• 전기화학회지
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• 제16권4호
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• pp.198-203
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• 2013

본 실험에서는 MMA와 tBMA의 공중합체를 합성하고, tert-butyl 그룹의 가수분해를 선택적으로 유도하여 poly(MMA-co-MA)를 제조하였다. 또한 말단에 에폭시기를 함유한 다양한 분자량의 PEO와 MA와의 grafting-onto 커플링 반응을 통해 같은 주사슬을 가지지만 부사슬의 길이가 다른 poly(MMA-co-PEGMA)를 합성하여 조성이 이온전도도에 미치는 영향을 평가하였다. AC-impedance로 측정한 상온 이온전도도는 MMA의 몰분율이 82%에서 $5.11{\times}10^{-8}Scm^{-1}$의 값이 얻어진 반면, 48%에서는 $1.88{\times}10^{-6}Scm^{-1}$로서 많은 PEGMA에서 높게 관찰되었다. 또한 에폭시기를 함유한 PEO의 분자량에 따라 이온전도도의 차이가 발생하는데, grafting-onto 법의 입체적 장애가 원인으로 고려되었다. 한편, 합성된 poly(MMA-co-PEGMA) 고분자 전해질은 상온에서 6V까지 우수한 전기화학적 안정성을 보여주었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
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• pp.1408-1409
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• 2006

In this paper, poly methyl methacrylate thin films were deposited on a ITO glass substrate using a plasma polymerization technique. In order to investigate the influence of the plasma coupling method and plasma conditions on the plasma polymerized poly methyl methacrylate (ppMMA) thin film properties, inductively coupled (ICP) and capacitively coupled plasma (CCP) were used to generate the plasma and the plasma parameters were varied. Molecular structures of the ppMMAs were investigated using a Fourier Transform Infrared (FT-IR) spectroscopy. Dielectric constants of the ppMMA thin films were investigated using a impedance analyzer (HP4192A, LF Impedance Analyzer). Current-Voltage (I-V) characteristics of the ppMMA thin films were investigated using a source measurement unit (SMU: Keithley 2400). Relationship between the plasma coupling technique/process parameter and ppMMA thin films properties were investigated.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.100-105
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• 1992

A mathematical model is developed for a CSTR in which free radical solution polymerization of methyl methacrylate(MMA) takes place. It turns out that five ordinary differential equations are to be treated simultaneously in order to predict the reactor performance. Although the reaction proceeds under the conditions of relatively low temperature and pressure, the system shows very complex bifurcation features due to the diffusion limitation (gel effect) and the temperature dependence of the kinetic parameters and physical properties. The effects of various system parameters on the reactor performance as well as on the polymer properties are investigated by using the bifurcation analysis. The application of the singularity theory enables us to divide the parameter space into several different regions, in each of which the system takes a unique steady state structure. Under certain circumstances, complex dynamic features such as HB points and limit cycles are observed and these should be taken into consideration in the reactor design.

• 공업화학
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• 제19권3호
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• pp.345-350
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• 2008

고분자함침콘크리트(PIC)는 물리화학적 물성뿐만 아니라 기계적 강도가 우수한 재료로서 성형된 일반 콘크리트를 변조하여 제조한다. PIC 제조공정은 성형된 공시체의 건조, 단량체의 함침, 중합공정으로 구성된다. PIC 제조공정 중 고분자 중합공정은 지금까지 주로 열 및 수중중합방법을 사용하여 콘크리트 내부의 온도구배가 크고 라디칼 생성이 억제되어 불균일한 중합을 초래하였다. 본 연구에서는 마이크로파를 이용한 중합 반응기를 제작하여 스티렌/메틸메타아크릴레이트(MMA) 1 : 1의 혼합물을 단량체로 사용한 PIC 제조의 중합공정에 사용하였다. 그 결과 열중합보다 매우 균일한 PIC를 제조할 수 있었으며, 30% 이상 중합도가 증가하였고, 공시체보다 기계적 압축강도는 600% ($800{\sim}1200kg_f/cm^2$)까지 증가하였으며, 내산성은 20% 이상 증가하였다. 또한 개시제는 1% 이하로 사용할 수 있었고 중합의 최적 조건은 400 W, 2450 MHz의 radiation 조사로 최적 온도는 $120^{\circ}C$였다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제55권1호
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• pp.30-33
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• 2006

Transparent indium tin oxide (ITO) anode surface was modified using $O_3$ Plasma and organic ultrathin buffer layers were deposited on the ITO surface using 13.56 MHz RF plasma polymerization technique. The EL efficiency, operating voltage and lifetime of the organic light-emitting device (OLED) were investigated in order to study the effect of the plasma surface treatment and role of plasma polymerized organic ultrathin buffer layer. Poly methylmethacrylate (PMMA) layers were plasma polymerized on the ITO anode as buffer layer between anode and hole transport layer (HTL). The plasma polymerization of the organic ultrathin layer were carried out at a homemade capacitive-coupled RF plasma equipment. N,N'-diphenyl-N,N'(3- methylphenyl)-1,1'-diphenyl-4,4'-diamine (TPD) as HTL, Tris(8-hydroxyquinolinato) Aluminum $(Alq_3)$ as both emitting layer (EML)/electron transport layer (ETL), and aluminum layer as cathode were deposited using thermal evaporation technique. Effects of the plasma surface treatment of ITO and plasma polymerized buffer layers on the OLED performance were discussed.

• 한국안전학회지
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• 제19권1호
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• pp.81-87
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• 2004

Composite particles using inorganic and organic chemicals were synthesized and the results of those reaction were compared to variation of temperature and agitation speed in presence of $CaCO_3$ which was adsorbed SDBS. Also the synthesises were optimized according to conversion rate of composite particles. In inorganic/organic core-shell composite particle polymerization, $CaCO_3$ adsorbed by 0.5wt% surfactant SDBS was prepared initially and then core $CaCO_3$ was encapsulated by sequential emulsion polymerization using MMA at the addition of APS 3.16${\times}$$10^{-3}$mol/L to minimize the coagulated PMMA particle itself during MMA shell polymerization. Encapsulated PMMA on $CaCO_3$ as inorganic/organic core-shell particles was verified by FT-IR and DSC analysis. It was found that the $CaCO_3$ was very well encapsulated by PMMA as shell. The surfaces were distinctly found as spindle shape and broad particle distribution after capsulation.

• Macromolecular Research
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• 제14권5호
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• pp.539-544
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• 2006

2-Furancarboxaldehyde-2-pyridinylhydrazone (FPH) and 5-methyl-2-furancarboxaldehyde-2-pyridinylhydrazone (MFPH) were synthesized and used as tridentate ligands of copper (I) bromide for the atom transfer radical polymerization of methyl methacrylate (MMA) and styrene. The polymerization of methyl methacrylate achieved high conversion and yielded polymers with a good control of molecular weight and low polydispersity (PDI=1.33). Higher PDI were observed in the polymerization of styrene. Using 1-phenyl ethylbromide (PEBr) and ethyl 2-bromoisobutyrate (EBiB) as model compounds for the polymeric chain ends, the activation rate constants of the new catalytic systems were measured. These results were correlated with the polymerization results and compared with another catalytic system previously reported.

• Macromolecular Research
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• 제15권3호
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• pp.244-255
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• 2007

Nucleation is the most sensitive stage in the preparation of highly cross-linked, monodisperse microspheres by dispersion polymerization, since the addition of a small amount of cross-linker results in particle deformation and coagulation. To overcome these problems, $5\;{\mu}m$ poly(methyl methacrylate) seed particles prepared by dispersion polymerization were used in the preparation of mono disperse, cross-linked PMMA particles containing up to 7 wt% divinylbenzene by seeded batch dispersion polymerization. Spherical particles with a narrow size distribution containing up to 8 wt% of EGDMA were prepared by seeded multi-batch dispersion polymerization processes. These particles were identified by scanning electron microscopy and DSC.

• 접착 및 계면
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• 제12권1호
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• pp.16-25
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• 2011

Core 입자로 methyl methacrylate (MMA), n-butyl methacrylate (BMA)를 하고 shell 입자로 MMA, BMA, stylene (St), 2-hydroxylethylmethacrylate (2-HEMA), acrylic acid (AA)를 각각 사용하여 개시제 aommonium persulfate (APS), 유화제로 sodium dodecyl benzene sulfonate (SDBS)의 농도(0.01~0.03 wt%), 단량체의 종류와 조성을 변화시켜 수용성 유화중합으로 다중 core-shell 복합입자를 제조하여 전화율, 입자경 및 입도 분포, 평균 분자량, 분자구조, 유리전이온도, 입자의 형태 및 인장강도와 신율을 각각 측정하여 다음과 같은 결론을 얻었다. SDBS 농도 0.02 wt%에서 MMA core-(BMA/St/AA) shell 복합인자가 전화율이 98%로 우수하였고, 입자 직경은 SDBS 농도 0.03 wt%에서 BMA core-(MMA/St/AA) shell의 복합입자가 $0.47{\mu}m$로 높게 나왔다. 유리전이온도 측정은 단일 core-shell 복합입자의 2군데에 비하여 다중 core-shell 복합입자는 3군데가 존재하여 shell단량체 내의 단량체의 종류와 조성에 따라 유리전이온도 조절도 가능하고 동시에 접착력이 향상된 접착소재로서 부직포 섬유 결속제로 사용될 수 있었다.

• 공업화학
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• 제17권4호
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• pp.426-431
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• 2006

Poly(methyl methacrylate) (PMMA)의 착색을 위하여 아크릴 그리고 비닐설폰기를 가지는 청색 및 오렌지 아조 염료들을 6-bromo-2-cyano-4-nitroaniline과 2,5-dimethoxy-4-(vinylsulfonyl)benzenamine을 3-acrylamido-(N,N-diethylamino) benzene과 3-methyl-(N,N-diethylamino)benzene의 아조 짝지음 반응을 이용하여 각각 합성하였다. 또한 알릴기를 가지는 염료는 비닐설폰과 allylamine과의 반응에 의하여 제조하였다. PMMA의 착색은 아크릴, 비닐설폰 그리고 알릴 작용기를 가지는 염료를 직접 methyl methacrylate (MMA)와 공중합하거나, MMA와 공중합한 고분자염료 및 반응성기가 없는 염료 2를 직접 MMA에 용해하여 중합과 동시에 착색하였다. 3가지로 착색한 PMMA의 염색 견뢰도를 여러 환경 조건에서 염료의 용해도를 비교하여 평가하였다.