• Bulletin of the Korean Chemical Society
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• 제25권8호
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• pp.1225-1230
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• 2004

The stability of fluoroalkyl groups as a pendent on the phenyl ring was measured in vitro using rat hepatic microsomes and human serum to predict their in vivo stabilities. We have prepared three [$^{18}F$]fluoroalkyl-biphenyls as the model compounds of fluoroalkyl aromatic compounds to compare the in vitro stabilities. In addition, in vitro stabilities were measured separately using rat hepatic microsomes and human serum at $37^{\circ}C$. Fluoroethylbiphenyl had similar or slightly superior stability to fluoropropylbiphenyl and these two compounds were much more stable than fluoromethylbiphenyl in vitro.

• 폴리머
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• 제29권5호
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• pp.463-467
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• 2005

Fluoroalkyl methacrylate, 아크릴산, 2-hydroxyethyl methacrylate(HEMA)를 공중합한 불소화 아크릴계 이온성 고분자로 제조한 이온성 고분자-백금 복합재료(IPMC)의 구동력을 증대시키기 위하여, HEMA의 OH기를 1,3-diethoxy-1,1,3,3-tetramethyldisiloxane으로 가교하였다. 가교반응에 의하여 IPMC의 수분흡수가 감소하면서, 기계적 강도, 구동력이 증가함을 관찰하였다. 그러나 IPMC의 구동성, 즉 외부 전위에 의한 변위와 전류량은 가교에 의해 감소하였다.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 봄 학술발표회 논문집
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• pp.327-328
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• 2003

최근, 가정 안까지 고속광통신망이 구축되면서 폴리머광섬유 (polymer optical fiber, POF)에 대한 관심이 매우 증가하고 있다[l,2] POF는 빛을 전송하는 코어층과 내부전반사를 유도하면서 코어를 보호하는 클래드 층으로 구성되어 있다. 빛을 직접 전송하지 않으나 POF가 최적의 성능을 보이기 위해서는 적절한 클래드 선택이 중요하다. 그러나 PVDF/PMMA 블렌드, fluoroacrylate, VDF-HFP 공중합체 등이 클래드용 재료로 사용되고 있다는 사실만이 알려져 있을 뿐 보다 자세한 정보는 보고된 바 없다. (중략)

• 한국염색가공학회지
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• 제24권3호
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• pp.173-179
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• 2012

Silk fabric treated with fluorocarbon resins (Asahi Guard AG-7005 and AG-E061) were washed and subsequently heat treated varying the washing cycles and the temperature. After the processing, the water and oil repellencies, and contact angle to water were evaluated. The water and oil repellencies decreased by the washing and recovered by following heat treatment. Also ESCA measurement was carried out to investigate the surface chemical composition of the treated fiber. The $F_1s$ intensity of the treated fabric decreased by the washing and recovered by the subsequent heat treatment. On the other hand, the $O_1s$ intensity increased by the washing and decreased by following heat treatment. From the results, it is clear that change of the water and oil repellencies of the silk fabric treated with fluorocarbon resin occurred by the washing and subsequent heat treatment. Considering a change of the water repellency of the silk fabric treated with fluorocarbon resin, it seems likely that the fluoroalkyl group of the fluorocarbon resin rotates from surface to inside of the fiber by the washing to adapt to the hydrophilic circumstance, and the orientation of the fluoroalkyl groups of the resin disturbed by the washing recovers the orientation to the fiber surface after the subsequent heat treatment.

• 폴리머
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• 제29권4호
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• pp.380-384
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• 2005

Sodium montmoillonite 혹은 sodium montmorillonite가 삽입된 macromer의 존재 하에서 fluoroalkyl methacrylate와 아크릴산을 라디칼 공중합하여 불소화 아크릴계 이온성 고분자/sodium montmorillonite 복합재료를 제조하고, 이들의 X-선 회절 특성, 인장물성, 수분흡수율 등 물리적 성질을 조사하였다. 또, 이들을 이용하여 이온성 고분자-백금 복합재료(IPMC)를 제조하여 수 볼트의 외부 전위에 의한 전류 흐름 및 변위 거동을 측정한 결과, sodium montmorillonite가 이온의 이동을 방해하여 전류 및 변위량의 감소를 초래함을 관찰하였다.

• Macromolecular Research
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• 제12권6호
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• pp.593-597
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• 2004

A new ionomeric polymer-metal composite (IPMC) was prepared using a cast membrane of acrylic copolymer, which was synthesized by radical copolymerization of fluoroalkyl acrylate and acrylic acid (AA). To examine its performance as a new electroactive polymer, the current and displacement responses to a step voltage applied across the IPMC were measured. The largest responses were observed when the AA content in the copolymer was $10.6\;wt\%$.

• 한국염색가공학회지
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• 제25권1호
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• pp.30-36
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• 2013

Swelling and subsequent deformation of membranes by water wetting are regarded as a prime drawback of hydrophilic polyurethane breathable film. Fluoroalkylated surface was prepared by reacting the film with hexamethylene diisocyanate(HDI) and 2-perfluorohexyl ethanol. IR spectra and XPS results showed that the fluoroalkyl group was successfully introduced to the film surface with hexamethylene linkage. Water contact angle was increased from $68.7^{\circ}$ up to $144.2^{\circ}$ with the degree of fluoroalkylation. Decrease in water-vapor permeability was minimized even for the film of highest fluoroalkylation.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.184-184
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• 2006

We have succeeded in the preparation of high molecular weight polybenzimidazoles by solution polycondensation of 3,3'-diaminobenzidine tetrahydrochloride with isophthalic acid, terephthalic acid, or with their derivatives using polyphosphoric acid both as solvent and as condensing agent. Also, we modified phosphoric acid into fluoroalkyl-phosphonic acids[F-PA]. The main reasons are as follows, first of all F-PAs are stronger acids than PA and alkylphosphonic acids which should promote proton hopping and transport. In addition, F-PA has weaker adsorption onto Pt which help to prevent electrocatalyst poisoning and promote higher oxygen reduction activity. The ionic conductivity of 85%-H3PO4 doped membranes show $10^{-2}\;Scm^{-1}\;to\;3{\times}10^{-2}\;Scm^{-1}\;at\;150^{\circ}C$ MEA with 2 %-added electrolyte shows slightly higher cell voltage than the others.

• Bulletin of the Korean Chemical Society
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• 제21권4호
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• pp.441-445
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• 2000

A new series of three ring type liquid crystalline compounds containing partially fluorinated alkenyl or alkyl side chains together with fluorine substituted cyclohexylbiphenyls were designed and synthesized in this study. The structures of synthe sized compounds were established by 1 H, 13 C and 19 F NMR spectroscopy. The phase transition temperatures of fluorinated liquid crystalline compounds were determined by cross-polarizing mi-croscopy equipped withhot stage. All compounds were found to have nematic liquid crystalline phase with rel-atively low phase transition temperature and wide liquid crystalline temperature range. The dependence of phase transition temperatures on the chainlength falls into three categories; (a) decreasing transition tempera-tures for 4-fluoro-4'-[4-fluoro-4-(1-fluoroalkyl)cyclohexyl]biphenyl (15) series, (b) higher transition tempera-tures for odd numbered chains for 4-fluoro-4'-[4-fluoro-4-(1-fluoroalk-1-enyl)cyclohexyl]biphenyl (14) series, (c) higher transition temperatures for even numbered chains for 4-[4-(1,2-difluoroalk-1-enyl)-4-fluorocyclo-hexyl]-4'-fluorobiphenyl (16) series.

• 폴리머
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• 제27권4호
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• pp.364-369
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• 2003

보호된 이소시아네이트기를 가지는 발수성 아크릴계 고분자를 합성하기 위해 개시제로 $\alpha$,$\alpha$'-아조비스이소부틸로니트릴을 사용하여 2-fluorohexylethyl acrylate (FA)와 2-(o-(1'-methylpropylidenamino)carboxyl amino)ethyl methacrylate(MEM)를 몰비를 변화시키면서 메틸 에틸 케톤 중에서 공중합하였다. 합성한 공중합체중의 MEM과 FA의 함량을 NMR로 분석하였다. 이 결과를 이용하여 Kelen-Tudos 플로트에 의해 MEM (1)과 FA (2)의 단량체 반응성비를 구하였다. 그 결과 r$_{1}$＝1.59였고 r$_{2}$＝0.50였다. 이들 고분자의 수평균분자량은 39400에서 72400사이에 있었고 다분산 지수는 대략 1.5정도였다. 그 고분자중의 보호된 이소시아네이트기는 15$0^{\circ}C$ 이상의 온도에서 이소시아네이트기로 재생되었다. FA를 65 ㏖% 함유하는 고분자의 물에 대한 접촉각은 95$^{\circ}$정도였다.