• 공업화학
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• 제3권4호
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• pp.627-638
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• 1992

분자량과 관능기수가 각각 다른 4가지의 polypropylene glycol(PPG)과 toluene-2, 4-diisocyanate(2, 4-TDI)를 이용하여 polyurethane prepolymer(NCO terminated)를 합성한 후 NCO기 말단에 2-hydroxyethyl methacrylate(2-HEMA)를 반응시켜 PPG계 polyurethane methacrylates 수지를, PPG대신에 bisphenol A(BPA)를 이용하여 BPA계 polyurethane dimethacrylate 수지를 합성하였다. 합성된 PPG계 polyurethane dimethacrylate 수지에 반응성희석제인 triethylene glycol dimethacrylate(TEGDMA), 중합개시제인 cumene hydroperoxide(CHP) 중합금지제인 hydroquinone(HQ)를 첨가하였을 때, 첨가량변화에 따른 토오크강도의 변화를 고찰하였고, BPA계 polyurethane dimethacrylate 수지와 블렌드하였을때의 조성비에 따른 토오크강도의 변화를 고찰하였다. 토오크 측정결과, TEGDMA 40wt%, cumene hydroperoxide 4wt%, hydroquinone 200 ppm이 첨가되었을 때, 가장 큰 토오크강도를 나타내었으며, PPG계와 BPA계를 블렌딩하였을 때는 PPG/BPA가 4/6일 때 가장 큰 토오크강도를 나타내었다. 반응성희석제인 triethylene glycol dimethacrylate(TEGDMA), 중합개시제인 cume hydroperoxide(CHP), 중합금지제인 hydroquinone(HQ)를 동일하게 첨가한 후, 분자량과 관능기수가 다른 PPG계 polyurethane dimethacrylate 수지들의 열경화시의 토오크강도를 측정한 결과, 관능기수가 같은 수지들(PD750, PD1000, PD2000)의 경우에는 분자량이 적은 수지(PD750)일수록 큰 토오크강도를 나타내었고, 관능기수가 많을수록(PT 700) 큰 토오크강도를 나타내었다. 개시제만을 첨가한 후, 열경화를 통해서 얻어진 PPG계 수지들의 겔들을 DSC분석을 통해서 Tg변화를 측정하여 본 결과, 경화시 분자량이 가장 적고, 관능기수가 가장 많은 PT 700이 가장 큰 폭의 Tg증가를 나타내었으며, 분자량이 가장 큰 수지인 PD 2000이 가장 적은 폭의 Tg증가를 나타내었다. 그리고, Tg를 통해서 가교점간 분자량 Mc를 측정한 결과, 가장 큰 폭의 Tg를 보인 PT 700가 가장 적은 Mc를 가지고 있었다. 따라서, PT 700이 경화시 가장 조밀한 망목구조를 형성한다는 것을 확인할 수 있었다.

• Macromolecular Research
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• 제16권5호
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• pp.424-428
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• 2008

We prepared an ionic gel polymer electrolyte for dye-sensitized solar cells (DSSCs) without leakage problem. Triiodide compound (BTDI) was synthesized by the reaction of benzene tricarbonyl trichloride with diethylene glycol monotosylate and subsequent substitution of tosylate by iodide using NaI. Bisimidazole was prepared by the reaction of imidazole with the triethylene glycol ditosylate under strongly basic condition provided by NaH. BTDI and bisimidazole dissolved in an ionic liquid were injected into the cells and permeated into the $TiO_2$ nanopores. In situ crosslinking was then carried out by heating to form a network structure of poly(imidazolium iodide), thereby converting the ionic liquid electrolytes to a gel or a quasi-solid state. A monomer (BTDI and bisimidazole) concentration in the electrolytes of as low as 30 wt% was sufficient to form a stable gel type electrolyte. The DSSCs based on the gel polymer electrolytes showed a power conversion efficiency of as high as 1.15% with a short circuit current density of $5.69\;mAcm^{-2}$, an open circuit voltage of 0.525 V, and a fill factor of 0.43.

• Bulletin of the Korean Chemical Society
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• 제21권11호
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• pp.1115-1118
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• 2000

Specimens were cured by using a 1 mm (thickness) ${\times}$5 mm (diameter) teflon mold, and were immersed in artificial saliva and in 75% ethanol for 1, 7, 14, 21 and 28 days in order to quantify and to identify toxic components and to determine any degra dation byproducts of Bis-GMA that might be released from five commercially available resin-based dental sealants. In artificial saliva, the only released component was triethylene glycol dimethacylate (TEGDMA). In 75% ethanol, TEGDMA, 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy) phenyl]propane (Bis-GMA) and urethane dimethacrylate (UDMA) were released highly at the initial stage, indicating that the amount of component released is not linearly correlated with the immersion time. The amount of released TEGDMA was found to be much higher in 75% ethanol than in artificial saliva. Importantly, bisphenol-A (BPA) was detected from all the uncured sealants tested, suggesting that all the sealants tested contain BPA as a contaminant.

• 통합자연과학논문집
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• 제12권2호
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• pp.29-34
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• 2019

In dental resin cement studies, viscosity is also an important factor in the adhesion of tooth defects and implants. This study used BisGMA and HPMA as the main ingredients, triethylene glycol dimethacrylate (TEGDMA) as a diluent, and benzoyl peroxide (BPO) as a photoinitiator. The physical properties of graphene oxide used as an additive for functionality were evaluated, and its use as a dental resin cement material was investigated.The rupture strength has the tendency to increase along with the increase of the ratio of graphene oxide that was added, which seemed to reflect the effect of the high strength property of graphene oxide. The flexural strength also has the tendency to increase when about 0.5% of graphene oxide was added the same as the increase of rupture strength.When graphene oxide was added, according to viscosity use, the utilization as high-quality dental resin cements will increase.

• 치위생과학회지
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• 제18권6호
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• pp.367-373
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• 2018

시판 중인 어린이 음료가 레진계 치면열구전색제에 미치는 물리 화학적 영향을 알아보기 위해 판매량이 높은 3종의 어린이 음료와 대조군으로 생수를 선정하였다. 제조사의 지시에 따라 레진 시편을 제작하여 시편의 초기 거칠기 값(Ra)를 측정하였고, 각 음료의 pH를 측정한 후, 레진 시편을 각각의 음료에 침지시켜 $37^{\circ}C$ 배양기에서 72시간 보관하였다. 72시간 후 레진 시편의 표면 거칠기를 측정하였고 시편 표면의 형태변화 관찰을 위해 주사전자현미경으로 관찰하였다. 레진 시편에서 용출된 단량체의 종류 및 용출량은 HPLC를 이용하여 비교 분석하였다. 생수를 제외한 모든 실험음료에 구연산이 첨가되어 있었고 어린이 음료의 평균 pH는 $3.25{\pm}0.17$로 '아이키커'에서 $3.03{\pm}0.01$로 가장 낮았고 '뽀로로'에서 $3.47{\pm}0.02$로 가장 높았다. 어린이 음료에 침지 후 시간 경과에 따른 표면 거칠기가 증가하였고 레진 시편의 표면에 기질의 탈락을 관찰하였다. 모든 실험음료에서 bis-GMA는 유출되지 않았으나 생수를 제외한 어린이 음료에서는 TEGDMA가 유출되었다. 이상의 결과 어린이 음료는 치면열구전색제의 열화와 단량체의 유리를 촉진할 수 있으며 유리된 단량체는 성장 중인 어린이에게 더 큰 영향을 미칠 수 있으므로 어린이 음료를 빈번히 음용하는 것은 주의가 필요하다.

• 전기화학회지
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• 제7권4호
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• pp.189-193
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• 2004

본 연구에서는 POAGA와 TEGDMA로 구성된 반응성 단량체에서 두 단량체 및 개시제의 조성에 따른 겔폴리머전해질전지를 제조하고 전지특성을 평가하였다 POAGA계 겔폴리머전해질은 단량체의 함량이 증가함에 따라 겔화 시간은 감소하였다. POAGA계 겔폴리머전해질은 4.5V까지 전기화학적으로 안정하였으며, 상온 이온전도도는 약 $5.2\times10^{-3}Scm^{-1}$이었다. POAGA계 겔폴리머전해질을 채용한 리튬이온폴리머전지는 반응성 단량체의 함량이 $5.0wt\%$ 및 $7.0wt\%$인 경우에 비하여 $3.0wt\%$인 경우가 고율, 저온 및 사이클 특성이 우수하였다 또한 개시제 함량은 $1.0\~3.0wt\%$ 범위에서는 $1.0wt\%$인 경우가 우수한 전지특성을 나타내었다.

• 대한통합의학회지
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• 제8권3호
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• pp.53-62
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• 2020

Purpose :Periodontal ligament stem cells maintain tissue homeostasis in periodontal ligament. The purpose of this study was to determine the characteristics of periodontal ligament stem cells isolated from premolar teeth and observe protective effects against oxidative damage caused by Triethylene glycol dimethacrylate (TEGDMA) following treatment with N-acetylsysteine amide (NACA) drug known as enzymatic antioxidants. Methods : Primary periodontal ligament stem cell (PDSC) culture was performed from simply extracted human premolar of orthodontic patients. The characteristics of the primary cultured PDSCs was analyzed using the FACS system. PDSCs was incubated with TEGDMA and NACA. The cell proliferation and survival was determined using WST-1 assay. Collected data were analyzed using SPSS Window 20. Results : Primary cultured PDSCs grow on the floor and develop rapidly in a cluster form from up to 14 days. The morphology of PDSCs showed the spindle-shaped cells and grew directionally. FACS analysis, In addition, positive expression of visible cells were observed in mesenchymal stem cell biomarkers. PDLSCs cell viability was significantly decreased at high concentration in both 3 and 6 hours after TEGDMA treatment. We observed a decrease in the number of cells as well as a morphological change of PDLSCs. Antioxidative effect was notable since the death of PDLSC death was significantly inhibited compared to the control group at 24 and 48 hours after NACA treatment. Conclusion : Therefore, based on the results of this study, further research should be encouraged considering the development of clinical treatment methods using various antioxidants as well as regenerative engineering techniques utilizing periodontal ligament stem cells.

• Macromolecular Research
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• 제12권3호
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• pp.303-310
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• 2004

We have prepared an aqueous dispersion of poly(aniline-dodecyl benzene sulfonic acid complex) (PANI-DC) that has an intrinsic viscosity (〔η〕) near 1.3 dL/g using aniline as a monomer, dodecyl benzene sulfonic acid(DBSA) as a dopant/emulsifier, and ammonium peroxodisulfate(APS) as an oxidant. We found that the electrical conductivity of a PANI-DC pellet was 0.7 S/cm. A waterborne-polyurethane (WBPU) dispersion, obtained from isophorone diisocyanate/polytetramethylene oxide glycol/dimethylol propionic acid/ethylene diamine/triethylene amine, was used as a matrix polymer. We prepared blend films of WBPU/PANI-DC with variable weight ratios (from 99/1 to 66/34) by solution blending/casting and investigated the effects that the PANI-DC content has on the mechanical and dynamic mechanical properties, hardness, electrical conductivity, and antistaticity of these films. The tensile strength, percentage of elongation, and hardness of WBPU/PANI-DC blend films all decreased markedly upon increasing the PANI-DC content. The antistatic half-life time ($\tau$$\sub$$\frac{1}{2}$/) of pure WBPU film was about 110 s, but we found that those of WBPU/ultrasound-treated PANI-DC blend films decreased exponentially from 1.2 s to 0.1 s to almost 0 s upon increasing the PANI-DC content from 1 wt% to 15 wt% to > 15 wt%, respectively.

• 대한치과보철학회지
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• 제41권4호
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• pp.476-492
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• 2003

Purpose : The purpose of this study was to compare HEMA and TEGDMA as diluents for the composite resin. Material and methods : Eight kinds of experimental light curable composite resins were prepared and used. Concentrations of monomer and filler were same for all experimental composites, except, the diluent's ratios to the monomer. The ratio of diluents to Bis-GMA were 15%, 20%, 25%, and 30%, and two kinds of diluents were used, so total experimental groups were eight including one control group of 25% TEGDMA. Results : Depth of cure, flexural strength, shear bond strength to bovine enamel, shear bond strength to bovine dentin, water absorption and solubility of composites in water were measured. Sample size for each groups were 10. Arithmetic means were used as each groups representative values, and regression test for two diluents and low concentrations, Duncan's multiple range test, and Two-way ANOVA test were done for kinds of diluents and its concentrations at level of 0.05. Conclusion : Following results were obtained ; 1. There were not significant differences in effects of HEMA and TEGDMA to depth of cure, flexural strength of composites and shear bond strength to bovine enamel (p>0.05). 2. Increase of the concentrations of the diluents made the depth of cure (p<0.001) and flexural strength (p<0.05) a little higher. 3. Shear bond strength to dentin was higher on HEMA containing composites than TEGDMA containing composites (p<0.001). 4. Water absorption was higher on HEMA containing composites than TEGDMA containing composites (p<0.01).

• Restorative Dentistry and Endodontics
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• 제45권3호
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• pp.32.1-32.12
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• 2020

Objectives: To evaluate the polymerization efficiency of a matrix-modified bulk-fill composite, and compare it to a conventional composite which has a similar filler system. The degree of conversion (DC%) and monomer elution were measured over different storage periods. Additionally, fillers' content was examined. Materials and Methods: Cylindrical specimens were prepared, in bulk and incrementally, from Filtek Bulk Fill (B) and Filtek Supreme XTE (S) composites using a Teflon mold, for each test (n = 6). Using attenuated total reflection method of Fourier transformation infrared spectroscopy, DC% was measured after 24 hours, 7 days, and 30 days. Using high-performance liquid chromatography, elution of hydroxyethyl methacrylate, triethylene glycol dimethacrylate, urethane dimethacrylate, and bisphenol-A glycidyl dimethacrylate was measured after 24 hours, 7 days and 30 days. Filler content was examined by scanning electron microscopy (SEM). Data were analyzed using 2-way mixed-model analysis of variance (α = 0.05). Results: There was no significant difference in DC% over different storage periods between B-bulk and S-incremental. Higher monomer elution was detected significantly from S than B. The elution quantity and rate varied significantly over storage periods and between different monomers. SEM images showed differences in fillers' sizes and agglomeration between both materials. Conclusions: Matrix-modified bulk-fill composites could be packed and cured in bulk with polymerization efficiency similar to conventional composites.