• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.317-317
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• 2006

Dendronized linear polymers have recently come forward as new materials for nanoscale applications. These "molecular cylinders" may be modified with specific chemical makeup, rigidity, surface decoration, and backbone properties much like their spherical analogs, dendrimers. There exist three main synthetic pathways to yield dendronized polymers: (i) graft-to; (ii) graft-from; and (iii) macromonomer. We present an efficient "graft-to" approach towards dendronized microstructures utilizing click chemistry. With the capacity to manipulate their chemical composition, these dendronized structures have already found broad use in site-isolation for catalysis, nanolithography and organic light emitting diodes. These and other potential applications of these materials will be also presented.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.2
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• pp.142-147
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• 2005

In this work, a gel polymer electrolyte (GPE) was prepared using polyoxyalkylene glycol acrylate (POAGA) as a macromonomer LiCoO$_2$/GPE/graphite cells were prepared and their electrochemical properties were evaluated at various current densities and temperatures. The ionic conductivity of the GPE was more than 6.2${\times}$10$^{-3}$ S$.$$cm^{-1}$ / at room temperature. The GPE had good electrochemical stability up to 4.5 V vs. Li/Li$^{+}$. POAGA-based cells were showed good electrochemical performances such as rate capability, low-temperature performance, and cycleability. The cells, also, passed a safety test such as the overcharge and nail-penetration test.t.

• Elastomers and Composites
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• v.51 no.2
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• pp.154-160
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• 2016

The four different vinyl monomers in the reaction of isocyanate-terminated polyurethane prepolymer were used for the preparation of macromonomers and successfully employed in the dispersion polymerization of styrene. The chemical structures of vinyl monomer in macromonomers influenced on the polystyrene particle characteristics, such as the conversion, weight average molecular weights ($M_w$), polydispersity index (PDI), weight average diameter ($D_w$), and uniformity. The conversion of polystyrene increased with amounts of methyl group in vinyl monomer. Also the uniformity of polystyrene particles increased with amounts of methyl group in vinyl monomer.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.360-361
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• 2008

A new kind of SBM co-polymer binder as styrene, n-butyl acrylate, and methacrylic acid (SBM) monodisperse co-polymer binder materials basted on $TiO_2$ pastes was synthesized and this $TiO_2$ pastes were applied of dye-sensitized solar cells (DSSCs). The SBM co-polymer binder was prepared by soap-free emulsion copolymerization using a PEG-EEM macromonomer. The photoanodes were characterized by morphology investigated from field emission scanning electron microscopy (FE-SEM). The photoelectrochemical properties of the thin films and the performance of DSSCs were measured by photovoltaic-current density. DSSC based on the emulsion co-polymer binder was obtained conversion efficiency of 7.1% under irradiation of AM 1.5($100mWcm^{-2}$).

• Macromolecular Research
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• v.11 no.5
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• pp.311-316
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• 2003

The kinetics of photoinitiated polymerization of dimethacrylate macromonomers have been studied to determine the diffusion-controlled reaction parameters using attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR). A predicted kinetic rate expression with a diffusion control factor was employed to estimate an effective rate constant and to define the reaction-controlled and diffusion-controlled regimes in the photopolymerization. An effective rate constant, k$_{e}$, can be obtained from the predicted kinetic rate expression. At the earlier stages of polymerization, the average values of kinetic rate constants do not vary during the reaction time. As the reaction conversion, $\alpha$, reaches the critical conversion, $\alpha$$_{c}$, in the predicted kinetic expression, the reaction becomes to be controlled by diffusion due to the restricted mobility of dimethacrylate macromonomers. A drop in value of effective rate constant causes a drastic decrease of reaction rate at the later stages of polymerization. By determining the effective rate constants, the reaction-controlled and diffusion-controlled regimes were properly defined even in the photopolymerization reaction system.m.m.

• Macromolecular Research
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• v.17 no.1
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• pp.51-57
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• 2009

Using glycidyl methacrylate-linked poly(dimethylsiloxane), methyl methacrylate was polymerized in supercritical $CO_2$. The effects of $CO_2$ pressure, reaction time, and mixing on the yield, molecular weight, and molecular weight distribution (MWD) of the poly(methyl methacrylate) (PMMA) products were investigated. The shape, number average particle diameter, and particle size distribution (PSD) of the PMMA were characterized. Between 69 and 483 bar, the yield and molar mass of the PMMA products showed a trend of increasing with increasing $CO_2$ pressure. However, the yield leveled off at around 345 bar and the particle diameter of the PMMA increased until the pressure reached 345 bar and decreased thereafter. With increasing pressure, MWD became more uniform while PSD was unaffected. As the reaction time was extended at 207 bar, the particle diameter of PMMA decreased at $0.48{\pm}0.03%$ AIBN, but increased at 0.25% AIBN. Mixing the reactant mixture increased the PMMA yield by 18.6% and 9.3% at 138 and 207 bar, respectively.

• Macromolecular Research
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• v.16 no.2
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• pp.120-127
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• 2008

Glycidyl methacrylate linked poly(dimethylsiloxane) (GMA-PDMS) was synthesized and used as a stabilizer for the dispersion polymerization of methyl methacrylate (MMA) in supercritical $CO_2$. This study examined the effect of the concentrations of the stabilizer, 2,2'-azobisisobutyronitrile (AIBN) initiator, and MMA on the yield, molecular weight, and morphology of the poly(methyl methacrylate) (PMMA) product. PMMA was obtained in 94,6% yield using only 0,87 wt% GMA-PDMS, When the AIBN concentration was increased from 025 to 1.06 wt%, the molecular weight and particle size of the PMMA decreased from 56,600 to 21,600 and from 4.1 to $2.7{\mu}m$, whereas the particle size distribution increased from 1.3 to 1.9. The $M_n$ of the PMMA product ranged from 41,600 and 55,800 under typical polymerization conditions. The PMMA particle diameter ranged from 1.8 to $11.0{\mu}m$ and the particle size distribution ranged from 1.4 to 1.8.

• Elastomers and Composites
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• v.45 no.4
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• pp.256-262
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• 2010

Dispersion polymerization of methyl acrylate, ethyl acrylate, butyl acrylate, and glycidyl methacrylate were performed in supercritical $CO_2$ at $80\;^{\circ}C$ and 346 bar. Glycidyl methacrylate linked poly(dimethylsiloxane) (GMS-PDMS) surfactant, which was prepared by linking glycidyl methacrylate to monoglycidyl ether terminated PDMS with amino-propyltriethoxysilane, was used as surfactant for the dispersion polymerization in $CO_2$. The yield of the poly(alkyl acrylate) polymers, synthesized in $CO_2$ medium, decreased as the alkyl tail of the acrylate monomers increased. Poly(glycidyl methacrylate) and poly(methyl acrylate) were produced in bead form whereas poly(ethyl acrylate) and poly(butyl acrylate) were viscous liquid. The poly(glycidyl methacrylate) particles had a number average diameter of 2.45 ${\mu}m$ and monodisperse distribution. The poly(methyl acrylate) had a number average diameter of 0.52 ${\mu}m$ and the particle size distribution was bimodal. The glass transition temperatures ($T_g$) of the poly(glycidyl methacrylate) and the poly(alkyl acrylate) products were 4~9 K higher than the $T_g$ of the corresponding acrylate polymers synthesized in conventional processes.