence of poly-n-isopropyl acryl amide (PNIPAM). The PANi particles formed in the reaction medium deposited onto non-conducting PNIPAM template to produce PANi-coated composite particles. The formation of composite was confirmed by FT-IR spectroscopy, and UV-VIS spectroscopy, and their morphological structures were examined by scanning electron microscopy (SEM). From the experimental results, it was determined that PANi was successfully coated onto non-conducting PNIPAM.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.583-586
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• 2000

Many different oligosaccharides were produced by transferring the fructose residue of sucrose to maltose, cellobiose, lactose and sucrose (self-transfer), where their yields of fructosylated acceptor products accounted for $26{\sim}30%$ (w/w). The maximum conversion yield (30%) was obtained in fructosyl cellobioside formation with 500 g sucrose/l (substrate) and 200 g cellobiose/l (acceptor). These four acceptors gave various products having DP (degree of polymerization) $2{\sim}7$ by successive transfer reactions.

• Journal of Environmental Science International
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• v.5 no.2
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• pp.203-210
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• 1996

To improve coagulation characteristics and to reduce dossage of chemicals in watertreatment, polyaluminium sulfate was manufactured by reaction of polymerization between aluminium sulfate and sodium aluminate. As the results of affirmation and performance test, the yield of product was about 24% from molecular cut on levels by ultrafilteration method. The type of molecular is nearly affirmated as a kind of complex like AIm(OH)n(3m-n)+ from Scanning Electron Microscopy (S.E.M.) and X-ray diffraction test. Since the synthesized polymer was supposed to be quasi, further study for stabilization was required.

• Journal of the Korean Ceramic Society
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• v.24 no.2
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• pp.133-138
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• 1987

The behavior of CaO and SiO2 in the reaction produced which produced in the early hydration of C3S was studied by XRD and thermal analyzer. Polymerization of hydrated siltcates was also studied by TMS method. TMS derivatives were separated by gaschromatography. Cao/SiO2 molar ratios of the produced CSH gel under the air atmosphere were higher than that in the CO2. Dimerization rate of hydrated silicates was very fast in the early hydration stage. Trimer began to appear later than dimer and its increasing rate was very low. The amount of dimer and trimer formed under the CO2 atmosphere was less than that in the air.

• Proceedings of the KAIS Fall Conference
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• 2003.06a
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• pp.334-336
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• 2003

Polyaniline(PANi) composite panicles were synthesized by chemical oxidation polymerization of aniline in presence of Poly-N-Isopropyl acryl amide(PNIPAM). The PANi panicles are formed in the reaction medium deposited onto non-conducting PNIPAM template to produce PANi-coated composite panicles. The formation of composite was confirmed by FT-IR spectroscopy, and UV-VIS spectroscopy, and their morphological structures were examined by scanning electron microscopy(SEM). From the experimental results, it was determined that PANi was successfully coated onto non-conducting PANIPAM.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.4
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• pp.375-383
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• 2007

Treatment efficiency research was performed using Fenton process and the electrochemical process in the presence of ferrous ion and hydrogen peroxide for the industrial wastewater including 1,4-Dioxane produced during polymerization of polyester. The Fenton process and the electrochemical Iron Redox Reaction (IRR) process were applied for this research to use hydroxyl radical as the powerful oxidant which is continuously produced during the redox reaction with iron ion and hydrogen peroxide. The results of $COD_{Cr}$ and the concentration of 1,4-Dioxane were compared with time interval during the both processes. The rapid removal efficiency was obtained for Fenton process whereas the slow removal efficiency was occurred for the electrochemical IRR process. The removal efficiency of $COD_{Cr}$ for 310 minutes was 84% in the electrochemical IRR process with 1,000 mg/L of iron ion concentration, whereas it was 91% with 2,000 mg/L of iron ion concentration. The lap time to remove all of 1,4-Dioxane, 330 mg/L in the wastewater took 150 minutes with 1,000 mg/L of iron ion concentration, however it took 120 minutes with 2,000 mg/L of iron ion concentration in the electrochemical IRR process.