• 대한화학회지
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• 제35권1호
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• pp.16-23
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• 1991

폴리스틸렌 수지에 트리에틸렌테트라아민을 반응시켜 선형과 집게형의 킬레이트 수지를 합성하였으며, 이들 수지에 지지된 아민은 주로 적외선 스펙트럼으로 확인하였고, 전이금속이 수지에 흡착되는 속도를 측정하였다. 이 결과에서 얻어진 확산계수 및 활성화엔트로피 등이 보고된다. 흡착과정의 속도결정 단계는 입자를 통한 확산과정이다.

• Journal of Industrial and Engineering Chemistry
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• 제68권
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• pp.342-349
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• 2018

Polystyrene (PS) was coated on carbonyl iron (CI) particles via dispersion polymerization to produce core-shell structured CI/PS particles and adopted as magnetorheological (MR) material. Two MR fluids were prepared by dispersing CI/PS and CI particles in silicone oil. Their MR and tribological properties were investigated using a rheometer and a reciprocating friction and wear tester, respectively. Experimental data showed that tribological properties of MR fluid based on CI/PS particles are significantly enhanced compared to those of CI based MR fluid. Sedimentation problem of CI/PS MR fluid was also expected to be improved due to relatively lower density of CI/PS particles.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.146-146
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• 2016

Zinc Oxide (ZnO) was known as a promising material for surface acoustic wave devices, gas sensors, optical devices and solar cells due to piezoelectric material, large band gap of 3.37 eV and large exciton binding energy of 60 meV at room temperature. In particular, the alignment of ZnO nanostructures into ordered nanoarrays can bring about improved sensitivity of devices due to widen the surface area to catch a lot of gas particle. Oxygen plasma treatment is used to specify the nucleation site of round patterned ZnO nanorods growth. Therefore ZnO nanorods were grown on a quartz substrate with patterned polystyrene monolayer by hydrothermal method after oxygen plasma treatment. And then, we carried out nanostructures by adjusting the diameter of the arranged ZnO nanorods according to polystyrene spheres of various sizes. The obtained ZnO nanostructures was characterized by X-ray diffraction (XRD), Field emission scanning electron microscopy (FE-SEM).

• 멤브레인
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• 제29권1호
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• pp.61-65
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• 2019

이방성 입자는 독특한 물리적 특성 때문에 다양한 분야에서 발표되고 있다. 여기서, 이방성 도토리구조 나노 입자를 제조하기 위해 새로운 동적 상분리 방법이 도입된다. 동적 상분리 방법은 용제 증발 및 무용제에 의한 침전으로 구성된다. 하부층은 비용매 희석제로서 물을 공급함으로써 제어되며, 상부층의 상분리는 휘발성 용매의 확산 및 증발에 의존한다. 이 상태에서, 도토리 형 입자가 제조되었다. 물이 채워진 밀폐된 상자(자발적 상분리)하에서, 단분산 폴리스틸렌 입자가 합성되었다. 동적 상분리와 자발적 상분리가 공존할 때, 캡과 입자의 크기가 변경되었다. 또한, 폴리스틸렌 용액의 부피는 입자 형상에 영향을 미친다. 독특한 구조가 다양한 응용 분야에 활용될 수 있기 때문에 멤브레인 기반의 제어된 물 공급과 같은 첨단 기술이 개발되면 단분산의 도토리와 같은 입자가 제조될 수 있을 것이다.

• 폴리머
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• 제33권1호
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• pp.33-38
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• 2009

은 카바메이트 착체 화합물의 환원에 의한 무전해 도금법으로 은/폴리스티렌 비드를 제조하기 위하여 폴리스티렌 및 아민 관능기를 가지는 공중합체 비드를 제조하였다. 스티렌, divinylbenzene(DVB) 그리고 2-(N,N-dimethylamino)ethyl methacrylate (DAEMA) 단량체들을 poly(vinyl alcohol) 존재 하에서 물/메탄올을 용매로 사용하여 무유화중합을 진행하였다. 30/0$\sim$1.5/0$\sim$3 wt%의 단량체 조성을 가지는 poly(styrene/DVB/DAEMA) 비드는 구형으로 1 ${\mu}m$의 일정한 크기를 가지고 있었다. 아민 기능기를 가지는 폴리스티렌 비드의 무전해 도금은 비드의 전처리 없이 silver 2-ethylhexylcarbamate (Ag-EHCB) 복합체와 히드라진 환원제를 사용하여 메탄올 용액에서 진행하였다. 제조된 비드와 도금된 비드 표면의 형태를 SEM으로 관찰하였으며 은 도금된 비드를 분산시켜 자외선 흡수 변화 그리고 도금된 은의 성분을 XRD로 분석하였다.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.205-205
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• 2006

Adsorption behaviors of positively charged matrix (PAH) onto negatively charged probe (sulfate PS particle) were investigated using DLS (dynamic light scattering) and FPR (fluorescence photobleaching recovery) as view points of matrix and salt concentration. The system experienced sharp decrease of diffusion (flocculation) at dilute condition while the system underwent gradual decrease of diffusion above semi-dilute concentration. With FPR and viscometry experiments, we revealed the probe behaviors in polyelectrolyte solution were strongly affected by the coil overlap concentration (0.5 g/L PAH concentration).

• 한국입자에어로졸학회지
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• 제8권1호
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• pp.29-35
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• 2012

The Faraday cup electrode of different size has been developed and evaluated to investigate the diffusion effect of particles by Brownian motion in a particle beam mass spectrometer(PBMS). Particles which focused and accelerated by aerodynamic lens are charged to saturation in an electron beam, and then deflected electrostatically into a Faraday cup detector for measurement of the particle current. The concentration of particles is converted from currents detected by Faraday cup. Measurements of particle current as a function of deflection voltage are combined with measured relationships between particle velocity and diameter, charge and diameter, and mass and diameter, to determine the particle size distribution. The particle currents were measured using 5, 10, 20, 40 mm sized Faraday cup that can be move to one direction by motion shaft. The current difference for each sizes as a function of position was compared to figure out diffusion effect during transport. Polystyrene latex(PSL) 100, 200 nm sized standard particles were used for evaluation. The measurement using 5 mm sized Faraday cup has the highest resolution in a diffusion distance and the smaller particles had widely diffused.

• 한국입자에어로졸학회지
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• 제10권3호
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• pp.99-108
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• 2014

Liquid filtration by membrane filters is essential for the preparation of ultrapure water in semiconductor manufacturing processes. The separation of submicrometer particles suspended in ultrapure water with a laminated fibrous membrane filter was studied numerically and experimentally in the present work. We found that an electrical double layer around a single fiber expanded to a large extent at a low ion concentration, as in ultrapure water, and deformed toward the upstream of the fiber with increasing filtration velocity. Since an increase in the electrical double-layer thickness leads to a decrease in the electrical potential gradient, particles with the same polarity as the fiber approach the fiber more easily and are captured at a high filtration velocity. Experimental results also confirmed that the collection efficiency of polystyrene latex(PSL) particles through a PTFE filter became higher as the filtration velocity increased.

• Bulletin of the Korean Chemical Society
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• 제16권7호
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• pp.613-619
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• 1995

The influence of carrier solutions on particle retention was studied by varying surfactants and ionic strength in flow field-flow fractionation. Experiments were made with five different submicron polystyrene latex standards at three different types of surfactants and seven different ionic strengths. Departures in particle retention from the general theory were observed. At low ionic strength, it is shown that migrating sample zone is clearly lifted away from the ideal equilibrium height and that the repulsive interaction dominates between the particle and the channel wall. As ionic strength increases up to a certain level, particle retention becomes closer to the general theory. Further increase in ionic strength is shown to prolong the retention. An optimum regime of ionic strength is also suggested with the proper choice of surfactants.

• 대한기계학회논문집A
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• 제32권4호
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• pp.297-302
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• 2008

We present an electrical particle velocity profiler using particle transit time across uneven inter-gap electrodes. We measure both the particle position and velocity from the voltage signals generated by the particles passing across sensing electrodes, thus obtaining the velocity profile of the particles in a microfluidic channel. In the experimental study, we use polystyrene microparticles to characterize the performance of the electrical particle velocity profiler. The particle velocity profile is measured with the uncertainty of 5.44%, which is equivalent to the uncertainty of 5% in the previous optical method. We also experimentally demonstrate the capability of the present method for in-channel clogging detection. Compared to the previous optical methods, the present electrical particle velocity profiler offers the simpler structure, the cheaper cost, and the higher integrability to micro-biofluidic systems.