• Title/Summary/Keyword: in - situ polymerization

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In situ synthesis of acrylic emulsion for improvement of anti corrosion property on steel plate (금속 코팅용 아크릴 올리고머 에멀젼의 합성에 관한 연구)

  • Lee, Soo;Park, Keun-Ho;Jin, Seok-Hwan;Park, Shin-Kyu
    • Journal of the Korean Applied Science and Technology
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    • v.25 no.4
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    • pp.485-494
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    • 2008
  • The acrylic coating emulsions were prepared by the emulsion polymerization to protect the surface of steel plate from the corrosion chemicals like acid, base and salt water. MMA(methyl methacrylate), styrene, BA(butyl acrylate), and 2-HEMA(2-hydroxyethyl methacrylate) were used as monomer. KPS(potassium persulfate) and SBS(sodium bisulfite) as redox initiator and SDBS(sodium dodecylbenzene sulfonate) as emulsifier were used on the emulsion polymerization reaction. The most stable in-situ coating was obtained when 10% of MMA was added. Both particle size and quantity in emulsion were decreased as increasing the mount of SDBS. the most stable prepared coating emulsion with polyisocyanate crosslinker showed very high anticorrosion properties on the coated steel layer to salt water, whereas no significant improvement of anticorrosion property to acdic and basic condition it showed.

Preparation and Characterization of Monolithic Poly(methacrylic acid - ethylene glycol dimethacrylate) Columns for High Performance Liquid Chromatography

  • Yan, Hong-yuan;Row, Kyung-Ho
    • Bulletin of the Korean Chemical Society
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    • v.27 no.1
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    • pp.71-76
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    • 2006
  • Porous polymer monolithic columns were prepared by the direct free radical copolymerization of methacrylic acid and ethylene glycol dimethacrylate within the confines of a chromatographic column in the presence of toluene-dodecanol as a porogenic solvent. The separation characteristics of the monolithic columns were tested by a homologous series of xanthine derivatives, theophylline and caffeine. The effects of the polymerization mixture composition and polymerization condition, mobile phase composition, flow rate and temperature on the retention times and separation efficiencies were investigated. The results showed that the selection of correct porogenic solvents and appropriate polymerization conditions are crucial for the preparation of the monolithic stationary phases. The separation efficiency was only extremely weakly dependent on flow rate and temperatures. Hydrogen-bonding interaction played an important role in the retention and separation. Compared with conventional particle columns, the monolithic column exhibited good stability, ease of regeneration, high separation efficiency and fast analysis.

Synthesis of CO2 Adsorbent with Various Aminosilanes and its CO2 Adsorption Behavior (다양한 아미노실란을 이용한 이산화탄소 흡착제 합성 및 흡착 특성)

  • Jeon, Jae Wan;Ko, Young Soo
    • Applied Chemistry for Engineering
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    • v.27 no.1
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    • pp.80-85
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    • 2016
  • The carbon dioxide adsorption behavior of silica with a large specific surface area and pore volume functionalized with aminosilane compounds via in-situ polymerization and functionalization method were investigated. The organosilanes include amino functional group capable of adsorbing carbon dioxide. Elemental analyzer, in situ FT-IR and thermogravimetric analyzer were used to characterize the sorbents and to determine their $CO_2$ adsorption behavior. Comparison of different aminosilane loading in the support revealed that polyaminosilane functionalization of 70% of the pore volume in the support was better in terms of the adsorption capacity and amine efficiency than that of 100% of the pore volume of the support. Furthermore, the sorbents showed a higher adsorption capacity at an adsorption temperature of $75^{\circ}C$ than at $30^{\circ}C$ due to the thermal expansion of synthesized polyaminosilanes inside the pore of silica. The N-[3-(trimethoxysilyl)propyl]ethylenediamine (2NS) sorbent with 70% of the pore volume functionalized showed the highest adsorption capacity of 9.2 wt% at $75^{\circ}C$.

Synthesis and Characterization of Allyl Ester Resin-Layered Silicate Nanocomposite (알릴 에스터 수지-층상 실리케이트 나노복합재료의 합성과 특성)

  • 팽세웅;김장엽;허완수;조길원;이상원
    • Polymer(Korea)
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    • v.28 no.2
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    • pp.177-184
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    • 2004
  • Polymer-clay nanocomposite containing the low amounts of clay shows improved physical, mechanical properties. In this study, allyl ester prepolymer was synthesised by reactions of the diallyl terephthalate monomers and the 1,3-butanediol monomers. Nanocomposites of allyl ester prepolymer and the two kinds of the organically layered silicate were prepared by using the intercalation method as well as the in-situ polymerization method using. By varying the amount of clay content, curing conditions, and feeding conditions. the nanocomposite was studied using X-ray diffraction. From XRD results, allyl ester-Cloisite 30 B nanocomposite made by the in-situ polymerization method shows better exfoliation behavior compared with the intercalation method. It can be said that the transesterification reaction between functional groups (-OH) of intercalant and monomers results in the increased gallery distance. Also mechanical and thermal properties indicate that the dispersity of clay is an important factor for improving physical properties of the nanocomposite.

In-Situ Synthesis of PS/(-)Silica Composite Particles in Dispersion Polymerization Using An ($\pm$) Amphoteric Initiator

  • Hwang, Deok-Ryul;Hong, Jin-Ho;Lee, Jeong-Woo;Shim, Sang-Eun
    • Macromolecular Research
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    • v.16 no.4
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    • pp.329-336
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    • 2008
  • Core/shell ($\pm$)PS/(-)silica nanocomposite particles were synthesized by dispersion polymerization using an amphoteric initiator, 2,2'-azobis [N-(2-carboxyethyl)-2,2-methylpropionamidine] ($HOOC(CH_2)_2HN$(HN=) $C(CH_3)_2CN$=NC $(CH_3)_2C$(=NH)NH $(CH_2)_2COOH$), VA-057. Negatively charged (-6.9 mV) silica was used as the stabilizer. The effects of silica addition time and silica and initiator concentrations were investigated in terms of polymerization kinetics, ultimate particle morphology, and size/size distribution. Uniform hybrid microspheres with a well-defined, core-shell structure were obtained at the following conditions: silica content = 10-15 wt% to styrene, VA-057 content=above 2 wt% to styrene and silica addition time=0 min after initiation. The delay in silica addition time retarded the polymerization kinetics and broadened the particle size distribution. The rate of polymerization was strongly affected by the silica content: it increased up to 15 wt% silica but then decreased with further increase in silica content. However, the particle size was only marginally influenced by the silica content. The zeta potential of the composite particles slightly decreased with increasing silica content. With increasing VA-057 concentration, the PS microspheres were entirely coated with silica sol above 1.0 wt% initiator.

Preparation and Characterization of Polyimide/Carbon Nanotube Composites by in-situ Polymerization (In-situ 중합법에 의한 Polyimide/Carbon Nanotube 복합재료의 제조 및 특성)

  • Seo, Min-Kang;Park, Soo-Jin
    • Proceedings of the Korean Fiber Society Conference
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    • 2003.10b
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    • pp.223-224
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    • 2003
  • Polyimides (PI) are widely used in applications ranging from microelectronics to aerospace. Due to their insulating nature, significant accumulation of electrostatic charge may result on their surface, causing local heating and premature degradation to electronic components or space structures. Over the past decade, several publications have been made in fabrication and charaterization of CNT nanocomposites [1,2]. (omitted)

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