• Magazine of the Korea Concrete Institute
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• v.7 no.2
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• pp.175-182
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• 1995

Styrene-Maleic anhydride copolymer (SMA) was prepared by the radical copolmerization of styrene and maleic anhydride using ${\alpha}-{\alpha}'$ azobis(isobutyronitrile) as an initiatrr. SMA was further reacted with m-amino phenol to obtain aminophenol-substituted SMR (mSMA). Sulfonated SMA and mSMA were also prepared by the reaction of copolymers with sulfuric acid The copolyniers were characterized by infrared spectroscopy. It was found from the results of elemental analysis that the substitution degree of aminophenol in the mSMR is 44% and the degree is lowered to 35% after sulfonation. The percentage of copolymers adsorbed on the surface of cement particles was increased with a decrease of added copolymers. While, the arnourit of sulfonated SMA absorbed on the surface of cement particles was larger than that of the sulfonated mSMA The copolymers synthesized in this study are probably expected as a high range water reducer for coiicxte.

• Journal of the Microelectronics and Packaging Society
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• v.10 no.4
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• pp.21-27
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• 2003

The copolymers with various composition of methyl methacrylate (MMA), ethyl methacrylate (EMA), methacrylic acid (MA) and hydroxyethyl methacrylate (HEMA) were synthesized for capacitive humidity sensitive materials. The capacitive humidity sensor consisted of a polymethacrylate film coated on both sides with gold electrode. Capacitance versus relative humidity increased with HEMA content in the copolymer. In the case of self-crosslinkable MMA/MA/HEHA= 40/10/10, the average capacitance at 30%RH, 60%RH and 90%RH are 102, 134 and 166 pF, respectively. And also, the hysteresis, temperature cycle and long-term stability were evaluated as a capacitance humidity sensor.

• Journal of the Korean Chemical Society
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• v.31 no.3
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• pp.287-291
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• 1987

The composite mole fraction of monomers in PVA-PVFAc copolymer could be calculated from the analysis of trifluoroacetyl group by the pyrolysis gas chromatography without breaking of C-F bonds in polymer. A linearity between trifluoroacetyl peak areas in pyrogram and sample weights was obtained within the range below 3mg. The data of trifluoroacetyl contents derived from gas chromatogram of copolymers with various D.S. were in good agreement with results by the Specific Ionmeter.

• Applied Chemistry for Engineering
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• v.18 no.2
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• pp.121-125
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• 2007

Siloxane monomer and oligomer were introduced to n-butyl acrylate and methyl methacrylate copolymer for improvement of water resistance and tactile sensation of acryl-type emulsion. Terpolymerimerization of n-butylacrylate, methyl methacrylate and siloxane monomer or oligomer was carried out in aqueous solution. The glass transition temperature (Tg) of terpolymer decreased with increasing siloxane monomer, however, the Tg of terpolymer increased with increasing siloxane oligomer due to the crosslinking of acrylated end group. The adhesion property and surface energy of the obtained terpolymer decreased with introducing siloxane monomer or oligomer in terpolymer. Decrement of tack and surface energy means the enhancement of water resistance and tactile sensation of the emulsion.

• New & Renewable Energy
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• v.2 no.4 s.8
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• pp.46-55
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• 2006

본 연구는 불소그룹을 함유한 술폰화된 아릴렌에테르계 블록 공중합체 고분자 전해질막의 제조 및 연료전지 특성에 관한 것이다. 이러한 불소그룹을 함유한 술폰화된 아랄렌에테르계 블록 공중합체를 제조하기 위하여 양말단에 불소계 비닐기를 가지면서, 고분자 전환시 상온에서 술폰화 가능한 biphenyl계 단량체와 술폰화가 불가능한 sulfonyl계 단량체를 각각 합성하였다. Biphenyl계 단량체로 부터 올리고머를 합성한 후 sulfonyl계 단량체와 열적 고리화 부가중합을 하여 다양한 몰조성을 갖는 일련의 perfluorocyclobutane(PFCB)기를 포함하는 블록 공중합체를 제조하였다. 제조된 블록 공중합체를 상온에서 술폰화제인 chlorosulfonic acid(CSA)를 이용하여 후술폰화시켜 강산 이온기인 sulfonic acid를 biphenyl계 올리고머 부분에 선택적으로 도입하였다. 이렇게 제조된 술폰화된 고분자를 제막한 후 연료전지 특성을 Nafion-115와 비교하였다. 술폰화가 되는 올리고머 블록의 비율 증가에 따라 이온교환능력 (IEC)이 증가하였고 , 그에 따른 팽윤도 역시 증가하는 것을 보였다. 술폰화된 고분자들은 건조 및 습윤 상태에서도 기계적 강도가 우수하였다. 최적화된 술폰화 블록 고분자(S-2) 를 대상으로 membrane electrolyte assembly(MEA) 를 제조하여 연료전지 초기성능을 측정한 결과 Nafion-112와 유사한 전기화학적 성능을 나타내었다.

• Applied Chemistry for Engineering
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• v.7 no.4
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• pp.679-690
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• 1996

Acrylic copolymer was synthesized from 2-dimethylaminoethyl methacrylate and alkylmethacrylate containing long chain hydrocarbon group. To facilitate emulsification in water, acrylic copolymer was treated with acetic acid, and therefore acetated acrylic copolymer was produced. Acetated acrylic copolymer was perfectly emulsified in water and showed increased emulsion stability. Polymer as a cement dispersion agent(PDCM-PSD) was prepared by blending the newly synthesized acetates acrylic copolymer with sodium gluconate, oleic acid, and triethanolamine. The applicability of the blended polymer was examined, and it was found that the effects of dispersion and water-proof(0.3~0.5) were excellent.

• Polymer(Korea)
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• v.24 no.3
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• pp.306-313
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• 2000

Polycaprolactone (PCL) macromer containing terminal methacrylate group was synthesized by ring-opening polymerization. The number average molecular weight of PCL macromer was 11600 g/mole and polydispersity index was 1.09. The synthesized PCL macromer was copolymerized with styrene by stable free radical polymerization using 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO), benzoyl peroxide, and well-defined poly(styrene-g-caprolactone)s were synthesized. The synthesized copolymers was characterized by $^1$H-NMR and gel permeation chromatography equipped with multiangle laser light scattering detector. Thermal properties of graft copolymers were investigated by DSC.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.41-44
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• 2002

블렌딩이나 공중합체의 합성은 한가지 또는 모든 구성성분 고분자의 단점을 보완하면서 효과적인 물성 발현을 위해 연구되어 왔다. 특히 방향족 폴리에스테르계 고분자들 사이에서는 PET/PEN, PEN/PHN, PBT/PBN, 또는 PET/PBT 등의 공중합체가 보고되고 있다[1-3]. 한편, poly(trimethylene terephthalate)(PTT)는 최근 섬유로 방사되어 카펫, 의류 등으로 응용된 이후 PTT를 주성분으로 하는 bicomponent 멜트블로운 부직포[4], 염색[5] 등의 연구가 활발히 이루어지고 있다. (중략)

• Proceedings of the Korean Fiber Society Conference
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• 1998.10a
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• pp.453-456
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• 1998

고분자들을 배합하여 기계적, 물리적, 화학적 성질이 우수한 새로운 고분자 재료를 제조할 때 이들 고분자의 상용성을 증가시켜 줄 수 있는 상용화제의 존재가 필수적인데, 주로 블록이나 그라프트 공중합체들이 많이 이용되고 있다. 이러한 공중합체들은 아주 최소량이 사용되고서도 소기의 목적을 달성할 수 있어야 하는데, 이를 위해서는 이러한 공중합체들은 분자구조상 몇 가지 조건을 만족해야 한다. 예를 들면 계면에 존재하면서 넓은 표면적을 감싸주어야 하고 블렌드되는 고분자들과 아주 잘 섞여야 한다는 것 등이 그것이다. (중략)

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.255-258
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• 2002

폴리에스테르계 고분자를 용융온도 이상에서 가공하면 두 고분자간의 화학적인 상호교환반응이 일어나고, 이러한 상호에스테르 교환반응은 이들의 공중합체를 생성시켜 블렌드계의 상용성을 증대시킬 수 있으며, 구조와 물리적 성질을 상당한 수준까지 변화시킬 수 있기 때문에 용융가공시 중요한 인자가 되고 있다. 일반적으로 상호에스테르 교환반응에 의해 공중합체가 형성될 때 반응초기에는 블록 공중합체가 형성되며, 반응이 진행될수록 랜덤 공중합체가 형성 [1] 되며, 블렌딩 시간, 온도 그리고 조성비에 따라 상호교환방응 정도가 달라지게 된다[2-3]. (중략)