• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2006년도 학술발표회 발표논문집
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• pp.431-434
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• 2006

폴리머 라텍스의 탄화와 메탄-질소 혼합가스의 CVD법으로 Carbon whisker를 가진 활성탄막을 개발하였다. 이 막의 PMMA 현탁물질 여과실험과 실제의 현탁물질과 용존유기물을 함유한 오래된 수도관으로부터 얻어진 적수여과실험 결과, Carbon whisker의 유무가 fouling에 의한 막의 flux를 억제하는 것으로 밝혀져, 실제의 정수공정에의 응용 가능성을 보였다.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2007년도 추계학술발표논문집
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• pp.171-178
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• 2007

• 한국도로학회:학술대회논문집
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• 한국도로학회 2000년도 학술발표회 논문집
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• pp.117-123
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• 2000

• 산업기술연구
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• 제22권A호
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• pp.193-200
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• 2002

Drying shrinkage cracking which may be caused by the relatively large specific surface IS a matter of grave concern for latex modified concrete(LMC) overlay and rapid-setting cement latex modified concrete(RSLMC) overlay. LMC and RSLMC were studied for field applications very actively in terms of strength and durability in Korea. However, there were no considerations in drying shrinkage. Therefore, the purpose of this dissertation was to study the drying shrinkage properties of LMC and RSLMC with the main experimental variables such as cement types(ordinary portland cement, rapid setting cement), water-cement ratios and curing days at a same controlled environment of 60% of relative humidity and $20^{\circ}C$ of temperature The drying shrinkage for specimens was measured with a digital dial gauge of Demec. The test results showed that the drying shrinkage of LMC and RSLMC were considerably lower with low water-cement ratio, respectively This might be attributed to the interlocking of hydrated cement and aggregates by a film of latex particles, water retention due to hydrophobic, and colloidal properties of the latexes resulting in reduced water evaporation.

• 한국콘텐츠학회논문지
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• 제13권3호
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• pp.43-53
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• 2013

본 논문은 스톱모션 애니메이션 제작에 실제로 사용 가능한 수준의 완성도 높은 퍼핏을 제작하기 위한 공정을 연구 주제로 하며 특히 그 핵심 과정이라 할 수 있는 몰드 제작과 캐스팅 과정을 자세히 다루고 있다. 단순 복제를 목적으로 하는 일반 몰드와 달리 내부에 아마추어를 정확히 고정시킬 수 있고 캐스팅 재료를 안정적으로 주입하거나, 고열의 오븐에 굽는 과정 등이 수차례 반복되는 캐스팅 작업을 견뎌낼 수 있도록 내열성과 내구성을 보강한 고강도 플라스터 몰드와 이중 구조의 재킷 몰드, 폼 라텍스를 재료로 한 캐스팅 과정을 소개한다. 실제 작업 과정에서 예상되는 문제점이나 전문 제작자들의 노하우, 재료 구매처 등을 포함한 작품 제작에 직접적인 도움이 되는 정보를 제공한다.

• 한국응용과학기술학회지
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• 제21권2호
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• pp.132-139
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• 2004

Film forming behavior of monodispersed model composite latexes with particle size of 190 nm, which consist of n-butyl acrylate as a soft phase monomer and methyl methacrylate as a hard phase monomer with different morphology was examined. Five different types of model latexes were used in this study such as random copolymer particle, soft-core/hard-shell particle, hard-core/soft-shell particle, gradient type particle, and mixed type particle. The film forming behavior was evaluated using pseudo on-line measurements of the cumulative weight loss, the UV transmittance, and the tensile fracture energy. Each stages of film formation I, II were not sensitive to the morphology of model latexes, but stage-ill was largely dependent on the morphology of model latexes. The chain mobility of polymer which composed the shell component was found to dominantly determine the behavior of film forming stage-III.

• 산업기술연구
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• 제24권A호
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• pp.165-171
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• 2004

Latex modification of concrete provides the material with higher flexural strength, as well as high bond strength and reduced water permeability. However, If the thermal expansion properties of overlay concrete (latex-modified concretes) are big different from that of substrate (ordinary portland cement concrete), these would cause a big interfacial stresses and result in premature failure. Therefore, the purposes of this study were to investigate thermal expansion characteristics of latex-modified concrete with cement types. The result of thermal expansion showed the coefficient of thermal expansion of concretes increased with latex inclusion. The coefficient of thermal expansion of RSLMC was a little smaller than that of LMC, which might be due to the finer cement grain, compacter internal, and stiffer properties of concrete. However, the coefficients of LMC and RSLMC were quite similar to that of ordinary cement concrete. Thus, this would not cause an interfacial stresses and will enable to ensure long-term performance of concrete bridge deck overlays.

• 한국치위생학회지
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• 제9권3호
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• pp.369-379
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• 2009

This study investigated the polymerization inhibition effect of latex gloves on addition silicone impression material. Three different kinds of addition silicone impression materials and a natural latex gloves were used in this study. The results were as follows. 1. Compared to the control group, all of those three kinds of impression materials took longer curing time in order of unwashed, alcohol and washed group, on the other hand, degloving group had shorter curing time than control group(p<0.05). 2. By the type of impression materials, there was no significant difference observed between Exafine and Twinz in ungloved group, Exafine and Imprint II in unwashed group, and Exafine and Twinz in degloving group(p>0.05). 3. The degree of polymerization at 6 minutes after mixing impression materials was evaluated by dividing its range into score 1 to 5. All of the impression materials got score 5 in control group and degloving group, which implies perfect polymerization. In unwashed group, most of them appeared to be score 2 while score 3 were most frequently observed in alcohol group and score 4 in washed group. Thus each group showed differences in the degree of polymerization(p<0.05).

• 산업기술연구
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• 제23권A호
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• pp.157-163
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• 2003

The properties of mechanics and durability of LMC have been performed actively. However, little studies on analysis and properties of thermal expansion has been on the temperature variation. Especially, the low of bonding strength and tensile cracking are caused by difference of thermal expansion between LMC and the substrate concrete. Therefore, this study focused on effect of thermal expansion behavior and properties of LMC according to temperature variation. To identify the property of thermal expansion of LMC, tests of modulus of thermal expansion were carried out at 28 days after casting specimen, subjected to temperature variation between $10^{\circ}C$ and $60^{\circ}C$. The results of this study showed the modulus of elastic of LMC was similar to that of ordinary portland concrete(OPC). It means that stresses caused by difference of modulus of elastic did not occur on interface between LMC and existing concrete. The modulus of thermal expansion of LMC had a little smaller than that of OPC. The modulus of thermal expansion of polymer modified concrete is generally larger than OPC, but the result of this test is disagree with the fact, which may be due to the humidity evaporation difference and aggregate properties.

• 산업기술연구
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• 제27권A호
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• pp.103-110
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• 2007

Concrete is a material that will crack during its service life by its very nature. For bridge decks this is especially significant as these cracks allow accelerated ingress of chlorides and the subsequent corrosion of the reinforcing steel and deck deterioration. Very-early strength latex-modified concrete (below ; VES-LMC) was developed in order to realize early-opening-to-traffic bridge deck concrete. Although there has been little research to document the degree of cracking in VES-LMC overlay, there has been a general perception among highway agencies that overlay cracking of VES-LMC, particularly early-age cracking, is a one of problems which should be solved. The purpose of this study was to analyze the cause of map, transverse and longitudinal cracking in VES-LMC and to provide a control methods for minimizing the occurrence of cracks. The proposed prevention against map and transverse cracking was verified by field applications. VES cement was modified, the unit cement contents was reduced into $360kg/m^3$ from $390kg/m^3$, the maximum size of coarse aggregate was increase into 19mm from 13mm, wire mesh and steel fibers were incorporated in concrete mixture.