• 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.

• Polymer(Korea)
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• v.25 no.6
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• pp.848-854
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• 2001

The crystallization behavior of poly (ethylene terephthalate) (PET) /ethylene-methyl acrylate-glycidyl methacrylate copolymer (E-MeA-GMA) blend was studied. The extent of reaction and the reaction rate between PET and E-MeA-GMA were measured with torque rheometer, FT-IR and SEM. The effects of the grafting reaction on the crystallization behavior were investigated with DSC and time-resolved light scattering (TR-LS) techniques. The morphological change at the lamellar level was also examined by using a small angle X-ray scattering (SAXS) method.

• Macromolecular Research
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• v.12 no.6
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• pp.586-592
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• 2004

Poly(glycidyl methacrylate)-grafted polyethylene microbeads (POPM) presenting epoxy groups were prepared by radiation-induced graft polymerization of glycidyl methacrylate on the polyethylene microbead. The obtained POPM was characterized by IR spectroscopic, X-ray photoelectrons spectroscopy (XPS), scanning electron microscope (SEM), and thermal analyses. Furthermore, the abundance of epoxy groups on the POPM was determined by titration and elemental analysis after amination. The epoxy group content was calculated to be in the range 0.29-0.34 mmol/g when using the titration method, but in the range 0.53-0.59 mmol./g when using elemental analysis (EA) after amination. The lipase was immobilized to the epoxy groups of the POPM under various experi­mental conditions, including changes to the pH and the epoxy group content. The activity of the lipase-immobilized POPM was in the range from 160 to 500 unit/mg-min. The activity of the lipase-immobilized POPM increased upon increasing the epoxy group content. The lipase-immobilized POPM was characterized additionally by SEM, elec­tron spectroscopy for chemical analysis (ESCA), and EA.

• Bulletin of the Korean Chemical Society
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• v.14 no.5
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• pp.614-618
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• 1993

The photoacid generation efficiency of four N-hydroxyphthalimide sulfonate derivatives was studied by photo-crosslinking reaction of poly(glycidyl methacrylate) in solid film state. The relative photoacid generation efficiency was increased in the order of N-hydroxyphthalimide methanesulfonate > -toluenesulfonate > -nitrobenzenesulfonate > -dinitrobenzensulfonate, and the reaction was efficiently sensitized by benzophenone suggesting that this photoreactions is likely to proceed through its triplet excited state.

• Korean Chemical Engineering Research
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• v.43 no.5
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• pp.603-608
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• 2005

The molded macroporous poly (glycidyl methacrylate-co-ethylene glycol dimethacrylate) rods produced by a facile molding process were polymerized in situ within a tubular mold, chromatographic column ($4.6{\times}100mm$) by free radical polymerization. It was complemented by epoxy derivatized monolithic column and chemical modification of the epoxide groups with the sulphuric acid. By variation of the polymerization conditions, such as the ratio of the monomers, the porogen (pore generating material), and the temperature, the pore size could be varied, so the retention time of the samples may be adjusted. For the mixture of caffeine and tryptophan in the prepared monolithic column, the influences of polymerization material compositions to the efficiency, selectivity, and resolution of the monolithic column were investigated.

• Proceedings of the Korean Fiber Society Conference
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• 1997.04a
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• pp.246-250
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• 1997

• Archives of Pharmacal Research
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• v.28 no.8
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• pp.983-987
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• 2005

Hydrogels composed of glycidyl methacrylate dextran (GMD) and poly(acrylic acid, PM) were prepared by UV irradiation method for colon-specific drug delivery. GMD was synthesized by coupling of glycidyl methacrylate to dextran in the presence of 4-(N,N-dimethylamino)pyridine. GMD was photo-polymerized by ammonium peroxydisulfate as initiating system in phosphate­buffered solution (0.1 M, pH 7.4). And then, acrylic acid monomer was added and subsequently heat-polymerized by 2,2'-azobisisobutyronitrile as an initiator. The hydrogels exhibited high swelling ratio (about 20) at $37^{\circ}C$, and showed a pH-dependent swelling behavior. In addition, the swelling ratio of the hydrogel was remarkably enhanced to about 45 times in the presence of dextranase at pH 7.4. The swelling-deswelling behavior proceeded reversibly for the GMD/PM hydrogels between pH 2 and pH 7.4. Release of 5-aminosalicylic acid from the GMD/PAA hydrogels was evaluated in simulated gastrointestinal pH fluids in the absence or presence of dextranase. We concluded that the hydrogels prepared could be used as a dual-sensitive drug carrier for sequential release in gastrointestinal tract.

• Proceedings of the Korean Society of Rheology Conference
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• 2002.05a
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• pp.159-162
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• 2002

• 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.

• Korean Chemical Engineering Research
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• v.46 no.1
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• pp.124-130
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• 2008

In order to fabricate a modified poly (lactic acid) (PLA) for applications requiring high melt strength, a PLA has been irradiated in the presence of functional monomer of glycidyl methacrylate (GMA). Samples were prepared with various contents of GMA and irradiation dosages, and were characterized by observing their thermal and melt viscoelastic properties and gel faction. The complex viscosity and storage modulus of the modified PLA without GMA were lower than those of the original PLA. Those of the modified PLA decreased with increasing dosage. In the case of the modified PLA containing 0.1 phr or 0.3 phr of GMA, their changing tendency with dosage was similar to the irradiated PLA without GMA. However, the 5 kGy irradiated PLA containing 0.5 phr of GMA showed the greatly enhanced complex viscosity and storage modulus, which were about 3 and 10 times higher than those of the original PLA at a frequency of 0.1 rad/s, respectively.