• 대한화학회지
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• 제26권4호
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• pp.235-246
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• 1982

본 연구에서는 자유라디칼 메카니즘에 의한 N-acetyl ${\alpha}$-aminoacrylic acid의 단독중합 반응속도와 혼성중합 반응성을 연구하였으며, DMF 용매를 사용하여 $60^{\circ}C$에서 단독중합 시켰을 때의 중합속도 ($R_p$)는 단위체 농도 [M]와 개시제 농도 [I]에 대하여 $R_p$ = $k_p[M]^{0.97}[I]^{0.59}$의 관계를 나타내었다. 또한 이 단위체의 단독중합 총괄 활성화 에너지는 25.2 kcal/mole이었다. N-acetyl ${\alpha}$-aminoacrylic acid를 아크릴산 및 스티렌 단위체와 혼성중합 시켰을 때의 단위체 반응성비는 아래와 같았다. $r_1$(N-acetyl ${\alpha}$-aminoacrylic acid) = 0.49, $r_2$(acrylic acid) = 1.41; $r_1$(N-acetyl ${\alpha}$-aminoacrylic acid) = 0.44, $r_2$(styrene) = 0.91. Alfrey-Price 식을 이용하여 계산한 N-acetyl ${\alpha}$-aminoacrylic acid의 Q와 e값은 두 경우 모두 Q=0.51, e=0.16이었다. 단독중합체 및 혼성중합체들의 열적성질을 DTA 및 TGA법으로 분석하여 비교하여 보았다.

• Bulletin of the Korean Chemical Society
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• 제7권6호
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• pp.472-477
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• 1986

The reaction of (E)- or (Z)-1-alkenylmercuric chlorides with acrylic acid derivatives in the presence of 10 mol% of lithium trichloropalladate ($LiPdCl_3$) and an equimolar amount of cupric chloride, as a reoxidant for the palladium, in acetonitrile at room temperature gave the corresponding (E,E)- or (E,Z)-2,4-dienoic acid derivatives stereospecifically in moderate to good yields. The reaction of (E)- or (Z)-3-chloromercuripropenoic acid with olefins under the reaction condintion described above similarly gave good yields of (E,E)- or (Z,E)-2,4-dienoic acids stereospecifically. A side reaction, the homocoupling of alkenylmercuric chlorides, could be minimized by employing the condition described above. However, in the reaction of 3-chloromercuripropenoic acid with olefins under the present condition, the homocoupled side reaction product was not produced.

• 접착 및 계면
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• 제6권1호
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• pp.11-18
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• 2005

심물질(core)이 상변화물질(Phase Change Material, PCM)이고, 벽물질(shell)이 멜라민 포름알데히드 수지인 마이크로 캡슐을 제조하였다. 제조된 캡슐의 크기가 아크릴 코팅(acrylic coating)의 물성에 미치는 영향을 알아보기 위하여 PCM 캡슐의 크기를 $3{\sim}25{\mu}m$로 조절하여 제조하였다. 제조된 캡슐의 심물질 함량과 캡슐의 크기는 DSC와 SEM을 이용하여 확인하였다. 아크릴 에멀젼은 butyl acrylate, methyl metacrylate와 acrylic acid를 공중합하여 제조하였다. 제조된 PCM 캡슐과 아크릴 에멀젼을 혼합하여 필름으로 제조하였다. 캡슐의 크기가 작을수록 아크릴 코팅 필름 내에 캡슐이 잘 분산됨을 확인할 수 있었고, 캡슐의 크기가 클수록 필름 표면이 매끄럽지 않음을 관찰할 수 있었다. 필름의 수분 흡수율은 PCM 캡슐의 크기에 큰 영향을 받지 않았지만 필름의 인장 강도와 신율은 캡슐의 크기가 작을수록 증가하였다.

• 접착 및 계면
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• 제14권1호
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• pp.43-48
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• 2013

압력감응성 아크릴 점착제의 물성은 가교를 위한 관능성그룹을 가진 단량체를 이용하여 쉽게 물성을 조절할 수 있다. 본 연구에서는 두개의 다른 가교제, isocyanate 및 epoxy형 가교제에 따른 아크릴 점착제의 가교특성과 물성을 연구하였다. 2-Ethylhexyl acrylate, acrylic acid (AA)와 2-hydroxyethyl methacrylate를 주 단량체로 하여 이소시아네이트 또는 에폭시형 가교제로 가교한 점착제의 박리점착 특성, 볼텍, 유지력 및 수축성을 고찰하였다. 점착특성은 AA함량 증가와 더불어 증가하였고 가교점이 많고 ether와 같은 유연한 결합을 생성하는 에폭시형 가교제에서 우수한 물성을 나타내었다.

• 폴리머
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• 제28권3호
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• pp.273-280
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• 2004

고형분 80%인 아크릴수지 (에틸 메타크릴레이트-2-히드록시프로필 메타크릴레이트-노르말부틸 아크릴레이트-아크릴산 : EHBC)를 합성한 후 이를 헥사메틸렌 디이소시아네이트-뷰렛 경화제로서 상온경화시켜 고 고형분 도료 (에틸 메타크릴레이트-2-히드록시프로필 메타크릴레이트-노르말부틸 아크릴레이트-아즈릴산/헥사메틸렌 디이소시아네이트-뷰렛 : EHBCN)를 제조하였다. 진동자법에 의한 점탄성 측정에서 제조된 도료인 EHBCN-4 (EHBC-4 정적 $T_{g}$ $0^{\circ}C$)와 EHBCN-7 (EHBC-7 : 정적 $T_{g}$ 3$0^{\circ}C$)의 경화시간은 6.2시간과 4.5시간으로, 또한 경화된 도막의 동적 $T_{g}$ 는 $14^{\circ}C$ 와 $39^{\circ}C$로 각각 나타났다. 도막 물성 중 접착력과 굴곡성은 카프로락톤 아크릴레이트 단량체 성분이 함유된 EHBCN쪽의 물성이 현저히 좋게 나타나, 카프로락톤 아크릴레이트 성분이 접착력과 굴곡성을 증진시켰음이 입증되었다.

• Bulletin of the Korean Chemical Society
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• 제7권1호
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• pp.42-45
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• 1986

Quenching of excimer fluorescence from polystyrene-acrylic acid copolymers containing $Eu^{3+}$ has been studied in tetrahydrofuran solution using simple aromatic hydrocarbons as quenchers under steady-state conditions. Aromatic hydrocarbons quenched collisionally the excimer fluorescence and their rate constants of quenching were determined. The magnitude of quenching constant is interpreted in terms of the cube root of the molar volume of quencher. Cycloalkanes were not effective in quenching the excimer fluorescence possibly due to different solubility characteristics from aromatic hydrocarbons.

• Bulletin of the Korean Chemical Society
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• 제6권3호
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• pp.164-168
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• 1985

The fluorescence emission of polystyrene-acrylic acid copolymers containing $Eu^{3+}$ in tetrahydrofuran solution was investigated by spectrofluorimetry. The excimer emission increased linearly with the polymer concentration up to approximately $5{\times}10^{-3}$M. Benzene and toluene collisionally quenched the excimer fluorescence and thier rate constants of quenching were determined. Quenching efficiencies decreased in the order: naphthalene > toluene > benzene. Analyses of Rayleigh scattering and europium emission showed no measurable structural changes observed under the experimental conditions.

• 한국신뢰성학회지:신뢰성응용연구
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• 제17권1호
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• pp.72-77
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• 2017

Purpose: The electrochemical corrosion behavior of tin oxide film coated on PET substrates has been studied under varying concentrations of acrylic acid to investigate possible corrosion in contact with the acidic environment. Method: Potentiodynamic test was performed for a commercial ITO/PET film in 0.1, 0.3, and 0.5 M of acrylic acid. The surface morphology was analyzed by scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). Results: Potentiodynamic test results showed an increase in Icorr and decrease in Ecorr value with increasing concentration of acid. Microscopic evaluation suggested the presence of certain deep cracks on the surface of the film in addition with a severe acidic attack. Conclusion: Exposure of ITO to acrylic acid resulted in the stress corrosion cracking of ITO film due to the mechanical mismatch between brittle inorganic ITO fim and a compliant organic PET substrate leading to the subsequent failure of the film.

• Bulletin of the Korean Chemical Society
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• 제35권1호
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• pp.182-188
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• 2014

Three new transition metal complexes based on Ozagrel $[Cu(Ozagrel)]_n$ (1), $[Zn(Ozagrel)(Cl)]_n$ (2), ${[Mn_2-(Ozagrel)(1,4-ndc)_2]{\cdot}(H_2O)}_n$ (3), (Ozagrel = 3-(4-((1H-imidazol-1-yl)methyl)phenyl)acrylic acid; 1,4-ndc = 1,4-Naphthalenedicarboxylic acid) have been hydrothermally synthesized and characterized by elemental analyse, IR, TG, PXRD, electrochemical analysis and single crystal X-ray diffraction. X-ray structure analysis reveals that 1 and 3 are 3D coordination polymers, while complex 2 is a two-dimensional network polymer, the 2D layers are further packed into 3D supramolecular architectures that are connected through hydrogen bonds. The electrochemistry of 1-3 was studied by cyclic voltammetry in methanol and water using a glassy carbon working electrode. Also, thermal decomposition process and powder X-ray diffraction of complexes were investigated.

• Membrane and Water Treatment
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• 제7권2호
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• pp.101-113
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• 2016

In this study, to improve the water flux of porous hydrophobic membranes, various water-soluble polymers including neutral, cationic and anionic polymers were adsorbed using 'salting-out' method. The adsorbed hydrophobic membrane surfaces were characterized mainly via the measurements of contact angles and scanning electron microscopy (SEM) images. To enhance the durability of the modified membranes, the water-soluble polymers such poly(vinyl alcohol) (PVA) were crosslinked with glutaraldehyde (GA) and found to be resistant for more than 2 months in vigorously stirred water. The water flux was much more increased when the ionic polymers used as the coating materials rather than the neutral polymer and in this case, about 70% of $0.31L/m^2{\cdot}h$ (LMH) to 0.50 LMH was increased when 300 mg/L of polyacrylamide (PAAm) was used as the coating agents. Among the cationic coating polymers such as poly(styrene sulfonic acid-co-maleic acid) (PSSA_MA), poly(acrylic acid-comaleic acid) (PAM) and poly(acrylic acid) (PAA), PSSA_MA was found to be the best in terms of contact angle and water flux. In the case of PSSA_MA, the water flux was enhanced about 80%. The low concentration of the coating solution was better to hydrophilize while the high concentration inclined to block the pores on the membrane surfaces. The best coating condition was found: (1) coating concentration 150 to 300 mg/L, (2) ionic strength 0.15, (3) coating time 20 min.