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  • 제목/요약/키워드: Bonding Adhesives

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Effect of adhesive application method on repair bond strength of composite

  • Hee Kyeong Oh;Dong Hoon Shin
    • Restorative Dentistry and Endodontics
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    • v.46 no.3
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    • pp.32.1-32.10
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    • 2021
  • Objectives: This study aimed to evaluate the effect of the application method of universal adhesives on the shear bond strength (SBS) of repaired composites, applied with different thicknesses. Materials and Methods: The 84 specimens (Filtek Z350 XT) were prepared, stored in distilled water for a week and thermocycled (5,000 cycles, 5℃ to 55℃). They were roughened using 400-grit sandpapers and etched with phosphoric acid. Then, specimens were equally divided into 2 groups; Single Bond Universal (SU) and Prime&Bond Universal (PB). Each group was subdivided into 3 subgroups according to application methods (n = 14); UC: 1 coat + uncuring, 1C: 1 coat + curing, 3C: 3 coats + curing. After storage of the repaired composite for 24 hours, specimens were subjected to the SBS test and the data were statistically analyzed by 2-way analysis of variance and independent t-tests. Specimens were examined with a stereomicroscope to analyze fracture mode and a scanning electron microscope to observe the interface. Results: Adhesive material was a significant factor (p = 0.001). Bond strengths with SU were higher than PB. The highest strength was obtained from the 1C group with SU. Bonding in multiple layers increased adhesive thicknesses, but there was no significant difference in SBS values (p = 0.255). Failure mode was predominantly cohesive in old composites. Conclusions: The application of an adequate bonding system plays an important role in repairing composite resin. SU showed higher SBS than PB and the additional layers increased the adhesive thickness without affecting SBS.

THE COMPARATIVE STUDY FOR THE SHEAR BOND STRENGTH OF DENTAL ADHESIVES CURED WITH VARIOUS LIGHT SOURCES (다양한 광원으로 중합한 치과용 접착제의 전단강도에 관한 비교 연구)

  • Choi, Nam-Ki;Cho, Seong-Hoon;Kim, Seon-Mi
    • Journal of the korean academy of Pediatric Dentistry
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    • v.38 no.1
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    • pp.33-41
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    • 2011
  • The objective of this study was to compare the shear bond strengths of five dentin adhesive systems cured with three different light curing sources. Seventy five noncarious permanent teeth were collected and stored in an 0.1% thymol solution at room temperature after extraction. The tested adhesives were: Adper Scotchbond Multi-purpose Plus Adhesive (SM) Adper Single bond 2 (SB), Clearfil SE Bond (SE), Adper Prompt L-Pop (PL), G-Bond (GB). And three light curing unit systems were used: Elipar Free light 2(LED), OptiLux 501 (Halogen), Flipo (PAC). For the shear bonding test, the labial and lingual surfaces of permanent teeth were used. To obtain a flat dentin surface, the labial and lingual surfaces of the teeth were sanded on SiO2 with number 600 grit and then divided into 15 groups of 10 surfaces each. All samples were theromocycled in water 5C and 55C for 1000 cycles. The results were as follows: 1. When cured with Freelight 2, the shear bond strength of SM was significantly higher than that of PL, GB (p<0.05), whereas no significant difference was found among those of any other bonding agents. 2. When cured with Optilux 501, the shear bond strength of SM was significantly higher than those of any other bonding agents (p<0.05), whereas no singnificant difference was found among those of andy other bonding agents. 3. When cured with Flipo, the shear bond strength of SM was significantly higher than those of SB, SE, GB (p<0.05), whereas no significant differences was found among those of any other bonding agents. 4. For comparison according to three different light cure unit system, except SB and GB, each three dentin bonding agents showed no significant difference. For SB, only Freelight 2 was significantly higher than the others, with no significant difference between Optilux 501 and Flip. For GB, Statistically significant difference was found only between Freelight and Flipo.

THE BONDING DURABILITY OF TOTAL ETCHING ADHESIVES ON DENTIN (산부식형 상아질 접착제의 접착 내구성에 관한 연구)

  • Jung, Mi-Ra;Choi, Gi-Woon;Park, Sang-Hyuk;Park, Sang-Jin
    • Restorative Dentistry and Endodontics
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    • v.32 no.4
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    • pp.365-376
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    • 2007
  • The purpose of this study was to evaluate the effect of different etching times on microtensile bond strength (μTBS) to dentin both initial and after thermocycling with 3 different types of total-etching adhesives. Fifty four teeth were divided into 18 groups by etching times (5, 15, 25 sec), adhesives types (Scotchbond Multipurpose (SM), Single Bond (SB), One-Step (OS)) and number of thermocycling (0, 2,000 cycles). Flat dentin surfaces were prepared on mid-coronal dentin of extracted third molars. After exposed fresh dentin surfaces were polished with 600-grit SiC papers, each specimen was acid-etched with 35% phosphoric acid (5, 15, 25 sec) and bonded with 3 different types of total etching adhesives respectively. Then, hybrid composite Z-250 was built up. Half of them were not thermocycled (control group) and the ethers were subjected to 2,000 thermocycle (experimental group). They were sectioned occluso-gingivally into 1.0×1.0mm2 composite-dentin beams and tested with universal testing machine at a crosshead speed of 1.0 mm/min. Within limited data of this study, the results were as follows 1. There was no statistically significant difference in μTBS between the thermocycled and non-thermocycled groups, except for both SM and SB etched for 25 sec. 2. In thermocycled SM and SB groups, bond strength decreased by extended etching time. In total etching systems, adhesive durability for dentin could be affected by type of solvents in adhesive and etching time. Especially, extended etching time may cause deteriorate effects on bond strength when ethanol-based adhesive was used.

Effects of Blending Fatty Acid-Glycerol-pMDI with Urea-Formaldehyde Resin Adhesives to Their Adhesion for the Use of Soybean Oil (콩기름 이용을 위한 지방산-글리세롤-pMDI와 요소수지 혼용 접착제가 접착성능에 미치는 영향-)

  • You, Young-Sam;Choi, Jin-Lim;Seo, Jun-Won;Park, Heon
    • Journal of the Korean Wood Science and Technology
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    • v.34 no.4
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    • pp.31-36
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    • 2006
  • This study was conducted to improve the bond strength of plywood bonded with F/U molar ratio urea-formaldehyde (UF) resins modified with the selected FGMDI prepolymer contents for various purposes. The amount of FGMDI was mixed with liquid UF resin at 0 wt% (as control), 2 wt%, 5 wt%, 10 wt%, 25 wt%, and 50 wt% based on the resin solids. As results, in bonding strength, plywood with F/U molar ratio of 1.4 showed the highest value in Type 2 test and all molar ratio UF resins modified with over 25 wt% of the FGMDI showed more than 11kgf/cm2, which was satisfied the minimum requirement of KS standard, 7.5kgf/cm2, after Type1.5 testing. As F/U molar ratio was increased and the FGMDI addition in the UF resin was increased, average reduction rate of Type 1.5 bonding strength compared with Type 2 was significantly decreased.

Physicochemical Characteristics Study on Wheat Starch Adhesive - Based on Wheat Starch Adhesive fermenting period less than two years- (소맥전분 풀의 이화학적 특성 연구 - 수침기간이 2년 이하인 풀을 중심으로-)

  • Chung, Yong-Jae;Kim, Min-Jeong;Nam, Seo-Jin;Jeong, Seon-Hye
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.44 no.2
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    • pp.35-41
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    • 2012
  • In this study, wheat starch adhesive was investigated the shape and structure of starch, the difference in characteristics such as chemical composition according to the fermenting period of 2 years or less. The fermenting period of wheat starch adhesive is 1 month, 2months, 4 months,6 months, 1 year, 2years old. The wheat starch adhesives were investigated total sugar contents, protein contents, properties of gelatinization, pH, the bonding strength and also observed the surface of starch,. As a result, the longer the fermenting period, the increasing in total sugar contents and decreasing in protein contents. The particle shape and surface were similar regardless of the period. In addition, properties of gelatinization according to the fermenting period also could not see the difference. In pH of the adhesive, the longer the fermenting period, the near to neutral. The adhesive was high bonding strength in 4 months, but appeared a tendency to decrease from 6 months. The damage assessment through the UV degradation in regard to the papers applied the adhesive was accomplished. Color difference was no change except 1 month. The 4 months and 6 months' pH was each 5.0, 5.2. But it was near to neutral that the 12 months and 24 months' pH was each 5.7, 5.9.

The Effect of the Core-shell Structured Meta-aramid/Epoxy Nanofiber Mats on Interfacial Bonding Strength with an Epoxy Adhesive in Cryogenic Environments (극저온 환경에서 에폭시 접착제의 물성 향상을 위한 나노 보강재의 표면 개질에 관한 연구)

  • Oh, Hyun Ju;Kim, Seong Su
    • Composites Research
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    • v.26 no.2
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    • pp.129-134
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    • 2013
  • The strength of adhesive joints employed in composite structures under cryogenic environments, such as LNG tanks, is affected by thermal residual stress generated from the large temperature difference between the bonding process and the operating temperature. Aramid fibers are noted for their low coefficient of thermal expansion (CTE) and have been used to control the CTE of thermosetting resins. However, aramid composites exhibit poor adhesion between the fibers and the resin because the aramid fibers are chemically inert and contain insufficient functional groups. In this work, electrospun meta-aramid nanofiber-reinforced epoxy adhesive was fabricated to improve the interfacial bonding between the adhesive and the fibers under cryogenic temperatures. The CTE of the nanofiber-reinforced adhesives were measured, and the effect on the adhesion strength was investigated at single-lap joints under cryogenic temperatures. The fracture toughness of the adhesive joints was measured using a Double Cantilever Beam (DCB) test.

Investigation of the Bonding Stress of the 2nd Barrier for LNG Carrier Cargo Containment System Considering Various Working Conditions (다양한 작업 조건을 고려한 LNG 운반선 화물창 2차 방벽의 극저온 접착강도 분석)

  • Jeong-Hyeon Kim;Hee-Tae Kim;Byeong-Kwan Hwang;Seul-Kee Kim;Tae-Wook Kim;Doo-Hwan Park;Jae-Myung Lee
    • Journal of the Korean Society of Industry Convergence
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    • v.26 no.3
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    • pp.499-507
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    • 2023
  • The core of the liquefied natural gas (LNG) carrier cargo containment system (CCS) is to store and transport LNG safely under temperatures below -163 degrees Celsius. The secondary barrier of the LNG CCS is adopted to prevent LNG leakage from CCS to the ship's hull structure. Recently, as the size of the LNG CCS increases, various studies have been conducted on the applied temperature and load ranges. The present study investigates the working condition-dependent bonding strength of the PU15 adhesives of the secondary barrier. In addition, the mechanical performance is analyzed at a cryogenic temperature of -170 degrees Celsius, and the failure surface and failure mode are investigated depending on the working condition of the bonded process. Even though the RSB and FSB-based fracture mode was confirmed, the results showed that all the tested scenarios satisfied the minimum requirement of the regulation.

Bonding effects of cleaning protocols and time-point of acid etching on dentin impregnated with endodontic sealer

  • Tatiane Miranda Manzoli;Joissi Ferrari Zaniboni;Joao Felipe Besegato;Flavia Angelica Guiotti;Andrea Abi Rached Dantas;Milton Carlos Kuga
    • Restorative Dentistry and Endodontics
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    • v.47 no.2
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    • pp.21.1-21.11
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    • 2022
  • Objectives: This study aimed to investigate the bonding effects of cleaning protocols on dentin impregnated with endodontic sealer residues using ethanol (E) or xylol (X). The effects of dentin acid etching immediately (I) or 7 days (P) after cleaning were also evaluated. For bonding to dentin, universal adhesive (Scotchbond Universal; 3M ESPE) was used. The persistence of sealer residues, hybrid layer formation and microshear bond strength were the performed analysis. Materials and Methods: One hundred and twenty bovine dentin specimens were allocated into 4 groups (n = 10): G1 (E+I); G2 (X+I); G3 (E+P); and G4 (X+P). The persistence of sealer residues was evaluated by SEM. Confocal laser scanning microscopy images were taken to measure the formed hybrid layer using the Image J program. For microshear bond strength, 4 resin composite cylinders were placed over the dentin after the cleaning protocols. ANOVA followed by Tukey test and Kruskal-Wallis followed by Dunn test were used for parametric and non-parametric data, respectively (α = 5%). Results: G2 and G4 groups showed a lower persistence of residues (p < 0.05) and thicker hybrid layer than the other groups (p < 0.05). No bond strength differences among all groups were observed (p > 0.05). Conclusions: Dentin cleaning using xylol, regardless of the time-point of acid etching, provided lower persistence of residues over the surface and thicker hybrid layer. However, the bond strength of the universal adhesive system in etch-and-rinse strategy was not influenced by the cleaning protocols or time-point of acid etching.

Effect of Veneer Moisture Content on Bonding Strength of Plywood Bonded with Fatty Acid-Glycerol-pMDI Adhesive(I) - Dry Bonding Strength - (단판 함수율이 지방산·글리세롤·pMDI의 접착력에 미치는 영향(I) - 상태접착력 -)

  • Choi, Jin-Lim;Lee, Tack-Jun;Park, Heon
    • Journal of the Korean Wood Science and Technology
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    • v.34 no.6
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    • pp.29-35
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    • 2006
  • This stud y was conducted to investigate the bonding strength of plywood bonded with fatty acid-glycerol-pMDI adhesives with equivalent ratios of 1:1:2, 1:1:3, 1:1:4, 1:1:5, and 1:1:6. With veneer moisture contents of 0%, 3%, 5%, 8% and 15%, the bonding strengths exceeded the requirement of Korean plywood standard of 7.0kgf/cm2 with values of 13.7kgf/cm2, 11.6kgf/cm2, 11.2kgf/cm2, 9.8kgf/cm2, and 7.4kgf/cm2, respectively at fatty acid-glycerol-pMDI ratio of 1:1:2. With veneer moisture content of 30%, the bonding strengths exceeded th e requirement of Korean plywood standard of 7.0kgf/cm2, when fatty acid-glycerol-pMDI ratios were 1:6. Finally for satisfying the Korean plywood standard, the ratio of MDI in fatty acid-glycerol-pMDI should be increased with increasing of veneer moisture content.

Photovoltaic performance evaluation of the bonded single crystalline silicon solar cell on composite specimens under mechanical loading (기계적 하중 하에서 복합재료 시험편에 접착된 단결정 실리콘태양전지의 성능평가)

  • Kim, Jong-Cheon;Choi, Ik-Hyeon;Kim, Dae-Hyun;Jeong, Seong-Kyun
    • Composites Research
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    • v.24 no.6
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    • pp.56-63
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    • 2011
  • The objective of this study is to investigate appropriate bonding methods of solar cells in order to apply solar cells, which have been receiving particular attention as a renewable energy due to fossil energy depletion and environment issues, to composite structures. Back-contact solar cells with approximately 24.2% energy conversion efficiency were used in this study. Since silicon-based solar cells are mechanically fragile, the secondary-bonding methods using adhesive were examined in this study. The experiment was conducted with three kinds of bonding materials such as EVA film, Resin film and elastic adhesive. The performance of solar cells for three types of adhesives under mechanical loading on test specimens is conducted. In addition, the measuring equipment was designed to evaluate the performance of the solar cells under mechanical loading in real time and the fracture characteristics depending on bonding materials were evaluated. The reason decreasing solar cells efficiency were analyzed and considered by Fractography. The results show that the solar cell performance is largely affected by bonding techniques. Moreover, the bonding method using elastic adhesive shows best solar cell efficiency.