• Elastomers and Composites
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• v.47 no.2
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• pp.168-173
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• 2012

Polystyrene-polyimide core-shell microsphere was prepared by dispersion polymerization using poly(amic acid) as the stabilizer. Iron oxide was formed at the microsphere by thermal decomposition of iron pentacarbonyl impregnated in the microsphere. The magnetic polystyrene-polyimide microsphere was monodisperse and the size was about 500 nm. The magnetic polystyrene-polyimide microsphere had 40% of iron oxide, which was identified as $Fe_3O_4$ by X-ray diffraction.

• Applied Chemistry for Engineering
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• v.24 no.5
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• pp.471-475
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• 2013

This study is about photosensitive microspheres prepared by coating alginate microspheres with gelatin-cinnamic acid conjugate. Firstly, alginate microspheres was prepared in water-in-oil (W/O) emulsion and then they were coated with gelatin- cinnamic acid conjugate. Herein, gelatin-cinnamic acid conjugate is obtained by the amidation between an amine group of gelatin and a carboxy group of cinnamic acid. Cinnamic acid is widely used as a photo-responsive material easy to dimerize and dedimeriz under UV irradiation at ${\lambda}$ = 254 nm and ${\lambda}$ = 365 nm, respectively. As shown in SEM-EDS, alginate was successfully coated with gelatin-ciannmic acid. By determining the absorbance of coated microspheres at 270nm, the amount of cinnamic acid per microspheres was 0.13/1. The SEM photos showed the size of coated microspheres is around $10{\mu}m$. And the degrees of dimerization and dedimerization were calculated to be 49% and 23% respectively. Then the release of FITC-dextran from the coated micrspheres was studied and release the degree was 42%. As a result, the coated microspheres have potential to be used as a photo-responsive drug carrier to delivery drugs.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.4
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• pp.449-455
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• 2022

Concrete is the most widely used construction material. The heavy self-weight of concrete may offer an advantage when developing high compressive strength and good dimensional stability. However, it is limited in the construction of super-long bridges or very high skyscrapers owing to the substantially increased self-weight of the structure. For developing lightweight concrete, various lightweight aggregates have typically been utilized. However, due to the porous characteristics of lightweight aggregates, the strength at the composite level is generally decreased. To overcome this intrinsic limitation, this study aims to develop a construction material that satisfies both lightweight and high strength requirements. The developed cementitious composite was manufactured based on a high volume usage of hollow glass microspheres in a matrix with a low water-to-cement ratio. Regardless of the tested hollow glass microspheres from among four different types, compressive strength outcomes of more than 60 MPa and 80 MPa with a density of 1.7 g/cm³ were experimentally confirmed under ambient and high-temperature curing, respectively.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.25-28
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• 2003

최근 생활수준의 향상과 함께 고기능성, 고감성의 제품이 요구되고 또한 소비패턴의 고급화, 다양화, 개성화와 함께 단시간의 유행변화에 신속하게 대응하기 위하여 섬유날염면에서도 다양한 색상과 디자인이 요구되고 있다. 그러나 기존의 rotary printing system에 의한 날염기술은 이러한 요구에 다양하고 신속한 대응을 할 수 없으므로 새로운 날염기술의 개발이 요구되었고 이에 xerography printing에 의한 직물날염이 주목받게 되었다. (중략)

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2003.04a
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• pp.89-92
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• 2003

SiO$_2$ 입자는 접착제, 충전제, 점성과 표면특성조절제 등 여러 산업에 응용되고 있다. 본 연구에서는 기능성을 가지는 입자를 제조하기 위해 SiO$_2$로써 기본적인 입자를 제조하고, 그 속에 소취특성을 가지는 TiO$_2$와 날염을 위한 EVA-microsphere를 포함시켜서 소취제로서, 그리고 날염 분체로서의 기능을 가진 입자들을 제조하고자 하였다. (중략)

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2003.04a
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• pp.97-100
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• 2003

최근 생활수준이 향상됨에 따라 고기능성, 고감성의 제품이 요구되고 있고 또한 소비패턴이 고급화, 다양화, 개성화 됨에 따라 단시간의 유행변화에 신속하게 대응하기 위하여 섬유날염면에서도 다양한 색상과 디자인 및 quick-response가 요구되고 있다. 그러나 기존의 rotary printing system에 의한 날염기술은 이러한 사회적 요구에 다양하고 신속한 대응을 할 수 없으므로 새로운 날염기술의 개발이 요구되었고 이에 xerography printing에 의한 직물날염이 주목받게 되었다. (중략)

• Proceedings of the Korean Fiber Society Conference
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• 1999.10a
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• pp.239-242
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• 1999

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.21-24
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• 2003

SiO$_2$ 입자는 촉매, 촉매의 담체, 크로마토그래피를 위한 충진제등 여러 산업에 응용되고 있다.$^{1)}$ 본 연구 에서는 기능성을 가지는 입자를 제조하기 위해 SiO$_2$로써 기본적인 입자를 제조하고, 그 속에 소취특성을 가지는 TiO$_2$와 날염을 위한 EVA-microsphere를 포함시켜서 소취제로서, 그리고 날염 분체로서의 기능을 가진 입자들을 제조하고자 하였다. 실리카(silica)는 일반적으로 규소산화물을 지칭하는 명칭으로서, SiO$_2$뿐 아니라 결정구조상 4-6개의 산소원자로 둘러싸인 모든 형태의 규소산화물을 지칭 하는 것이고$^{2)}$ 수용액상의 물유리는 실리카 졸의 값싼 상품으로 산업분야에 널리 알려져 있다. (중략)

• Textile Coloration and Finishing
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• v.15 no.4
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• pp.57-64
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• 2003

Poly(ethylene-co-vinyl acetate)(EVA) microspheres were prepared by a thermally induced phase separation. The microsphere formation occurred by the nucleation and growth mechanism in the metastable region. The diluent used was toluene. The microsphere formation and growth was followed by the cloud point of the optical microscope measurement. The microsphere size distribution, which was obtained by SEM observation and particle size analyzer, became broader when the polymer concentration was higher, the content of vinyl acetate in EVA copolymer was higher, and the cooling rate of EVA copolymer solution was lower.

• Textile Coloration and Finishing
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• v.17 no.4 s.83
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• pp.15-20
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• 2005

Poly(ethylene-co-vinylacetate)(EVA) microspheres were prepared by thermally induced phase separation in toluene. The microsphere formation occurred by the nucleation and growth mechanism in metastable region. The effects of the polymer or pigment weight percentage and cooling rate on microsphere formation were investigated. The microsphere formation and growth were followed by the cloud point of the optical microscope measurement. The microsphere size distribution, which was obtained by particle size analyzer, became broader when the polymer concentration was higher, the pigment concentration and the cooling rate of EVA copolymer solution were lower.