• 한국추진공학회지
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• 제18권5호
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• pp.35-42
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• 2014

본 연구에서는 시차주사열량계시험, 반응열시험, 접착전단시험을 통해 자가치료제의 열분석 특성과 접착 특성을 평가하였다. 자가치료제는 DCPD와 ENB의 혼합비에 따라 D1E0, D3E1, D1E1, D1E3, D0E1을 고려하였다. 촉매는 Grubbs' catalyst를 자가치료제의 종류에 따라 0.1 wt%에서 1.5 wt%까지 적용하였다. DCPD의 경우는 촉매 양이 많을수록 중합반응이 빠르고 안정화된 접착강도가 높아지지만 많은 양의 촉매가 요구된다. ENB의 경우 촉매와의 반응성이 우수하여 적은 양의 촉매로도 빠른 중합반응을 얻을 수 있지만 반응열이 높게 나타난다. DCPD와 ENB의 혼합비를 변화시키면 자가치료제의 열분석 특성 및 접착 특성을 조절할 수 있으며 본 연구에서 고려한 자가치료제 중 D3E1가 최대접착강도, 최대접착강도에 도달하는 시간, 안정화된 접착강도, 반응열 측면에서 자가치료제로 가장 유리함을 알 수 있다.

• Restorative Dentistry and Endodontics
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• 제32권1호
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• pp.9-18
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• 2007

이 연구의 목적은 와동벽에서 다른 위치에서의 상아질 접착제의 두께를 평가하고, 이런 다양한 접착제의 두께와 미세 인장 강도 사이의 관계를 평가하기 위한 것이다. 여섯 개의 인간 대구치에 모든 상아질 면이 노출되도록 I급 와동을 형성하였다 3개의 치아는 filled adhesive ($Clearfil^{TM}$ SE bond)를 와동 내에 도포하였고, 다른 3개의 치아는 unfilled adhesives ($Scotchbond^{TM}$ Multi Purpose)를 도포하였다. 형광 현미경을 이용하여 접착층의 형태와 두께를 관찰하였다. 접착제의 두께는 수직 와동벽을 따라 와동 변연, 와동벽 1/2, 와동 내각의 세 지점에서 측정되었다. $Scotchbond^{TM}$ Multi Purpose와 $Clearfil^{TM}$ SE bond가 와동 변연과 와동벽 1/2, 와동 내각에서의 접착제의 두께를 재현하여 미세 인장 결합 강도를 측정하였다. 이 실험의 결과에서 두 가지 상아질 접착제 모두에서 와동 내각에서의 접착제의 두께가 와동 변연과 와동벽 1/2위치에서의 두께보다 두꺼웠으며, 와동 내각의 두꺼운 접착제의 미세 인장 결합 강도는 와동 변연과 와동벽 1/2에서의 얇은 접착제 두께의 미세 인장 결합 강도보다 유의성 있게 높게 나타났다.

• Journal of the Korean Wood Science and Technology
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• 제16권3호
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• pp.5-16
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• 1988

This experiment was executed to investigate the effect of activation of veneer surface by oxidizing agents, hydrogen peroxide and nitric acid, on bonding characteristics of Malas(Homalium foetidum Benth) plywood, in which the effects of these oxidizing agents amount, pretreatment time, and pressing time and temperatue on shear strength of the plywood were examined and discussed. In this research the activation of veneer surface by oxidants was effective in raising shear strength but the difference in shear strength was not observed between hydrogen peroxide and nitric acid treatment. Hydrogen peroxide treatment, however, seemed to be more profitable to industrial application because of its lower concentration and easier handling than nitric acid. The bonding method by lignin-phenol adhesive through surface activation revealed inferior shear strength to phenol- and urea-formaldehyde adhesive but superior water resistance to urea-formaldehyde adhesive and this bonding method, in addition, have the advantage of lower cost compared with phenol-formaldehyde adhesive, Therefore, this bonding method by lignin-phenol adhesive through surface activation seemed to economical in manufacturing of water-resistant wood panel materials in future.

• 대한치과교정학회지
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• 제48권3호
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• pp.163-171
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• 2018

Objective: The aim of this study was to evaluate the mechanical and biological properties of orthodontic bonding agents containing silver- or zinc-doped bioactive glass (BAG) and determine the antibacterial and remineralization effects of these agents. Methods: BAG was synthesized using the alkali-mediated solgel method. Orthodontic bonding agents containing BAG were prepared by mixing BAG with flowable resin. $Transbond^{TM}$ XT (TXT) and $Charmfil^{TM}$ Flow (CF) were used as controls. Ion release, cytotoxicity, antibacterial properties, the shear bond strength, and the adhesive remnant index were evaluated. To assess the remineralization properties of BAG, micro-computed tomography was performed after pH cycling. Results: The BAG-containing bonding agents showed no noticeable cytotoxicity and suppressed bacterial growth. When these bonding agents were used, demineralization after pH cycling began approximately 200 to $300{\mu}m$ away from the bracket. On the other hand, when CF and TXT were used, all surfaces that were not covered by the adhesive were demineralized after pH cycling. Conclusions: Our findings suggest that orthodontic bonding agents containing silver- or zinc-doped BAG have stronger antibacterial and remineralization effects compared with conventional orthodontic adhesives; thus, they are suitable for use in orthodontic practice.

• 접착 및 계면
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• 제4권3호
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• pp.9-13
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• 2003

본 연구에서는 점착제의 유지력 개선과 pH 조절을 위해 각각 첨가해 주는 가교제와 pH 조절제의 종류 및 첨가량이 수용성 아크릴 점착제의 점착 물성 및 수용성에 미치는 효과를 알아보기 위하여 중합된 점착 시료에 여러 가지의 가교제와 pH 조절를 첨가해 준 후 초기점착력, 유지력 및 점착력 등의 점착 물성과 수용성을 측정하였다. 가교제를 0.2 wt% 미만 첨가해 주었을 때, 초기 점착력은 감소하였고 유지력과 점착력은 증가하였다. 그러나 0.2 wt% 이상 첨가해 주었을 때는 초기 점착력은 증가하였지만 유지력과 점착력은 감소하는 결과를 보였다. 또한 pH 조절제를 첨가해 주었을 때 pH 조절제의 농도가 증가함에 따라 초기점착력과 수용성은 감소하였고 점착력과 유지력은 증가하였으며, LiOH, KOH, NaOH 순으로 점착 물성과 수용성에 미치는 영향이 큰 것으로 나타났다.

• Restorative Dentistry and Endodontics
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• 제12권2호
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• pp.55-63
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• 1987

The purpose of this study is to evaluate the effect of dentin bonding agents on marginal leakage. V-shaped cavities were prepared on the faciocervical area of 140 extracted human teeth. In Groups of twenty cavities, they were restored as follow: Group 1 with enamel bonding resin and Silux, Group 2 Scotchbond and Silux, Group 3 enamel bonding resin and Heliomolar, Group 4 Dentin Adhesit and Heliomolar, Group 5 enamel bonding resin and Durafill, Group 6 Dentin Adhesive and Durafill, Group 7 Chembond. All specimens were thermocycled alternatively at $4^{\circ}C$ and $60^{\circ}C$ of 2% methylene blue dye solution, and sectioned faciolingually with diamond disk under water spray. The sectioned specimens observed with stereo microscope. Following results were obtained: 1. The groups filled with Scotchbond-Silux or Dentin Adhesit-Heliomolar had appeared lesser marginal leakage compared with the groups with enamel bonding resin-Silux or enamel bonding resin-Helimolar. 2. The group filled with Dentin Adhesive-Durafill did not show the reduction of the marginal leakage compared with the group with enamel bonding resin-Durafill. 3. There was significant difference among the four dentin bonding agents. Scotchbond showed the greatest marginal sealing ability, and Dentin Adhesit was the next. The marginal sealing ability of Dentin Adhesive was the worst.

• 보존과학회지
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• 제35권4호
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• pp.269-277
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• 2019

Seaweed extracts, namely carrageenan obtained from Grateloupia elliptica and algin obtained from Laminaria, were employed as adhesive agents to synthesize solid adhesives for paper. Carrageenan from Grateloupia elliptica with the highest adhesive strength and lgin from Laminaria with the highest compressive strength was selected. The selected carrageenan and algin were mixed in a ratio of 7:3, and the mixture was employed as an adhesive agent. At a high temperature, sodium stearate(used as a solidifying material) oxidized the seaweed extracts. Consequently, carrageenan and algin were added to the final manufacturing process. The adhesive strength of the final synthesized solid adhesive is found to be 3.02 MPa and the compressive strength is found to be 30.5 N. Compared to the adhesive strength (2.95 MPa) and compressive strength (30.11 N) of commercial solid adhesives, the obtained results indicate superior adhesion characteristics. Furthermore, the proposed adhesive is environment-friendly because the presence of volatile organic compounds, formaldehyde, and heavy metals(such as chromium, lead, and cadmium) were not detected. Moreover, when used, the flatness of paper was twice that of commercial solid paper adhesives. Hence, the proposed adhesive can provide excellent adhesion, stability, and usability.

• 한국인쇄학회지
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• 제28권2호
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• pp.1-11
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• 2010

The physicochemical characteristics, adhesion power, and conservation of imported tapes repairing documents that consisted of adhesive, carrier, and masking were investigated. Materials related to pressure sensitive adhesive produced in domestic companies were examined also. And then, the performance evaluation of prototype manufactured in our laboratory was undertaken. Both the pressure sensitive tapes were compared. The polyacrylate of adhesive agents such as polyacrylate, starch, Glue, and PVA of imported tapes was best. The adhesion strength, power, reversibility, and stability (deterioration) of imported tapes were analyzed. By comparing results of imported tapes, two adhesive agents were selected finally. The carriers of imported tapes are made of one of papers, cotton sheets, and felts. Major carrier material was a paper. The jutes, conifers, and hardwoods were main ingredient of papers. The durability of Hangi($18{\pm}2g/m^2$) was one and half times superior to imported one.

• 접착 및 계면
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• 제17권2호
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• pp.56-61
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• 2016

본 연구에서는 아크릴 접착제의 물성에 대한 주 모노머의 영향을 비교하기 위하여 2-ethylhexyl acrylate 대신에 butyl acrylate를 사용하여 acrylic acid와 2-hydroxyethyl methacrylate의 공중합체를 합성하고 2종의 경화제를 이용하여 접착 물성을 연구하였다. 선형의 측쇄사슬을 가진 butyl acrylate계 점착제는 가지형태의 측쇄를 가진 2-ethylhexyl acrylate계 접착제에 비해 낮은 접착특성을 보였다. 경화제의 경우 가교점이 많고 가교반응을 통해 유연한 ether나 ester그룹을 생성하는 epoxy형 경화제에서 우수한 물성을 보였고 관능기인 산의 농도가 높을수록 접착특성이 향상되는 것을 관찰하였다.

• Clinics in Shoulder and Elbow
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• 제20권1호
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• pp.3-9
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• 2017

Background: Many hyaluronic acid (HA)-based anti-adhesive agents have been commercialized for clinical use in the pharmaceutical market. But their efficacy in arthroscopic rotator cuff repairs remains elusive. To determine their efficacy, we performed a comparative analysis of the effects of two hyaluronate/carboxymethylcellulose (CMC)-based anti-adhesive agents, Protescal and Guardix. Methods: We recruited a total of 256 patients who had received an arthroscopic rotator cuff repair at our hospital between January 2014 and March 2015. Among them, 96 patients fulfilled the study's selection criteria and were enrolled as the final population sample. Thirty patients who had received a postoperative injection of Protescal were allocated into Group A. Another 30 patients who had received a postoperative injection of Guardix were allocated into Group B. As controls, 36 patients who did not receive any injection were allocated into Group C. The patients included in this study were aged between 19 and 75 years. For the clinical assessment, we measured the following clinical parameters-the visual analogue scale for pain (PVAS), the American Shoulder and Elbow Surgeons (ASES) score, and the constant score, as well as passive range of motions (ROMs)-at three time-points (preoperatively, 2-month postoperatively, and 6-month postoperatively). Results: We found that Group A compared to Group B tended to show a swifter recovery in passive anterior elevation and in internal rotation by the 2-month postoperative follow-up, but the differences were not statistically significant. Conclusions: We found that the effects of HA/CMC-based injections were minimal after arthroscopic rotator cuff repairs.