• Bulletin of the Korean Chemical Society
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• 제16권12호
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• pp.1167-1172
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• 1995

A coverage of about 1 μm-sized pores of a membrane filter by four monolayers of maleic acids copolymers and poly(allylamine) (PAA) was attained by Langmuir-Blodgett (LB) technique through a covalent cross-linking followed a polyion complexation at the air-water interface. The copolymers were prepared to have side chains of hydrocarbon tail, carboxyl, and/or oligoether in the repeat unit. The surface pressure-area isotherms showed that the monolayers on an aqueous PAA have more expanded area than on pure water. The monolayers were transferable on a calcium fluoride substrate and a fluorocarbon membrane filter as Y deposition type, and the resulting LB films were characterized by FT-IR spectroscopy and scanning electron microscopy. A polymer network produced through interchain amide formation was confirmed in as-deposited films. The films were heat-treated in order to complete the cross-linking. SEM observation of the heat-treated film on a porous membrane filter showed that the four layer film was sufficiently stable to cover the filter pore of about 1 μm. Immersion of the film in water or in chloroform did not cause any change in its appearance on SEM and in FT-IR spectra.

• Bulletin of the Korean Chemical Society
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• 제17권7호
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• pp.607-612
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• 1996

A series of new NLO-active poly(4-nitrophenylallylamine) derivatives was synthesized by the nucleophilic substitution reaction of several substituted 4-nitrohalobenzenes and poly(allylamine hydrochloride). All polymers obtained were amorphous and their glass transition temperatures (Tg) were observed around 148-160 ℃. For each of these polymers, their specific Tg values were dependent on characteristic electronic structures. UV-visible absorption spectra showed maximum absorption intensity at 355-393 nm for π-π* transition of alkylaminonitrophenyl groups. The χ(2)value of poly(4-nitrophenylallylamine), as determined by the second harmonic generation at 1064 nm, for a thin polymer film poled at an elevated temperature, was 1.4x10-8esu. The third-order NLO properties of poly(4-nitrophenylallylamine) derivatives were evaluated through measurement of degenerate four-wave mixing technique and χ(3) coefficient in the range of 2.7~3.2x10-12 esu at 602 nm was found with 400 fs laser pulses.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 C
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• pp.1196-1198
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• 1995

In this paper, stability improvement of fragile LB films was attempted by monolayers at the air-water interface and crosslinking of the resulting LB films. The spreading polymers were synthesized by radical copolymerization of monoalkyl with oligoethyleneglycol methyl ether, and poly(allylamine) was employed as the subphase polymer. The monolayer properties have been studied by the surface pressure-area($\pi$-A) isotherms. Interaction between polymers and metal ions at the air-water interface and in their LB films were investigated. From the FT-IR(Reflection and Transmission) spectra, the formation of carboxylate ions and the relative orientation of the side chains could be confined. The monolayers were transferable on various substrates, and the resulting LB films were characterized by SEM and VIS-UV absorbance.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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• pp.59.1-59.1
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• 2015

In the Linford group at Brigham Young University we have recently developed three new sets of materials for three different areas of separations science: thin layer chromatography (TLC), high performance liquid chromatography (HPLC), and solid phase microextraction (SPME). First, via microfabrication we have grown patterned carbon nanotube (CNT) forests on planar substrates that we have infiltrated with inorganic materials such as silicon nitride. The coatings on the CNTs are conformal and typically deposited in a process like low pressure chemical vapor deposition. The resulting materials have high surface areas, are porous, and function as effective separation devices, where separations on our new TLC plates are typically significantly faster than on conventional devices. Second, we used the layer-by-layer (electrostatically driven) deposition of poly (allylamine) and nanodiamond onto carbonized poly (divinylbenzene) microspheres to create superficially porous particles for HPLC. Many interesting classes of molecules have been separated with these particles, including various cannabinoids, pesticides, tricyclic antidepressants, etc. Third, we have developed new materials for SPME by sputtering silicon onto cylindrical fiber substrates in a way that creates shadowing of the incoming flux so that materials with high porosity are obtained. These materials are currently outperforming their commercial counterparts. Throughout this work, the new materials we have made have been characterized by X-ray photoelectron spectroscopy, time-of-flight secondary ion mass spectrometry, scanning electron microscopy, transmission electron microscopy, etc.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1995년도 춘계학술대회 논문집
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• pp.220-223
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• 1995

Stable polyion-complexed polymeric monolayrers were prepared by spreading perfluoroalkyl monomaleatd copolymers. C$_2$F$\_$8/MA-VE$_2$ and C$_2$F$\_$8/Mv-VE$_3$ on aqueous poly(allylamine) subphase. The monolayer properties have been studied by the surface pressure-area($\pi$-A) isotherms. The C$_2$F$\_$8/MA-VE$_3$containing longer oligoethyleneglycol pendant showed more expaned monolayer phase than the C$_2$F$\_$8/MA-VE$_2$ The polyion-complexed monolayers were transferable on various substrates, and the resulting Langmuir-Blodgett(LB) films were characterized b ET-IR spectroscopy and scanning electron microscopy(SEM) Two-dimensional crosslinking to from a polymer network was achieved by amide formation through heat treatment under vacuum with concurrent removel of perfluoroalkyl tails. SEM observation of this film ona porous membrane filter showed that the four layer film was sufficiently stable to cover the filter pore size of 0.1$\mu\textrm{m}$. The C$_2$F$\_$8/MA-VE$_3$revealed better covering capability than the C$_2$F$\_$8/MA-VE$_2$Immersion of this film in water or in benzend did not cause any change in its appearance and in FT-IR spectra.

• Korea-Australia Rheology Journal
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• 제15권1호
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• pp.1-7
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• 2003

A new method is introduced to build up organic/organic multilayer films composed of cationic poly(allylamine hydrochloride) (PAH) and negatively charged poly (sodium 4-styrenesulfonate) (PSS) using the spinning process. The adsorption process is governed by both the viscous force induced by fast solvent elimination and the electrostatic interaction between oppositely charged species. On the other hand, the centrifugal and air shear forces applied by the spinning process significantly enhances desorption of weakly bound polyelectrolyte chains and also induce the planarization of the adsorbed polyelectrolyte layer. The film thickness per bilayer adsorbed by the conventional dipping process and the spinning process was found to be about 4 ${\AA}$ and 24 ${\AA}$, respectively. The surface of the multilayer films prepared with the spinning process is quite homogeneous and smooth. Also, a new approach to create multilayer ultrathin films with well-defined micropatterns in a short process time is Introduced. To achieve such micropatterns with high line resolution in organic multilayer films, microfluidic channels were combined with the convective self-assembly process employing both hydrogen bonding and electrostatic intermolecular interactions. The channels were initially filled with polymer solution by capillary pressure and the residual solution was then removed by the .spinning process.

• 공업화학
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• 제2권4호
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• pp.348-355
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• 1991

Hexamethylcyclotrisiloxane($D_3$), tetramethylcyclotetrasiloxane(TMCTS)을 공중합 시켜 Si-H 결합을 함유한 polysiloxane 공중합체를 합성하고 allylamine과 반응시켜 amino 기를 도입시킨후 naphthoquinone-1,2-diazide-5-sulfonyl chloride 와 반응시켜 naphthoquinone-1,2-diazide-5-sulfonyl 기가 도입된 polysiloxane을 합성하였다. 생성 공중합체의 열적특성을 측정한 결과, 열분해온도는 $360{\sim}450^{\circ}C$ 정도였으며 또한 감광특성은 backbone 수지의 분자량이나 증감제의 종류에 따라 영향을 받았다. Sensitivity는 $50{\sim}120mJ/cm^2$였고 contrast(${\gamma}$)는 1.4~2.1였으며 backbone 수지의 분자량이 증가함에 따라 약간 감소하였다.

• Korean Chemical Engineering Research
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• 제55권3호
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• pp.287-295
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• 2017

Using nanotechnology, magnetic nanoparticles of iron oxide were produced via co-precipitation method and followed modification with organic compounds. In the next step, functionalized monomer was provided via coupling ${\beta}$-cyclodextrine and allylamine onto modified magnetic nanoparticles. These nanoparticles were used to establish the adsorption rate of celecoxib. Magnetic nanoparticles are modified by (3-mercaptopropyl)trimethoxysilane. Nano-adsorbent was characterized by analytical and spectroscopic methods, such as Fourier transform infrared spectroscopy, elemental analysis, thermo-gravimetric analysis, and transmission electron microscopy (TEM). Laboratory parameters, such as the kinetics of adsorption isotherms, pH, reaction temperature and capacity were optimized. Finally, by using this nano-adsorbent in the optimized condition, extraction of celecoxib from biological samples as urine, drug matrix and blood plasma was carried out by high performance liquid chromatography with sensitivity and high accuracy.

• 약학회지
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• 제41권2호
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• pp.187-194
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• 1997

For the development of antifungal agents, modification of naftifine which exhibits significant antimycotic activity was performed by replacing the naphthalene ring of it to hete ro cyclic rings such as morpholine. benzothiazole, piperidine and pyridine derivatives. The synthesized compounds were tested in vitro antifungal activity against five different fungi with naftifine as a comparative antimycotic molecule. From the biological evaluation two compounds, (E)-N-(3-phenyl-2-propenyl)-N-(4-piperidinylmethyl)amine(3d) and (E)-N-(3-phenyl-2-propenyl)-N-(3-pyridylmethyl)amine(3f) showed relatively noticeable activity(MIC=50${\mu}g$/ml). On the other hand, the other compounds had no activity.

• 한국염색가공학회지
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• 제12권1호
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• pp.61-67
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• 2000

This study was carried out to develope antimicrobial artificial suede by coating with water soluble polyurethane resin and the copolymer of N,N'-dialkyl-N,N'-dialkyl ammonium chloride (DADAAC) and acrylamide as a antimicrobial additve. The copolymer of DADAAC and acrylamide was synthesized by free radical initiation and intra-intermolecular propagation, and the prepared copolymers had sufficient compatibility with water soluble polyurethane resin. The MIC values of the prepared copolymers and antimicrobial characteristics of the artificial suede coated by polyurethane were evaluated. With the increase in the proportion of DADAAC, which is antimicrobially active part in the DADAAC/acrylamide copolymers, the MIC value becomes lower. The MIC value of DADAAC-AA (1 : 1) copolymer is below 30 ppm against S. aureus, and below 90 ppm against K pneumoniae. The artificial suede coated by water soluble polyurethane resin with 1.0% owl concentration of DADAAC/acrylamide copolymer has good antimicrobial fastness as to show colony reduction of above 90% and 80% against S. aureus and K. pneumoniae respectively in the shake flask test after 10 times of washing, and above 95% and 85% after 10 times of dry-cleaning. The elastic recovery of coated suede fabric is not affected up to 1.0% owf concentration of DADAAC-AA copolymer in the polyurethane coating.