• 반도체디스플레이기술학회지
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• 제15권1호
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• pp.12-16
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• 2016

Toluene-free pressure sensitive adhesives were synthesized by using butyl acrylate (BA), 2-hydroxy ethyl acrylate, methyl methacrylate, acrylic acid (AA) as monomers and ethyl acetate as a solvent. The polymerization recipes were designed by changing 1, 3, 5 part per hundreds monomer (phm) of AA content on the basis of 100 BA parts. Two crosslinking agents, ethyl glycol diglycidyl ether (EDGE) and isophorone diisocyanate (IPDI) were added to the synthesized polymers to increase adhesion due to crosslinking. In the measurement of properties, holding power, peel strength, and initial tackiness increased with AA content due to crosslinking between carboxyl group in AA and epoxy group in EDGE and isocyanate group in IPDI. In the comparison of two crosslinking agents, EDGE showed better in the three properties than IPDI by better reaction of epoxy group of EDGE to carboxyl group of AA.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1996년도 추계학술대회
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• pp.3-6
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• 1996

The Ultra-high molecular weight polyethylene (UHMWPE) is exclusivity used as the articulation component with metal or ceramic materials in artificial joint prosthesis because of its good mechanical properties. In the long term however, wear of UHMWPE causes complex problems and hence causes loosening of He prosthesis. In this study, we tried to enhance the wear property of UHMWPE by attaching a hydrophilic graft on the UHMWPE surface and by improving surface hardness without deteriorating the mechanical properties of UHMWPE. This was achieved by ion implantation and by ${\gamma}$-irradiation to the surface in acrylic acid solution and by photo-polymerization in divinylbenzen (DVB), diallysophthalate (DAIP) solution. The wear test was performed by a wear testing machine of ball-on-disk type devised by the authors. The UHMWPE with hydrophlic surface and increased surface hardness developed by above treatments showed less volumetric wear.

• Macromolecular Research
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• 제16권2호
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• pp.134-138
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• 2008

A novel acrylol borate was designed and synthesized by reacting acrylate monomer and boric acid. The obtained acrylol borate was used as both gelator and anion receptor for the liquid electrolyte in a lithium secondary battery. It was found that the ionic conductivity of the gel polymer electrolyte (GPE) was as high as that of the liquid electrolyte, and the thermal stability of GPE was increased when only 2 wt% acrylol borate was incorporated into the liquid electrolyte. These results suggest that acrylol borate can be used as an effective additive to enhance the thermal stability of the electrolyte without adversely affecting its conductivity. It is believed that the strong complex formation between boron in the gelator and the anion of the salt is responsible for the enhanced thermal stability of the electrolyte solution and the increased ionic conductivity.

• Macromolecular Research
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• 제16권4호
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• pp.373-378
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• 2008

A simple chemical fixation method for the fabrication of layer-by-layer (LbL) polyelectrolyte multilayer (PEM) has been developed to create a large area, highly uniform film for various applications. PEM of weak poly-electrolytes, i.e., polyallylamine hydrogen chloride (PAH) and poly(acrylic acid)(PAA), was assembled on polymer substrates such as poly(methyl methacrylate)(PMMA) and polycarbonate (PC). In the case of a weak polyelectrolyte, the fabricated thin film thickness of the polyelectrolyte multilayers was strongly dependent on the pH of the processing solution, which enabled the film thickness or optical properties to be controlled. On the other hand, the environmental stability for device application was poor. In this study, we utilized the chemical fixation method using glutaraldehyde (GA)-amine reaction in order to stabilize the polyelectrolyte multilayers. By simple treatment of GA on the PEM film, the inherent morphology was fixed and the adhesion and mechanical strength were improved. Both surface tension and FT-IR measurements supported the chemical cross-linking reaction. The surface property of the polyelectrolyte films was altered and converted from hydrophilic to hydrophobic by chemical modification. The possible application to antireflection coating on PMMA and PC was demonstrated.

• 펄프종이기술
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• 제29권3호
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• pp.17-25
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• 1997

Natural water-soluble polymers such as starch, casein and carboxy methyl cellulose(CMC) have been limited in their uses. However, the proper water retention of coating colors can not be obtained without addition of these polymers. Furthermore, the coating runnability and the physical properties of coated paper were not also satisfied. Therefore, the objective of this study was to synthesize the water retention and flow modifiers which can improve the water retention and flow properties of coating colors. We have measured physical properties of flow modifiers and coating colors which included flow modifiers. The viscosity of flow modifiers was very low at acid pH, and rapidly increased at about pH 7, and gradually reached to equilibrium at alkali pH. Such an increase comes from the molecular weight of flow modifiers and the amount of acrylic and methacrylic acids. The viscosity of coating color containing the flow modifiers was lower than that containing CMC. However, both of them had little difference in water retention. The water-phase viscosity of synthetic modifier containing coating color was either higher or similar compared to that of CMC containing coating color. The high shear viscosity of coating colors was low. Therefore, it can be concluded that the synthetic flow modifiers are very useful for improvement of flow properties and water retentions.

• 방사선산업학회지
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• 제4권3호
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• pp.271-276
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• 2010

Epoxy resin has wide application in various industrial fields because of their good mechanical strength, superiority adhesion and low shrinkage etc. And the typical curing method for epoxy resins is thermal and press compaction. However, a curing method was used electron beam process in this study. Epoxy acrylate was fabricated from mixture of epoxy, acrylic acid, tetraphenylporphyrin (TPP) and hydroquinone monomethyl ether (MEHQ) with mole ratios. Then electron beam irradiation effect on the curing of the epoxy acrylate resin was investigated various absorption dose in nitrogen atmospheres at room temperature. The dynamic mechanical and thermal properties of the irradiated epoxy acrylate resins were characterized using dynamic mechanical analysis (DMA) and thermogravimetric analyzer (TGA). And the tensile and flexural strength were measured by an universal tensile machine (UTM).

• 통합자연과학논문집
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• 제9권1호
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• pp.16-22
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• 2016

The optical and physical and characteristics of hydrogel ophthalmic lens polymerized with addition of 2,6-difluoropyridine, SiPc(silicon 2,9,16,23-tetra-tert-butyl-29H31H-phthalocyanine dihydroxide) and nanodiamond in the basic hydrogel material were evaluated. In particular, the utility of 2,6-difluoropyridine, SiPc and nanodiamond as a hydrogel ophthalmic lens material was investigated. 2,6-difluoropyridine, SiPc and nanodiamond were used as additives. And also, 2-hydroxyethyl methacrylate, acrylic acid, methyl methacrylate and a cross-linker EGDMA were copolymerized in the presence of AIBN as an initiator. The refractive index of 1.4348~1.4361, water content of 33.30~34.02%, UV-B transmittance of 4.77~67.50%, UV-A transmittance of 1.45~89.19% and visible transmittance of 32.12~92.21% were obtained. The results of hydrogel lens containing 2,6-difluoropyridine (add 5%) showed antibiosis for staphylococcus aureus. The produced copolymer is suitable for hydrogel soft ophthalmic lenses with antibiotic and anti-UV effect.

• 접착 및 계면
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• 제8권1호
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• pp.8-14
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• 2007

폴리우레탄에 아크릴기가 도입된 poly(urethane-methyl methacrylate) 혼성 에멀젼 코팅 수지는 플라스틱 코팅 수지로써 열적, 기계적 물성 및 내화학성을 제어할 수 있다. 이에 본 연구에서는 프리폴리머 혼합 공정과 무유화 중합 방법을 이용하여 수분산된 poly(urethane-methyl methacrylate) 혼성 에멀젼을 합성하였다. 즉, 폴리우레탄 프리폴리머 합성 단계에서 2,2-bis (hydroxymethyl) propionic acid (DMPA)을 투입하고 methyl methacrylate (MMA) 단량체를 투입한 후, triethylamine (TEA)을 이용하여 DMPA의 카르복실기를 중화시켜 친수성기를 도입하였다. 이를 수분산시켜 안정한 액적을 형성시킨 후, 사슬연장 및 무유화 중합 방법에 의해 합성반응을 진행하였다. 이때 제조공정 조건 및 아크릴계 단량체의 함량을 달리하여 poly(urethane-methyl methacrylate) 혼성 에멀젼의 다양한 샘플을 얻으며, 수분산 샘플의 물성(인장강도, 점도, 부착성 등) 및 코팅필름의 특성을 평가 비교하였다.

• 공업화학
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• 제5권3호
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• pp.443-450
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• 1994

Polyacrylic acid를 NaOH와 $NH_4OH$로 중화시켜 중화도가 다른 polyelectrolyte를 만든 후, 수용액 상에서 ethylene glycol diglycidyl ether(EGDE)로 가교시켜 안정한 상태의 젤을 얻었다. 안정한 젤이 얻어지는 가장 작은 polyelectrolyte의 농도인 $C_{gel}$은 polyelectrolyte의 extended from에도 불구하고 비슷한 분자량의 중성 고분자의 간과 비슷하였다. 전해질 고분자에 대한 scaling이론에 의하면 semi-dilute영역에서의 전해질 고분자용액은 분자량 의존성이 없어야 함에도 불구하고 gelation결과는 중성 고분자와 흡사한 분자량 의존성을 보이며 entanglement 농도인 $C^{**}$와 비교했을 때에도 $C_{gel}$은 훨씬 큰 값을 갖는다. 이는 고분자 전해질의 농도가 진해질수록 용액의 이온세기가 증가하여 extended from에서 coil form으로 변화되기 때문으로 보인다. 고분자 전해질의 중화도에 따른 gelation은 100% 중화된 시료의 $C_{gel}$값과 분자량 의존성에 있어 거의 비슷한 경향을 보이며 이는 고분자 전해질의 conformation변화가 이온세기에 상당히 민감함을 보여 준다. 고분자 전해질 수용액에 추가로 저분자량의 염을 가하면 고분자의 용액 속에서의 크기가 더욱 축소하여 더 큰 $C_{gel}$값을 보인다.

• 공업화학
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• 제1권2호
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• pp.197-206
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• 1990

이미다졸린 핵에 유연성을 부여하기 위하여 소수성기로서 behenic acid를 선택하고 3종류의 polyalkylene polyamine 과 반응시켜 1, 2-이치환 이미다졸린 화합물인 1-behenoyl-aminoethyl-2-heneicosylimidazoline(BHI), 1-behenoylbis(aminoethyl)-2-heneicosylimidazoline(BBI) 및 1-behenoyltris(aminoethyl)-2-heneicosylimidazoline(BTI)을 합성하였다. 동 화합물들을 4급화 시켜 1, 2-이치환 이미다졸린 염화물인 1-behenoylaminoethyl-1-glycidyl-2-heneicosylimidazolinium chloride(BHIC), 1-behenoylbis(aminoethyl)-1-glycidyl-2-heneicosylimidazolinium chloride(BBIC) 및 1-behenoyltris(aminoethyl)-1-glycidyl-2-heneicosylimidazolinium chloride(BTIC)를 합성하였다. BHI, BBI 및 BTI 합성의 최적조건은 $210^{\circ}C$에서 8시간이었으며 BHIC, BBIC 및 BTIC 합성에서 BHIC는 BHI-epichlorohydrin의 mole ratio가 1:1.3, BBIC와 BTIC는 mole ratio가 1:1.5 이상일 때 완전 4급화가 이루어졌다. BHIC, BBIC 및 BTIC에서 유연제 BHICS, BBICS 및 BTICS를 제조한 후 아크릴 섬유에 유연처리를 하여 유연성을 측정한 결과 양호한 유연제임이 밝혀졌다.