• Journal of the Korean Wood Science and Technology
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• 제22권1호
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• pp.80-84
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• 1994

The orientation of bezene ring in latex film was investigated with raman spectroscopy. The benzene ring of anionic latex ran parallel with the film surface of latex, whereas that of amphoteric latex did not. Consequently, it showed the possibility of interactions or interrelations between the orientation of benzene ring and ink, contact angle, printability and so on.

• Journal of the Korean Wood Science and Technology
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• 제22권1호
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• pp.85-90
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• 1994

The flow properties of binder latices for paper coating were investigated, together with dynamic viscoelastic properties of latex films and electron micrographs of latices, under various conditions. The amphoteric latex, binder pigment latex and anionic latex were used in this work. The amphoteric latex has both anionic and cationic functional group on its surface. The binder-pigment with a core-shell structure has dual functions : plastic pigment and binder. The low shear viscosity of binder latices and clay slurry were measured with Brookfield vis cometer. At low-shear rates. the viscosity decreased with increasing particle size of latex. On the amphoteric latex surface, the carboxyl groups are assumed to be fully dissociated over the region of pH 9~12, but the density of negative groups seems to be increased because of the gradual decrease in the degree of dissociation of amino groups. Since the apparent particle size of latex increases with surface charge, the electroviscous effect can be observed. On the anionic latex surface, the charge density is assumed to be nearly constant above pH 8. However, below pH 8 the coagulation of particles could be observed probably because of the decrease in the charge density.

• Elastomers and Composites
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• 제33권2호
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• pp.83-92
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• 1998

SBR latex, polyurethane latex and epoxy latex were mixed with polyvinyl acetate emulsion in 0~15% (wt.%). For the mixtures, the viscous properties were examined. The viscosity was influenced by the dispersed phase and the chain structures of polymer, and decreased with the rising of temperatures. The viscosity was increased with mixing of epoxy latex, but decreased with addition of SBR latex or polyurethane latex. Thixotropic index was influenced on the size of micelle and hydrogen bond. The thixotropic index was increased with mixing of epoxy latex or polyurethane latex within 5%, but keep up equality over that. The thixotropic index was decreased with mixing of SBR latex within 5%, but keep up equality over that. The relative viscosity were influenced on the activity of molecule and the interference of dispersed phases, was increased with the rising of temperatures. The relative viscosity was decreased with mixing of epoxy latex, but increased with mixing of SBR latex or polyurethane latex.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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• pp.757-762
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• 2002

This study focused on the investigation of durability of latex modified concrete in the points of surface scaling resistance as cement types variated and latex content variated such as 5%, 10%, 15%, and 20%. An increasing the amount of latex produced concrete with increased flexural strength, but with slightly lower compressive strength. The increase in flexural strength might be attributed to the latex films between the hydrated cement and aggregates, and the decrease in compressive strength to the flexibility of the latex component named by Butadiene. The surface scaling resistance test was used to evaluate the durability of latex-modified concretes and rapid setting latex-modified concretes. The surface scaling resistance of LMC was quite good comparing to conventional concrete. Further, surface scaling resistance of RSLMC was improved with increasing the latex content.

• 산업기술연구
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• 제21권B호
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• pp.317-324
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• 2001

This study focused on the investigation of strength development and permeability of LMC(Latex Modified Concrete) and RSLMC(Rapid-Setting Cement Latex Modified Concrete) as the latex content, cement types and w/c ratio changed. The compressive strength of latex modified concrete decreased slightly and the flexural strength increased quitely at 15% of latex content. This may be due to the flexibility of latex filled in voids and interconnections of hydrated cement and aggregates by a film of latex particles, respectively. The permeability test results showed that the permeability of LMC was considerably lower than that of conventional concrete. Results of chloride permeability test, for RSLMC indicated very low at an early age caused by the early formation of needle-shape ettringites and latex film.

• 대한간호
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• 제37권2호
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• pp.87-92
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• 1998

Immdeiate hypersensitivity reactions to natural rubber and latex products pose a significant threat to patients, healthcare workers, and the general population. The purpose of this study is to summarize the clinical syomptoms of latex rubber allergy and provide guidelines for the management of latex allergy. Contact dermatitis from the nearly constant use of latex gloves during the workday has become a real problem for many health care professionals. Moreover, the patient who come in contact with these gloves or with other latex-containing equipment may show reactons. Far worse than skin problems is life-threatening anaphyaxis, which can be the first indication that a person has latex sensitivity. In conclusion, nurses shold know the latex precautions such as risk factors, adverse reactons to latex, emergent treatment and so on.

• Korean Chemical Engineering Research
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• 제50권6호
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• pp.1076-1081
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• 2012

라텍스 개질 콘크리트의 혼화용 라텍스를 개발할 목적으로 carboxylated styrene butadiene 라텍스를 이단계 유화중합법으로 제조하고 콘크리트에 적용하는 실험을 수행하였다. 음이온 유화제로는 sodium dodecylbenzene sulfonate와 sodium salt of lauryl sulfate를 선정하였고, 라텍스 안정제로는 nonylphenoxy poly(ethyleneoxy) ethanol 계열의 동족체들(n=10, 20, 40)을, 그리고 potassium persulfate와 sodium bisulfite를 redox 개시제로, $Na_2HPO_4$와 $K_2CO_3$를 전해질로 각각 사용하였다. 중합안정성에 대한 음이온 유화제의 종류와 사용량의 영향 및 입자크기의 전해질 농도 의존성을 실험적으로 고찰하여 LMC용 라텍스 제조에 적합한 중합처방을 제시하였다. 이 중합처방으로 제조한 라텍스의 LMC 용도에 대한 적용성을 시험한 결과, 슬럼프와 공기량은 한국도로공사의 품질기준을 충족하며, 역학적 물성시험 결과에서는 28일간 경화시킨 시편의 압축강도와 휨강도가 품질기준보다 각각 39.6, 87.3% 더 높은 증진효과가 발현됨을 확인하였다.

• 응용통계연구
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• 제11권1호
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• pp.41-51
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• 1998

응용통계연구 편집위원회에서는 1997년 9월부터 한글LATEX을 이용하여 편집된 논문만을 게재하기로 방침을 정하고 통일된 논문 체제 및 양식을 구현하고자 한글LATEX 스타일 파일 KJAS.STY를 개발하였다. 본고에서는 스타일 파일 KJAS.STY를 이용하여 한글LATEX으로 논문 작성하는 방법을 소개한다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 가을 학술발표회논문집(I)
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• pp.191-196
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• 2000

This study was focused on the investigation of permeability of latex modified concrete as the latex content variated such as 5%, 10%, 15%, and 20%. The rapid chloride permeability test was used to evaluate the relative permeability of latex-modified concretes and conventional concretes. The results showed that the permeability of latex-modified concretes was considerably lower than conventional concretes tested, which may be due to the latex filled in voids and interconnections of hydrated cement and aggregates by a film of latex particles.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.1023-1028
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• 2001

This study focused on the investigation of strength development and permeability of LMC(latex modified concrete) and RSLMC(rapid-setting cement latex modified concrete) as the latex content, cement types and w/c ratio variated. The compressive strength of latex modified concrete decreased slightly and the flexural strength increased quitely at the latex content of 15%. This may due to the flexibility of latex filled in voids and interconnections of hydrated cement and aggregates by a film of latex particles, respectively. The permeability test results showed that the permeability of LMC was considerably lower than that of conventional concrete. In the RSLMC's tests of permeability to chloride ion indicated very low permeability at an early age, which nay be due to the early formation of needle-shape ettringites and latex film.