상용화제 SEBS-g-MA가 PA6/PP-g-MA 블렌드계의 나노 고차구조에 미치는 영향

고재송,이창형,최형기,한애란,나재운 한국공업화학회 2003 공업화학 Vol.14 No.3

Polyamide 6 (PA6)/maleated polypropylene (PP-g-MA) 블렌드계의 상용화제로 maleic anhydride (MA)가 그래프트(graft)된 poly(styrene-b-ethylene-co-butylene-b-styrene) (SEBS-g-MA)를 첨가하여 블렌드의 고차구조에 미치는 영향을 small angle x-ray scattering, DSC 및 SEM을 이용하여 고찰하였다. SEBS-g-MA가 첨가된 시료는 첨가되지 않은 시료보다 PA6분상의 크기가 작았는데 이는 가공 또는 열처리 중 SEBS-g-MA의 무수말레산과 PA6의 아민 그룹(amine group) 사이에 반응이 일어나 PA6/PP-g-MA 계면에 PA6-SEBS-g-MA 그래프트 공중합체가 형성되어 이 공중합체가 상용화제로서 작용하여 계면장력을 안정화시켜 PA6 분산상 크기를 작게 한 것으로 추정되었다. 첨가된 SEBS-g-MA의 일부는 마이크로 상분리(Micro-phase separation)되어 미세 분산상으로 존재하게 되는데 그 크기는 첨가된 양이 많을수록, 저온보다 고온일수록 크다는 것이 관찰되었다. 미세 분산상 SEBS-g-MA는 PP-g-MA 연송상의 결정화도를 낮추는 반면, PA6 분산상의 결정화도는 증가시켰다. Effect of maleic anhydride grafted triblock copolymer of poly(styrene-b-ethylene-co-butylene-b-styrene) (SEBS-g-MA) on the morphology of the blends of polyamide 6 (PA6) and maleated polypropylene (PP-g-MA) was investigated by small angle x-ray scattering, differential scanning calorimeter and scanning electron microscopy. The size of the dispered PA6 decreased with addition of SEBS-g-MA. SEBS-g-MA reacted with the amine group of PA6 during the melt-compounding, and as a result, the copolymer, formed by interfacial reaction between PA6 and SEBS-g-MA, led to reduction in size of the dispersed PA6. SEBS-g-MA was partially microphase-separated to dispersion phase, and its size increased proportional to the amount of added SEBS-g-MA and increased temperature. The microphase-separated dispersion phase highly affected the crystallinity of the PP-g-MA matrix and PA6 dispersion.

단일상 Natural Polygonum Tinctroium 염료의 특성

최창용,양숙향,나재운 한국공업화학회 2004 응용화학 Vol.8 No.2

Indigo, as a blue pigment, has been known as one of the oldest natural dyes. Generally, natural dyes have moderate colors and are environmentally friendly, while harmful mordants must be used for fixing them and obtaining a full color range on fabrics and it is very hard to improve K/S of the dyeing and mordanting. In this study, single solid phase polygonum tinctroium dye was prepared by don- agitator and lyophilization and physicochemical characterization of polygoum tinctoria dye substance was investigated by UV/VIS spectrophotometer, TLC, DSC, FT-IR spectrophotometer, ¹H-NMR spectrophotometer, HPLC, MALDI-TOF mass, CHNS/O. Also cytotoxicity study of polygonum tinctroium dye was carried out MTT-assay.

졸-겔 법에 의해 제조된 광촉매 화합물의 항균 및 탈취 특성

공병기,최창용,나상권,나재운 한국공업화학회 2004 응용화학 Vol.8 No.1

Photocatalysis, which can be applied to get energy economically, to synthesis useful materials, and to remove environmentally harmful materials by transforming solar energy to chemical energy, has many advantages. In this study, photocatalystic compound was prepared by sol-gel technique for antimicrobial activity and deodorization. It showed that in case of deodorization, formaldehyde and ammonia were degraded by 98.3 and 97.1%, respectively. In addition, this compound gives the highest efficiency for disinfection of E. coli and S. aureus.

졸-겔법에 의한 이산화티타늄의 제조와 특성

공병기,나상권,최창용,나재운 한국공업화학회 2004 응용화학 Vol.8 No.2

Generally, photocatalysis can be applied to get energy economically, synthesize the useful materials, and remove environmentally harmful materials by transforming solar energy to chemical energy. Recently, the availability of photocatalysis has largely interested in the environment of Ubiquitous. Therefore, the study for photocatalysis has progressed by many investigators in domestic. In this study, titania sol was prepared by the sol-gel proess and characteristics of the products was investigated by TGA, XRD and SEM.

티타늄 졸에 의한 투명 박막의 제조 및 특성

공병기,나상권,최창용,나재운 한국공업화학회 2004 응용화학 Vol.8 No.2

Stable titania sols for preparation of TiO₂ thin films were synthesized from titanium tetra isopropoxide. TiO₂ thin films were prepared with by dipping the sols on the glass substrates, and the properties of the films were investigated with XRD, SEM and EDS.

폴리에틸렌테레프탈레이트의 용융거동에 미치는 기핵제의 영향 : ethylene terephtalate

나상권,공병기,최창용,나재운 한국공업화학회 2004 응용화학 Vol.8 No.1

Effect of nucleating agent on the melting behavior of PET was studied by DSC. The low crystallization temperature(T_(ch)) shifted to the low temperature and the nonisothermal crystallization peak temperatures(T_(cc)) shifted to the higher temperature as the concentration of the nucleating agent increased.

약물전달체를 위한 폴리에틸렌글리콜과 폴리카프로락톤을 이용한 나노입자

김태형,채수영,최창용,김동곤,김명열,나재운 한국공업화학회 2004 응용화학 Vol.8 No.2

The self-aggregation behavior and microscopic characteristics of the PEG-b-PCL copolymer self-aggregates, prepared by solvent evaporation method, were investigated by `H NMR, dynamic light scattering (DLS), and fluorescence spectroscopy. The PEG-PCL block copolymer formed nano-sized self-aggregates in an aqueous environment by intraand/or intermolecular association between hydrophobic PCL chains. Then, drug loading and its release behavior of clonazepam loaded PEG-b-PCL nanoparticles were investigated. The result revealed that hydrophobic-hydrophilic balances played a crucial role for drug loading and its release behaviors.

Polygoum Tinctoria와 합성 인디고 염료의 물리화학적 특성 비교

최창용,장미경,공병기,최혜영,나상권,이동병,양숙향,나재운 한국공업화학회 2002 응용화학 Vol.6 No.2

The natural dye substances appear to have a lot of benefits that enable the dyed materials to exhibit their natural colors. It may have a bit of a harmful influence on the human body itself, in comparison with the synthetic substances. It also causes hardly any environmental pollution because of the natural chemicals and costs much less to disposal. In this study was investigated physicochemical characterization of polygoum tinctoria dye substance and synthetic indigo. Calcium hydroxide was added into polygoum tinctoria leaves to precipitate dye substances and it was freezing dried into powder form. Characterizations of dye substances were investigated by UV/VIS spectrophotometer, TLC, DSC, TGA, HPLC, and MALDI-TOF Mass. Resultantly, polygoum tinctoria was confirmed that is consisted of two ingredients from these results.

Application of Nanofiltration Membrance

Nah, Jae-Woon,Shin, Sung-Euy,Park, Moon-Soo,Kim, Sun-Il,Kwun, Kyu-Hyuk,Yun, Young-Jae CHOSUN UNIVERSITY 1997 Basic Science and Engineering Vol.1 No.2

Nanofiltration membrane can be understood if one recalls that their properties lie between ultrafiltration membrane and reverse osmosis membrane. Most salts do not seem to foul the membrane, except at specific pH values where they precipitate and form scaling or some type of gel. The retentio of sucrose was neither affected much by the concentration nor by the presence of NaCl in small amounts. For sucrose the retention seemed to decrease comewhat with pressure. 0.1% NH₄Cl solutions were tested with the nanofiltration membrane at different pH values. The fluxes are the same as for NaCl at pH 3 and 5.7 but at pH 10 the flux increases significantly. Retention is the highest at pH 5.7 and 10 and similar or a bit less than the retention of NaCl. But at pH 3.0 the retention is very low. Maize starch containing small amounts of protein fouls more than potato starch. The investigation showed that nanofiltration membrane is good alternatives to reverse osmosis and ultrafiltration membrane for purification of waters containing mixtures of molecules of different sizes and charges.

Drug Release from Nanoparticles of Poly(DL-lactide-co-glycolide)

Nah, Jae Woon,Jeong, Young Il,Koh, Jae Joon 한국화학공학회 2000 Korean Journal of Chemical Engineering Vol.17 No.2

Nanoparticles of poly(DL-lactide-co-glycolide) (PLGA) were prepared by dialysis method without surfactant. The size of PLGA nanoparticles prepared from dimethylacetamide (DMAc), dimethylformamide (DMF), and dimethylsulfoxide (DMSO) as an initial solvent was smaller than that of acetone or 1,4-dioxane. Selected initial solvent used to dissolve the copolymer significantly affects the size of nanoparticles. Also, the size of PLGA nanoparticles was changed according to the copolymer composition. It was shown that PLGA nanoparticles have spherical shapes from the results of scanning electron microscope (SEM) and transmission electron microscope (TEM) observations. From these results was shown the potential that the PLGA nanoparticles could be formed successively by dialysis method without surfactant. The drug-loading contents were also dependent on the copolymer composition and initial feeding amount of the drug. The greater lactide ratio on the copolymer composition led to higher drug loading contents. Also, the higher the initial feeding amount of drug, the higher the drug loading contents. Clonazepam (CNZ) was used as a model drug. CNZ was slowly released in higher lactide ratio in the copolymer composition and in the higher drug loading contents.