• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 한국축산식품학회 2006년도 정기총회 및 제37차 춘계 국제학술발표대회
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• pp.133-137
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• 2006

본 연구의 목적은 $\beta$-CD를 가교화 시켜 육가공 제품의 주원료인 lard에 내재하는 cholesterol을 효과적으로 제거하기 위한 최적조건 확립이다. 따라서 adipic acid로 가교화한 $\beta$-CD를 이용하여 lard에서 cholesterol을 제거하고 더 높은 효율을 찾기 위하여 실시되었다. 가교화 $\beta$-CD를 이용해 lard에서 cholesterol 제거 실험결과의 최적 조건은 lard:distilled water=1:1, 가교화 $\beta$-CD 5%, 교반온도 $40^{\circ}C$, 교반시간 10분, 교반속도 150rpm으로 실험한 결과 cholesterol 제거율이 평균 92.32%이었다. 또한 10회 재활용 결과 평균 98.04%의 재활용률을 보였으며, 8회 이후에는 유의적으로 감소하여 가교화 $\beta$-CD의 효율적인 재활용이 가능함을 시사하였다. 이 실험의 결과 가교화 $\beta$-CD로 lard의 cholesterol 제거 최적조건을 규명함으로써 콜레스테롤을 저하시킨 육가공 제품의 생산 가능성을 보였다.

• Membrane Journal
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• 제14권1호
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• pp.44-52
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• 2004

This paper concerns the development of a cationic polymeric membranes for direct methanol fuel cell. The crosslinked poly(vinyl alcohol) (PVA) membranes with poly(acrylic acid-co-maleic acid) (PAM) and hydroquinonesulfonic acid (HQSA) as the crosslinking agents were prepared according to the amount of crosslinking agents. The resulting membranes were characterized in terms of methanol permeability, proton conductivity, water content and ion exchange capacity. The methanol permeability and proton conductivity increased with increasing PAM content up to 9 wt% and then decreased. This trend is considered the effect of the cross linking rather than the introduction of hydrophilic groups. When the HQSA contents were varied, no interesting increases of proton conductivity, water content and ion exchange capacity were found.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 한국축산식품학회 2005년도 정기총회 및 제35차 춘계 학술 발표대회
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• pp.169-172
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• 2005

본 연구의 목적은 ${\beta}-CD$를 가교화 시켜 육가공 제품의 주원료인 lard의 cholesterol을 효과적으로 제거하기 위한 최적조건 확립이다. 따라서 adipic acid로 가교화한 ${\beta}-CD$를 이용해 lard에서 cholesterol을 제거하고 더 높은 효율을 찾기 위하여 실시되었다. 가교화 ${\beta}-CD$를 이용해 lard에서 cholesterol 제거 실험결과의 최적 조건은 lard : distilled water=1:1, 가교화 ${\beta}-CD$ 5%를 첨가, 교반온도 $40^{\circ}C$, 교반시간 10분, 교반속도 150rpm으로 실험한 결과 cholesterol 제거율이 평균 81.6%이었다. 이 실험의 결과 가교화 ${\beta}-CD$로 lard의 cholesterol 제거 최적조건을 규명하고 이는 콜레스테롤을 저하시킨 육가공 제품의 생산 가능성을 시사하였다.

• Korean Chemical Engineering Research
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• 제58권4호
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• pp.618-623
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• 2020

Spherical phenolic resin beads were synthesized by suspension polymerization at 98 ℃ from phenol, ortho-cresol, formaldehyde, with triethylamine as a basic catalyst, and spherical phenol-cresol copolymer resin beads with relatively low crosslinking density as well. Phenol reacts with formaldehyde at two ortho- and one para- positions to form a crosslinked structure, but ortho-cresol instead of phenol reduces the crosslinking density during copolymerization due to the methyl group at a ortho- position. As a result, spherical phenol-cresol copolymer beads showed more shrinkage with decreasing apparent density compared to the spherical phenol beads when carbonized at 700 ℃ under nitrogen. As the molecular weight of the cresol oligomer increases, the pore radius of the carbonized copolymer beads decreases, which is consistent with the density and shrinkage results. It was confirmed that the characteristics such as density decrease, shrinkage, yield and so on during carbonization can be controlled by controlling the degree of crosslinking of the spherical phenolic resin particles with cresol.

• Journal of the Korean Society of Clothing and Textiles
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• 제25권10호
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• pp.1738-1744
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• 2001

본연구의 목적은 반응성 염료를 이용한 텐셀섬유의 피브릴화 조절 효과를 표면 형태, 감량율, 역학적 성질 및 태의 변화의 측면에서 고찰하는데 있다. 반응성 염료에 의한 가교는 섬유의 비결정 영역의 구조를 변화시켜 피브릴화를 억제하였으며 또한 효소의 작용에 영향을 주어 감량율을 감소시켰다. 반응성 염료에 의한 가교는 역학적 성질 중 특히 전단강성, 압축에너지, 압축레질리언스를 증가시켰다. 염색후 효소처리한 시료는 다른 시료보다 numeri와 fukurami 값이 높아 더 나은 종합태를 보였다. 공정순서에 따라 약간씩 차이가 있는 촉감을 나타냈다.

• Membrane Journal
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• 제28권3호
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• pp.205-213
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• 2018

In this study, cross-linked membrane were successfully prepared by using brominated PPO (Br-PPO) as the main polymer chain. Chitosan and quaternary ammonium modified chitosan (QA-chitosan) was used as the cross linking agents. The cross linked membranes were post-functionalized by using trimethylamine solution. The degree of cross linking was also controlled by varying the ratio of cross linking agent. The applicability of the cross-linked membrane (A-PPO + chitosan, A-PPO + QA-chitosan) as ion exchange membranes was verified through various characterization techniques. The cross-linked membrane using QA-chitosan as cross linking agent was found to be better in performance than the membrane using pristine chitosan cross linking agent. As the percentage of QA-chitosan increased, the ion exchange capacity from 1.18 meq/g to 1.53 meq/g and water uptake from 21.6% to 42.2% was improved.

• Polymer(Korea)
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• 제29권4호
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• pp.344-349
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• 2005

Polyurethanes(PUs) were synthesized by reaction of isophorone diisocyanate, acetylbutyl citrate, and 3 types of polycaprolactone diol. Their structures were confirmed by FT-IR and NMR spectrometer. And, their thermal and mechanical properties were measured by TGA ud UTM. The effective network chain lengths ($\bar{M}_c$), measured by compressive modulus apparatus, were about $8000\~24000$ g/mol. As crosslinking density and amount of hard segment increased, tensile strength increased and elongation decreased. As the crosslinking density of PUs increased, thermal property inproved. When the ratio of NCO/OH is 1.1, maximum crosslinking density was achieved.

• Elastomers and Composites
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• 제49권3호
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• pp.199-203
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• 2014

Terpolymer syrups were photopolymerized from 2-ethylhexyl acrylate, 2-hydroxylethyl acrylate and isobornyl acrylate to prepare acrylic pressure sensitive adhesives (PSAs). After polymerization, various crosslinkers as 1,6-hexanediol diacrylate (HDDA), poly (ethylene glycol) diacrylate (PEGDA, Mn = 250, 575, and 700) were added and then UV-irradiated to prepare the semi-IPN type PSAs. Their adhesion performance and storage modulus (G') were strongly dependent on their chemical structure and molecular weight of the crosslinkers. Optical properties such as transmittance (> 92.5 %), haze (< 1.0 %) and color-difference (< 0.3) of PSAs samples were not affected by crosslinker types used in this study.

• Elastomers and Composites
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• 제33권4호
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• pp.281-289
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• 1998

Tensile properties including Young's modulus and tear strength were measured for four different rubber compounds; natural rubber(NR), styrene-butadiene copolymer(SBR), ethylene-propylene diene monomer (EPDM), and brominated isobutylene-p-methyl-styrene copolymer(BIMS) as a function of temperature and degree of cure. To see the effect of over cure, a measurement was made of the tensile strength and swelling behavior of the over-cured rubber compounds. Young's modulus, E, was found to have linear dependency on the degree of cure for all rubber compounds. EPDM and BIMS showed the highest and lowest slopes, respectively. The slope of NR and SBR lay between EPDM and BIMS. Tear strength, Gc, decreased in the order of NR>BIMS>SBR>EPDM. As the cure time was extended the degree of cure of NR and SBR decreased, while that of BIMS increased. EPDM showed little change in the degree of cure.

• Journal of Sericultural and Entomological Science
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• 제44권1호
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• pp.37-41
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• 2002

The attaching treatment of sericin onto polyester fiber was attempted to improve its sanitary properties. Generally, sericin, a gummy material covering the outer layer of silk filament, is subjected to be removed during degumming process of silk textile process. For this study, sericin particle dissolved within the degumming waste water could be collected by sedimentation of polyaluminium chloride. It was revealed that sericin particle were attached onto the surface of polyester fiber evenly by treatment of glutaraldehyde, a crosslinking agent. A frictional static charge of the treated polyester fabric could be improved, while its hygroscopic property was little changed.