• Bulletin of the Korean Chemical Society
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• 제32권12호
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• pp.4221-4226
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• 2011

Honeycomb-patterned polyvinypyrrolidone (PVP) thin films coated with nanometer-sized silver particles were prepared using honeycomb-patterned polystyrene (PS) template films fabricated by casting a polystyrene solution under humid condition. Silver was first metallized on the patterned PS films via silver nitrate ($AgNO_3$) reduction using tetrathiafulvalene (TTF) and a small amount of PVP as the reductant and dispersing agent, respectively. The effects of $AgNO_3$, TTF, and PVP solution concentrations during the reduction process in acetonitrile were determined to obtain a uniform silver-coated honeycomb-patterned PS film. Second, the silver-metallized patterned porous PS films were filled with high PVP concentration solutions via the spincoating process. Silver-coated patterned PVP films were obtained by peeling off the PVP layer from the template PS film after drying. The results show that the honeycomb-patterned PVP films uniformly coated with silver particles are conveniently obtained using the silver-coated patterned PS template, although the direct fabrication of these films using water droplets under humid conditions was not feasible because of the water solubility of PVP.

• 공업화학
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• 제16권4호
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• pp.513-518
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• 2005

혼합비율 및 반응온도의 변화에 따른 ZnO가 첨가된 PVC와 PS의 혼합 열분해 특성에 관한 연구를 TG와 GC-MS를 이용하여 수행하였다. 본 연구로부터 혼합물에 있어서 PS의 양이 증가할수록 액상 생성물은 증가하였으며 기상 생성물은 감소함을 알 수 있었다. 또한 ZnO의 첨가량이 증가할수록 기상 생성물과 염화수소의 발생량은 감소하였으며 염화수소의 발생 억제 및 액상 생성물의 최대수율을 얻기 위한 최적의 반응온도는 $500^{\circ}C$임을 알 수 있었다.

• Macromolecular Research
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• 제15권2호
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• pp.173-177
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• 2007

Living anionic and cationic polymerizations have been combined to prepare various types of comb-like copolymers composed of polystyrene (PS) and polyisoprene (PI) blocks, with a precisely controlled architecture. According to the relative placement of these elementary building blocks, combs with randomly distributed PS and PI or with poly(styrene-b-isoprene) diblock branches (I & II, respectively) can be prepared. The reaction procedure initially includes the synthesis of a poly(chloroethylvinyl ether) using living cationic polymerization, which is used as the reactive backbone to successively graft $PS^-Li^+$ and $PI^-Li^+$ or $PI-b-PS^-Li^+$ to obtain structures (I) or (II). The synthesis of Janus-type PS-comb-b-PI-combs (III) initially involves the synthesis of a diblock backbone using living cationic polymerization, which bears two distinct reactive functions having either a protected or activated form. Living $PS^-Li^+$ and $PI^-Li^+$ are then grafted, in two separate steps, onto each of the reactive functions of the backbone, respectively.

• 마이크로전자및패키징학회지
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• 제12권2호
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• pp.181-186
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• 2005

Polystyrene(PS)과 poly(methyl methacrylate)(PMMA)에 대하여 동일한 계면 특성을 갖는 3-(p-methoxyphenyl)propyltrichlorosilane(MPTS)의 자기조립 단분자막(self-assembled monolayer, SAM) 을 실리콘 웨이퍼 표면에 형성시켜 표면 특성을 개질하였다. 개질된 실리콘 웨이퍼에 PMMA 또는 PS가 원통형 나노구조를 형성하는 PS-b-PMMA 블록공중합체 박막을 코팅하여 원통형 나노구조가 실리콘 웨이퍼 표면에 대하여 수직 배향된 박막을 제조하였다. 수직 원통형 나노구조를 갖는 박막에 자외선 조사와 세척을 통하여 PMMA 블록을 선택적으로 제거하여 수직 나노기공 필름과 수직 나노막대 배열을 제조하였다. 제조된 나노기공 필름은 나노리소그래피 마스크로 사용이 가능하다.

• Elastomers and Composites
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• 제45권1호
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• pp.17-24
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• 2010

본 논문에서는 MWCNT/PS 복합재료 제조 시, MWCNT의 표면 개질에 의한 분산도에 따른 열 및 전기전도도에 관하여 연구하였다. 다양한 종류의 MWCNT를 PS/THF 용액에서 분산시킨 후 침전을 통하여 복합재료를 제조하였다. 사용된 MWCNT는 pristine MWCNT의 상이동 촉매 존재 하에서 상온에서 $KMnO_4$를 이용하여 하이드록실기로 개질된 MWCNT, BYK-9077 분산제를 이용한 MWCNT를 사용하였다. 분석 결과 MWCNT의 PS/THF 용액 내에서의 분산 안정성은 최종 제조되어진 복합재료의 열 및 전기전도도 특성 향상에 중요하게 기여하였다. PS/3 wt% pristine MWCNT에 비하여, 특히 분산제 BYK-9077을 사용한 경우에는 열전도도가 9.7% 및 전기전도도가 30~50% 향상되는 결과를 얻었다.

• Bulletin of the Korean Chemical Society
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• 제31권12호
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• pp.3593-3599
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• 2010

In an original effort, this lab attempted to employ polystyrene nanoparticles as a template for the synthesis of ordered and highly porous macroporous $SiO_2$ thin films, utilizing their high combustion temperature and narrow size distribution. However, polystyrene nanoparticle thin films were not obtained due to the low interaction between individual particles and between the particle and silicon substrate. However, polystyrene-polyacrylic acid (PS-AA) colloidal particles of a core-shell structure were synthesized by a one-pot miniemulsion polymerization approach, with hydrophilic polyacrylic acid tails on the particle surface that improved interaction between individual particles and between the particle and silicon substrate. The PS-AA thin films were spin-coated in the thickness ranges from monolayer to approximately $1.0\;{\mu}m$. Using the PS-AA thin films as sacrificial templates, macroporous $SiO_2$ thin films were successfully synthesized by vapor deposition or conventional solution sol-gel infiltration methods. Inspection with field emission scanning electron microscopy (FE-SEM) showed that the macroporous $SiO_2$ thin films consist of interconnected air balls (~100 nm). Typical macroporous $SiO_2$ thin films showed ultralow refractive indices ranging from 1.098 to 1.138 at 633 nm, according to the infiltration conditions, which were confirmed by spectroscopy ellipsometry (SE) measurements. This research shows how the synthetic control of the macromolecule such as hydrophilic polystyrene nanopaticles and silicate sol precursors innovates the optical properties and processabilities for actual applications.

• 한국응용과학기술학회지
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• 제26권3호
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• pp.306-316
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• 2009

In this study, block copolymer of polystyrene and polyethylene glycol methyl ether methacrylate(PEGMA) by ATRP(atom transfer radical polymerization) method was synthesized. 4 arm-molecule which contained halogen atom was synthesized for an initiator. With 4 arm-molecule monodispered polystyrene were synthesized by ATRP method. The molecular change of synthesized monodispersed polystyrene with respect to time was investigated and living polymer characteristic was confirmed. Block copolymer of polystyrene and polyethylene glycol methyl ether methacrylate(PEGMA) was synthesized by ATRP with macroinitiator which was synthesized from the monodispersed polystyrene(Mn=12000). The molecular weight of obtained PS-b-PEGMA was 22,000.

• Korea-Australia Rheology Journal
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• 제17권2호
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• pp.41-45
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• 2005

As an effort to explore the effective use of carbon nanotubes as a reinforcing material for advanced nano-composites with polymer matrices, multi-walled carbon nanotubes (MWNTs) were successfully incorporated into polystyrene (PS) via in-situ bulk polymerization. Various experimental techniques revealed that the covalent bonds formed between PS radicals and acid-treated carbon nanotubes are favorable resulting in an effective load transfer. The enhanced storage modulus of the nanocomposites suggests a strong possibility for the potential use in industrial applications.

• 공업화학
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• 제7권2호
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• pp.350-355
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• 1996

Poly(AA-co-EGDMA) microgel은 시크로헥산/아세톤용액에 팽윤된 폴리스티렌겔 용액중에서 침전중합 방법으로 합성하였다. Microgel을 합성함에 있어서 폴리스티렌의 농도, 가교제의 농도, 폴리스티렌과 모노머의 비율 및 용매의 성질에 따라 $0.18{\sim}0.55{\mu}m$의 입자크기로 조절할 수 있었으며, 구형의 단분산성 microgel을 합성할 수 있었다. 또한 폴리스티렌 용액의 농도가 증가함에 따라 microgel의 입자크기는 작아졌고, 가교제의 농도가 증가할 수록 입자크기는 증가하였다.

• 폴리머
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• 제39권3호
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• pp.468-474
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• 2015

고분자 재료에 전기 전도성을 부여하기 위해 그래핀 기반의 나노필러를 도입하여 전도성 나노복합재료를 제조하였다. 그래핀 나노필러는 폴리스티렌(PS) 입자와 수계 분산이 용이하도록 산화 그래핀(GO) 및 poly(styrene sulfonate)가 도포된 환원된 산화 그래핀(PSS-RGO)을 사용하였다. GO는 흑연으로부터 modified Hummers 방법으로 합성하였으며, PSS-RGO는 GO가 분산된 PSS 용액을 hydrazine monohydrate로 환원시켜 제조하였다. 라텍스 기법으로 제조한 PS/GO 및 PS/PSS-RGO 나노복합재료의 모폴로지, 유변물성 및 전기적 물성을 고찰하였다. GO 및 PSS-RGO 나노필러는 PS 매트릭스 내에 잘 분산된 모폴로지를 보여 주었다. 그래핀 나노필러 함량에 따른 유변학적, 전기적 임계점은 GO가 0.28, 0.51 wt%로 나타났고 PSS-RGO는 0.50, 1.01 wt%로 나타났다. PS/GO 나노복합재료가 우수한 전기 전도도를 보여주는 이유는 성형시의 열처리에 의해 GO가 환원되어 전기적 물성을 부분적으로 회복했기 때문으로 판단된다.