• 한국응용과학기술학회지
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• 제13권1호
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• pp.47-54
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• 1996

Cinnamoyl ester(PGEFC) of poly(phloroglucinol-formaldehyde) glycidyl ether which has photosensitive functional group was prepared to apply to photoresist. Photosensitivity of PGEFC was estimated by the solubility difference in organic solvent before and after exposure to light. The yield of residual film was calculated by immersing the sample-coated quartz plates in the solvent which was used in coating. The yield of the residual film which was closely related to the sensitivity of the film, was affected by the degree of polymerization of the backbone resin, sensitizers and their concentration. The sensitivity was depended upon the degree of polymerization. Most of effective sensitizer for PGEFC among the sensitizers was 2, 6-dichloro-4-nitroaniline.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2008년도 춘계학술대회
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• pp.177-177
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• 2008

• 폴리머
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• 제36권1호
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• pp.65-70
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• 2012

글리시딜메타크릴레이트(GMA)의 플라즈마 유도 그래프트 공중합을 통해 기재로 사용한 평판형 폴리프로필렌 위에 에폭시 그룹을 도입하였다. 그래프트 공중합은 에멀젼 공중합법을 적용하였고, 기존의 용액 공중합과 비교하여 그 효과를 확인하고자 하였다. 대기압 플라즈마 처리 조건은 RF power 200 W, 처리시간 30초, Ar 기체 유속 6 LPM으로 고정하였고, 처리 후의 대기 중 노출시간 역시 5분으로 고정하였다. 중합반응에서는 GMA의 농도, 반응온도, 반응시간에 따라 표면 그래프트도의 변화를 최적화하였다. 그 결과, GMA 농도 12%, 반응온도 $90^{\circ}C$, 반응시간 5시간으로 중합하였을 때 가장 높은 그래프트도를 나타내었다. 분석 결과, 같은 반응조건 하에서 에멀젼 중합이 용액 중합에 비하여 더 많은 에폭시 그롭 도입에 효과적임을 확인하였다.

• Restorative Dentistry and Endodontics
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• 제39권4호
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• pp.310-318
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• 2014

Objectives: This study examined the influence of the resin thickness on the polymerization of silorane- and methacrylate-based composites. Materials and Methods: One silorane-based (Filtek P90, 3M ESPE) and two methacrylate-based (Filtek Z250 and Z350, 3M ESPE) composite resins were used. The number of photons were detected using a photodiode detector at the different thicknesses (thickness, 1, 2 and 3 mm) specimens. The microhardness of the top and bottom surfaces was measured (n = 15) using a Vickers hardness with 200 gf load and 15 sec dwell time conditions. The degree of conversion (DC) of the specimens was determined using Fourier transform infrared spectroscopy (FTIR). Scratched powder of each top and bottom surface of the specimen dissolved in ethanol for transmission FTIR spectroscopy. The refractive index was measured using a Abbe-type refractometer. To measure the polymerization shrinkage, a linometer was used. The results were analyzed using two-way ANOVA and Tukey's test at p < 0.05 level. Results: The silorane-based resin composite showed the lowest filler content and light attenuation among the specimens. P90 showed the highest values in the DC and the lowest microhardness at all depth. In the polymerization shrinkage, P90 showed a significantly lower shrinkage than the rest two resin products (p < 0.05). P90 showed a significantly lower refractive index than the remaining two resin products (p < 0.05). Conclusions: DC, microhardness, polymerization rate and refractive index linearly decreased as specimen thickness linearly increased. P90 showed much less polymerization shrinkage compared to other specimens. P90, even though achieved the highest DC, showed the lowest microhardness and refractive index.

• 한국식품영양과학회지
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• 제32권1호
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• pp.109-114
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• 2003

포도종실 에탄올 추출물의 각 검정 균주에 대한 생육 억제효과를 페이퍼디스크법 및 액체배양법에 의해 조사한 결과, B. subtilis ATCC 6538 혹은 S. aureus. ATCC 6538에 대하여는 농도 의존적인 증식억제 효과를 나타냈으며 P. aeruginosa IFO 3080 및 Sal. enteritidis. IFO3313에 대해서는 제한적인 증식억제 효과를 나타내기도 하였으나 E. coli ATCC 25922 에 대해서는 뚜렷한 항균 효과를 확인하기 어려웠다. 또한 포도종실 에탄을 추출물의 순차 용매 분획물 중에서 에틸아세테이트 분획과 부탄올 분획물만이 각각 35.7 mg/g과 20.2 mg/g의 카테킨을 함유하고 있었는데 에틸아세테이트 분획에 비하여 부탄을 분획물이 각 검정 균주에 대해 뚜렷한 항균활성 을 나타내었다. 부탄올 분획물은 에틸아세테이트 분획물에 비하여 카테킨의 절대 함량은 적었지만 Cl8 카트리지로 소분획하였을 때 고분자체 중심의 폴리페놀 화합물로 구성되어 있음을 알 수 있었다. 따라서 포도종실 에탄올 추출물 의 항균 활성은 카테킨과 같은 플라반-3-올 화합물의 절대 함량과 더불어 플라반-3-올 화합물의 중합도가 관계하는 것으로 예측되었다.

• 한국식품과학회지
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• 제20권2호
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• pp.205-212
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• 1988

마늘의 영하온도에서 저장시 나타나는 내한성(耐寒性)의 원인규명을 위하여 인편의 성분조성이 빙점 강하에 미치는 영향에 대하여 시험하였다. 생체(生體)마늘의 성분조성의 특징은 가용성고형분이 $40^{\circ}$ Brix(건물기준액 90%)로 일반과채류의 $10^{\circ}$ Brix에 비(比)하여 월등히 높았으며 그 구성은 총 90%중 당류가 70% 단백질이 20%였다 그리고 불용성 고형분 10%의 조성은 회분 3% 조섬유 3%였고 그외 지방, 탄수화물 및 단백질을 합(合)하여 4%정도로 되어 있었다. 마늘 성분중 당류는 fructosan이 주종(主種)이었으며 이들은 $1{\sim}29$ 중합도(Polymerization degree)의 것이 혼재되어 있으며 특히 $4{\sim}5$중합도의 것이 전체 50%이상으로 가장 많았다. 마늘의 내한성 지표인 빙점은 수용성고형분 농도가 높을수록 낮았고 동일농도일 경우에는 저중합도(低重合度)의 fructosan일수록 낮았다.

• 한국잠사곤충학회지
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• 제41권3호
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• pp.185-195
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• 1999

This study was carried out to improve the skin care property of the polyester fabric by finishing with sericin. It was known that skin care function, anti-oxidation, anti-tyrosinase activity and anti-elastase activity can be achieved from sericin finish. But, the moisture regain of the finished fabric was measured simply, because the major cause of the discomfort from polyester fabric has been anounced to be wetness. The effects of various treatment conditions on the properties of the finished fabric were measured, and obtained results were as follows: 1. The moisture regain at 40$^{\circ}C$ 90% RH were increased with the sericin uptake increasing. while it was not significant for the effects on the moisture regain depending on the treatment conditions like the degree of polymerization and treatment concentration of the binder. The moisture release of the fabric having sericin uptake 1%, 2% was faster than non treated fabric. The change of the moisture regain of the finished fabric from 40$^{\circ}C$ 90% RH to room temperature was 4∼5 times higher than that of knitted cotton fabric. 2. The frictional static charge was decreased with the degree of polymerization of the binder increasing. While the sericin uptake and treatment concentration of the binder were not significant. 3. The whiteness value of the fabric was slightly decreased by finishing with sericin and binder. In that cases, W values of the finished fabrics were above 90 while that depending on the degree of polymerization of the binder was not significant. 4. The major cause of the yellowness of the finished fabric was proved to be catalyst. The yellowness of the finished fabric with sulfur containing catalyst was lower than that with amine group containing catalyst. 5. The effects of the treatment concentrations of the cross-linking agent, catalyst and drying time on the wash durability were not significant.

• 한국수산과학회지
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• 제32권5호
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• pp.664-668
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• 1999

생분해성이며 가식성 alginate 필름을 가공하기 위하여 추출용 액의 $Na_2CO_3$ 농도와 추출시간을 달리하여 alginate를 추출하고, 동 alginate로 제조한 alginate 필름의 수증기 투과율과 장력성의 변화를 측정하였다. 추출용액중의 $Na_2CO_3$ 농도의 증가 및 추출시간의 연장과 더불어 alginate의 점도와 중합도는 감소하였다. 저점도 alginate로 만든 alginate 필름은 높은 수증기투과율을 보였다. 가소제로서 사용된 sorbitol과 polyethylene glycol 첨가는 필름의 수증기투과율과 인장강도를 현저히 낮추는 효과를 보였다. Alginate의 추출시간은 alginate필름의 수중기투과율과 신장성에 미치는 영향이 적었으나 alginate 중합도는 인장강도에 직접적으로 영향을 미쳤다.

• 대한치과보철학회지
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• 제31권4호
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• pp.506-514
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• 1993

The purpose of this study was to evaluate the effect of porcelain laminate thickness on polymerization of resin cement. G-Cera resin bonding system(G-C int., Japan) was used in this study and Heliolux II (Vivadent, Austria) was used for polymerization of resin cement. The thickness of porcelain laminates used in this study were 0.5mm, 1.0mm and 1.5mm and the degree of polymerization of resin cement was measured by microhardness theater(Matsuzawa, Model MXT-70, Japan). The obtained results were as follows : 1. The surface hardness of resin cements increaing the thickness of poreclain laminate was decreased. 2. The surface hardness of resin cements increasing the curing time was decreased.

• 한국인쇄학회지
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• 제20권1호
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• pp.65-78
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• 2002

The suspension polymerization of styrene was carried out to obtain the narrow-size distribution of particle by using poly(vinyl alcohol) (PVA) as suspension stabilizer according to the degree of hydrolysis and the molecular weight. The stabilizing properties of suspension are also dependent on the interfacial tension of aqueous solution when PVA is added. When the polymerization process was carried out with low hydrolyzed PVA, it gave single, well-defined particles, while high hydrolyzed PVA gave clusters. The size of particle produced in this study ranged between 5${\mu}{\textrm}{m}$ and 10${\mu}{\textrm}{m}$. The suspending agent, PVA, influences on the drop size and drop stability, When the molecular weight of PVA is increased, the drop size decreases and the drops become more stable toward coalescence. An increase in the PVA concentration decreases the mean drop size and narrows the drop size distribution.