• Journal of Adhesion and Interface
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• v.8 no.1
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• pp.8-14
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• 2007

Poly(urethane-methyl methacrylate) hybrid emulsions can be controlled with their thermal, mechanical and anti-chemical properties as plastic coating materials. In this study, water dispersed poly(urethane-methyl methacrylate) hybrid emulsions were prepared by prepolymer synthesis and soap free emulsion polymerization. For imparting hydrophilicity on polyurethane prepolymer, 2,2-bis (hydroxymethyl) propionic acid was added to the polyurethane prepolymer with methyl methacrylate monomer and was neutralizated by triethylamine (TEA). After neutralization, the prepolymer mixture was dispersed in the water phase with stable droplets. The synthesis was carried out with chain extension from the ethylene diamine and initiation of methyl methacrylate by soap free emulsion polymerization. Stable poly(urethane-methyl methacrylate) hybrid emulsion was successfully obtained with different synthetic conditions and acrylic monomer contents. Poly(urethane-methyl methacrylate) hybrid emulsion were characterized and compared with tensile strength, viscosity, and adhesion properties.

• Macromolecular Research
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• v.9 no.2
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• pp.122-128
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• 2001

Monodisperse composite latex particles with size of ca. 300 nm, which consist ofn-butyl acrylate as a soft phase and methyl methacrylate as a hard phase with different morphology, were synthesized by seeded multi-stage emulsion polymerization. Three types of composite latex particles including random-, core/shell-, and gradient-type particles were obtained by using different monomer feeding methods during semi-batch emulsion polymerization. Effect of poly(butyl acrylate)-poly(methyl methacrylate) rubber particle morphology on the mechanical and rheological properties of rubber toughened poly(methyl methacrylate) was investigated. Among three different rubber particles, the gradient-type rubber particle showed better toughening effect than others. No significant variation of rheological property of poly(methyl methacrylate)/rubber blends was observed for the different rubber particle morphology.

• 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.

• Membrane Journal
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• v.25 no.6
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• pp.515-523
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• 2015

While commercial polystyrene-based ion exchange membranes have simple manufacturing processes, they also possess poor durability due to their brittleness. Poly(ethylene glycol)methyl ether methacrylate with hydrophilic side chains of poly(ethylene glycol) was used as a co-monomer to make the membranes have improved flexibility. Hydrophilicity/hydrophobicity of the anion exchange membranes were able to be adjusted by varying the chain lengths of the poly(ethylene glycol). For the preparation of the anion exchange membranes, a porous PE substrate was immersed into monomer solutions and thermally polymerized. The prepared membranes were subsequently reacted with trimethylamine to produce anion exchange functional groups, Quaternary ammonium salts. The prepared pore-filled anion exchange membranes were evaluated in terms of ion exchange capacity, electric resistance, elongation at break and water uptake.

• Bulletin of the Korean Chemical Society
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• v.22 no.8
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• pp.914-916
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• 2001

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.237.1-237.1
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• 2003

Cefuroxime axetil, a broad spectrum antibiotic, has been known to form a gelatinous mass in contact with aqueous media, which could lead to poor dissolution. Therefore, this study was conducted for removing the gelling phenomenon and thereby obtaining a favorable dissolution profile. We have found that the addition of poly (methacrylic acid, methyl methacrylate) could not only inhibit the tendency of cefuroxime axetil to form a gel but also showed the good dissolution profile compared to the formula without poly (methacrylic acid, methyl methacrylate). (omitted)

• Polymer(Korea)
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• v.33 no.3
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• pp.230-236
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• 2009

Water soluble vinyl acetate/alkyl methacrylate copolymers were prepared by the emulsion copolymerization of vinyl acetate and various methacrylates such as methyl methacrylate (MMA) and ethyl methacrylate (EMA). Potassium persulfate (KPS) and ammonium persulfate (APS) were used as an initiator. Poly (vinyl alcohol) (PVA) was used as a protective colloid. The drying characteristics of the prepared poly(vinyl acetate-co-methyl methacrylate) (PVAc/PMMA), poly(vinyl acetate-co-ethyl methacrylate) (PVAc/PEMA) were studied using moisture meter at the temperature between 100 and $200^{\circ}C$. The significant results are described as follows. The activation energy of the isothermal drying process of the copolymers has the order of PVAc/PMMA> PVAc/PEMA> PVAc.

• 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.8 no.6
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• pp.292-297
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• 2000

The theoretical synthesis of the isotactic and syndiotactic poly(methyl methacrylate) were carried out as a model for real polymerization reactions following the normal chain reaction processes by repeating the uniform localization of wave functions with inclusion of the interaction between the end group of the cluster and an attaching molecule by the elongation method, and then, the calculated value was compared with the usual PM$_3$ calculation. The results revealed that a reaction of cluster with monomer molecules has made it possible to calculate the electronic structure and total energy of polymer with nearly infinite length and a matrix of constant dimension. The isotactic poly(methyl methacrylate) is more stable than syndiotactic one. The same tendency have been found between the experimentally measured properties and a calculated total energy to explain the chain motion in isotatic and syndiotactic poly(methyl methacrylate).

• Macromolecular Research
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• v.17 no.10
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• pp.757-762
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• 2009

The micro domain structures and crystallization behavior of the binary blends of poly(methyl methacrylate)-b-poly(pentafluorostyrene)-b-poly(methyl methacrylate) (PMMA-PPFS-PMMA) triblock copolymer with a low molecular weight poly(vinylidene fluoride) (PVDF) were investigated by small-angle X-ray scattering (SAXS), small-angle light scattering (SALS), transmission electron microscopy (TEM), optical microscopy, and differential scanning calorimetry (DSC). A symmetric, PMMA-PPFS-PMMA triblock copolymer with a PPFS weight fraction of 33% was blended with PVDF in N,N-dimethylacetamide (DMAc). In the wide range of PVDF concentration between 10.0 and 30.0 wt%, PVDF was completely incorporated within the PMMA micro domains of PMMA-PPFS-PMMA without further phase separation on a micrometer scale. The addition of PVDF altered the phase morphology of PMMA-PPFS-PMMA from well-defined lamellar to disordered. The crystallization of PVDF significantly disturbed the domain structure of PMMA-PPFS-PMMA in the blends, resulting in a poorly-ordered morphology. PVDF displayed unique crystallization behavior as a result of the space constraints imposed by the domain structure of PMMA-PPFS-PMMA. The pre-existing microdomain structures restricted the lamellar orientation and favored a random arrangement of lamellar crystallites.