• Title/Summary/Keyword: Methacrylic acid

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Evaluation of New Selective Molecularly Imprinted Polymers for the Extraction of Resveratrol from Polygonum Cuspidatum

  • Cao Hui;Xiao Jian Bo;Xu Ming
    • Macromolecular Research
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    • v.14 no.3
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    • pp.324-330
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    • 2006
  • Four different molecularly imprinted polymers (MIPs) were prepared using resveratrol as the template, methacrylic acid (MAA) or acrylamide (AA) as functional monomers, 2,2-azobisisobutyronitrile (AIBN) as the initiator, and thermo- or photo-induced polymerization. The ability of the different polymers to rebind selectively not only the template but also other phenols was evaluated. In parallel, the influence of the different templates and functional monomers used during polymer syntheses on the performance of the obtained MIPs was also studied through different rebinding experiments. The binding ability and selectivity of the polymer were studied by static balance method and Scatchard analysis. It was concluded that AA-based polymer by photo-induced polymerization presents the best properties to be used as a selective absorbent for the extraction of resveratrol.

The Preparation of D-Phenylalanine Imprinted Microbeads by a Novel Method of Modified Suspension Polymerization

  • Khan, Hamayun;Park, Joong-Kon
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.11 no.6
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    • pp.503-509
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    • 2006
  • Molecularly imprinted polymeric microbeads (MIPMs) were prepared by the suspension and modified suspension polymerization methods using D-phenylalanine as the template, methacrylic acid as the functional monomer, ethylene glycol dimethacrylate as the cross-linker, toluene as the porogen, polyvinyl alcohol as the stabilizer, and sodium dodecyl sulfate as the surfactant. The addition of a surfactant to the conventional suspension polymerization mixture decreased the mean particle size of the MIPMs and increased the adsorption selectivity. For the modified suspension polymerization method, the mean particle size of the MIPMs was smaller than the particle size of MIPMs prepared via conventional suspension polymerization. Moreover, the adsorption selectivity improved considerably compared to the adsorption selectivities of MIPs reported previously.

A Study on The Tracking Resistance and Mechanical strength of Epoxy Composites due to Boiling Absorption (비등에 따른 에폭시 복합체의 내트래킹성과 기계적강도에 관한 연구)

  • 김경민;김탁용;이덕진;강태오;홍진웅;김재환
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.07a
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    • pp.165-168
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    • 2000
  • This paper presents the tracking resistance and mechanical strength due to boiling absorption of epoxy resin. The single network structure specimen(E series) formed of epoxy alone and interpenetrating polymer network(IPN) structure specimen(EM series) which epoxy resin was taken as first network and methacrylic acid resin as second network were manufactured. As adding $SiO^2$ filler classified by o[phr], 50[phr] and 100[phr] to those specimens, six kinds of specimens were manufactured and boiled in water during 2, 4, 8, 16, 32 and 64[hours]. As a result, it was confirmed that the tracking breakdown time of E series showed a abrupt decrease with boiling time increasing, but that of EM series was decreasing smoothly. Also, it was verified that the degrading rates of mechanical strength was lowerd according to improvement of adhension strength in case of EM series.

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Thermally Crosslinkable Second-Order Nonlinear Optical Polymer Using Pentaerythritol tetrakis(2-mercaptoacetate) as Crosslinker

  • 한관수;심상연;이용석;장웅상;김낙중
    • Bulletin of the Korean Chemical Society
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    • v.19 no.11
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    • pp.1168-1171
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    • 1998
  • Two kinds of second-order nonlinear optical copolymers were prepared by the copolymerization of the vinyl monomers containing NLO chromophore, methacrylic acid, and methyl methacrylate or butyl methacrylate. Glass transition temperatures (Tg of copolymers were around 130 ℃. The copolymers were soluble in common organic solvents such as tetrahydrofuran (THF), cyclohexanone, and N,N-dimethylformamide (DMF). The crosslinked copolymer was obtained by thermal treatment using pentaerythritol tetrakis(2-mercaptoacetate) as a crosslinker and became insoluble in tetrahydrofuran (THF) and N,N-dimethylformamide (DMF). Poling was carried out at 120 ℃ for 20 min and identified with UV-Vis spectroscopy. Electro-optic coefficient (r33) measurement showed a value of 35 pm/V for polymer 2 at 633 nm. Temporal stability of copolymers was improved owing to the crosslinked network, which was successfully obtained at 170 ℃ for 30 min after poling.

Plasticization in Unclustered Poly(methyl methacrylate) Ionomers

  • 김준섭;김희석;Adi Eisenberg
    • Bulletin of the Korean Chemical Society
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    • v.19 no.6
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    • pp.625-628
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    • 1998
  • The dynamic mechanical properties of the unclustered cesium neutralized poly(methyl methacrylate-co-methacrylic acid) ionomers plasticized with three different plasticizers of low molecular weight were investigated. It was found that the effectiveness of the plasticization followed the order: glycerol (Gly) 4-decylaniline (4DA) >dioctyl phthalate (DOP). For the ionomer plasticized with Gly, the only effect was a significant decrease in the Tg. Thus it is concluded that the polar plasticizer not only increases the mobility of the ionomer but also dissolves the ionic groups. In the case of the 4DA-plasticized ionomer, both a drastic decrease in the Tg and the appearance of a second glass transition were observed. Therefore, it is suggested that the nonpolar 4DA molecules partition evenly in the poly(methyl methacrylate) matrix and cluster phases via hydrogen bonding between the aniline group of the plasticizer and the carbonyl groups of the ionomer. As a result, the Tg is lowered, multiplets can form, and the material behaves like a clustered ionomer.

Change of Physical Properties of Hydrogel Lens Polymer Containing Isocyanate Group with Ag Nanoparticle

  • Cho, Seon-Ahr;Sung, A-Young
    • Journal of Integrative Natural Science
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    • v.7 no.1
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    • pp.5-10
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    • 2014
  • A study that copolymerized Ag nanoparticle and furfuryl isocyanate with the crosslinking agent EGDMA (ethylene glycol dimethacrylate), HEMA (2-hydroxyethyl methacrylate), MMA (methyl methacrylate), MA (methacrylic acid) and the initiating agent AIBN (azobisisobutyronitrile) is presented. Measurement of the physical characteristics of the produced macromolecule showed that the water content is 32.08~32.67%, refractive index 1.446~1.448, visible light transparency 83.2~67.6%, contact angle $68.2{\sim}83.5^{\circ}$ and tensile strength 0.541~0.755 kgf. It is also demonstrated that the addition of Ag nanoparticles is associated with the reduction of UV-B transmittance and increase in tensile strength. The results show that the produced copolymer can be used as a material for ophthalmic lenses with durability and UV-blocking properties.

Synthesis of Acrylate Binders for Negative Photoresist (네가티브 포토레지스트용 아크릴레이트계 바인더 합성)

  • Kim, Nan-Soo;Nam, Byeong-Uk
    • Journal of the Semiconductor & Display Technology
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    • v.8 no.3
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    • pp.25-30
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    • 2009
  • In this study, we synthesized novel UV-curable binders and applied for negative photoresist of display device. First, we synthesized UV-curable binders by radical polymerization with a mixture of Styrene/Methyl methacrylate/Methacrylic acid/Glycidyl methacrylate/N-Cyclohexylmaleimide at a fixed composition. Following the first step, we prepared a negative photoresist mixture optimized with photo sensitive initiator and others for the litho test. And then, we studied resolution and film retention with molecular weight of each binders and numerical value of Alkaline Desolution Rate(ADR). As a result of the litho test, we found that if the novel polymers have same numerical value of ADR, the resolution decreased and the film retention increased with the increasing of molecular weight of photoresist binder.

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Effect of Particle Sizes of Polymer Binders for Pigment Inks on Touch of Fabrics (안료 잉크용 바인더의 입자 크기가 직물의 태에 미치는 영향)

  • Park, Seongmin;Han, Minwoo;Jeong, Euigyung
    • Textile Coloration and Finishing
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    • v.32 no.4
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    • pp.226-231
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    • 2020
  • This study investigated effect of particle sizes of polymer binders for digital textile printing(DTP) pigment inks on touch of fabrics. The polymer binders were synthesized via miniemulsion polymerization of methyl methacrylate(MMA), butyl acrylate(BA), N-ethylolacrylamide(NEA) and methacrylic acid(MAA). The prepared binders were applied to black pigment inks and those black pigment inks were used to dye cotton fabrics. Then, color strength, rubbing fastness, stiffness, surface and bending properties of the dyed fabrics were investigated. Depending on the particle size of the polymer binder used, color strength, friction fastness, stiffness, surface and bending properties change. Generally, the larger the particle size of the polymer binder, the softer properties.

Capacitive Humidity Sensor Using Reactive Methacrylate Copolymers (반응성이 있는 메타크릴레이트 공중합체를 이용한 정전용량형 습도센서)

  • 공명선;이임렬
    • 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.

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Characteristics with Casting Molding of Functional EPDM Through Grafting Polymerization

  • Yoon, Yoo Mi;Kim, Donghyun;Kim, Jeong Hoe;Kim, Minseub;Lee, Won Ki;Park, Chan Young
    • Elastomers and Composites
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    • v.52 no.3
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    • pp.194-200
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    • 2017
  • After the grafting of methacrylic acid (MA) to ethylene propylene diene monomer (EPDM), a new peak at $1704cm^{-1}$ corresponding to the carboxylic acid group was observed in the infrared (IR) spectrum. This characteristic MA molecule peak grew larger as the MA contents were increased. After casting films were prepared from pure EPDM and MA-grafted EPDM, differential scanning calorimeter (DSC) measurements were made the pure EPDM exhibited a melting point of approximately $45^{\circ}C$ while that of the MA-grafted EPDM was $135{\sim}140^{\circ}C$. As the graft ratio of MA increased, the absorbed heat capacity increased at temperatures near $135{\sim}140^{\circ}C$, indicating that an increased amount of MA reacted. Furthermore, owing to the addition of crystalline MA, it is expected that strength of the elastomer will improve as the graft ratio increases, as a result of the increased number of hard segments.