• Restorative Dentistry and Endodontics
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• 제24권2호
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• pp.381-391
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• 1999

A new 5th generation adhesive system(ONE-STEP) has been supplied which operators can apply to conditioned tooth surfaces by one simplified step. The purpose of this study was to determine whether different methods of adhesive application and various air drying duration after applying adhesive affect the shear bond strength of composite resin to dentin, and to evaluate the adhesive pattern of composite resin and dentin under SEM. Seventy-seven extracted human molar teeth were cleaned and mounted in palstic test tubes. The occlusal dentin surfaces were exposed with Diamond Wheel Saw and smoothed with Lapping and Polishing Machine (South Bay Technology Co., U.S.A.). Teeth were randomly divided into 7 groups (n=11), In experimental A group, adhesive was applied to dentin with agitation for 20 sec. In experimental N-A group, adhesive were continuously applied to dentin for 20 sec. Also control and experimental 1, 2, 3, 4 groups were dried for 10, 0, 5, 20, 30 seconds after applying adhesive, respectively, Adhesives were light cured for 10 sec. A gelatin capsule 5mm in diameter was filled with Aelitefil$^{TM}$ composite resin, placed on the treated dentin surface and light cured for 40 see, from three sides, All specimens were stored in distilled water at room temperature for 24 hours. The shear bond strengths were measured using a universal testing machine(AGS-1000 4D, Japan) at a crosshead speed of 5mm/min. An one-way ANOVA and LSD test were used for statistical analysis of the data. For SEM evaluation, seven specimens were made and sectioned. Representive postfracture and seven specimens were mounted on brass stubs, sputter-coated with gold and observed under SEM. The results were as follows : 1. The shear bond strength of experimental A group which adhesive were applied to dentin with agitation was higher than that of experimental N-A group (continuous application), and there was significant difference between two groups (p<0.01). 2. The interface between composite and dentin according to different application methods showed close adaptation in experimental A group and showed tinny gap in experimental N-A group. 3. The shear bond strength accoding to various air drying duration was the lowest value(7.57${\pm}$2.60 MPa) in experimental 1 group, so there was significant difference between experimental 1 group and other four groups (p<0.05). But there was no significant difference of shear bond strength between four groups (p>0.05). 4. The interface between composite and dentin according to various air drying duration showed close adaptation in control group and tinny gap in experimental 3 and 4 groups. But experimental 1 and 2 groups showed $30{\mu}$ and 6 - $10{\mu}m$ thick gaps, respectively.

• 구강회복응용과학지
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• 제25권4호
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• pp.437-444
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• 2009

본 연구에서는 여러 automixing 레진시멘트의 물성과 상아질에 대한 전단결합강도를 평가, 비교하고자 하였다. Self-adhesive automixing 레진시멘트인 Rely-X Unicem(3M ESPE, St. Paul, USA), Embrace resin cement(Pulpdent, Oakland, USA)와 chemical polymerizing automixing 레진시멘트인 Resiment Ready-Mix(J.L.Blosser Inc., Liberty Missouri, USA)를 사용하였다. 물성을 평가하기 위하여 레진시멘트를 테프론 주형에 주입한 후 자가중합을 시키고 24시간 동안 빛이 차단된 상태로 100% 상대습도에 보관 후 만능 시험기를 이용하여 압축강도, 간접인장강도, 굴곡강도를 측정하였다. 상아질에 대한 전단결합강도를 평가하기 위하여 발거한 하악 제3대구치의 협측 상아질을 노출 시킨 후 일정한 크기로 레진시멘트를 부착시킨 뒤 만능 시험기를 이용하여 전단결합강도를 측정하였다. SPSS Ver 12.0(SPSS Inc., Chicago, IL, USA)을 사용하여 95% 유의수준에서 One way ANOVA test로 분석하였으며 Scheffe test로 사후검정 하였다. 연구결과, chemical polymerizing automixing 레진시멘트가 self-adhesive automixing 레진시멘트에 비해 상대적으로 높은 물리적 성질과 상아질에 대한 전단결합강도를 보였다.

• Journal of Welding and Joining
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• 제33권4호
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• pp.44-49
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• 2015

The structural epoxy adhesive used in car body assembly needs the highest level of joint mechanical strength under lap shear, T-peel and impact peel conditions. In this study, the effect of nano functionalized block copolymer addition on the impact peel strength of epoxy adhesive was investigated. DSC analysis showed that the addition of nano functionalized block copolymer did not affect the curing reaction of epoxy adhesive. From single lap shear test, it was found out that the addition of nano functionalized block copolymer slightly decreased the cohesive strength of cured adhesive layer. The addition of nano functionalized block copolymer showed beneficial effect on T-peel strength by changing the adhesive failure mode to the mixed mode. However, the addition of nano functionalized block copolymer just decreased the room temperature impact peel strength. It was considered that the addition of nano functionalized block copolymer could have effect on disturbing the crack propagation only for the case of slow strain rate.

• Restorative Dentistry and Endodontics
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• 제43권1호
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• pp.7.1-7.7
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• 2018

Objectives: The aim of this study is to compare the shear bond strengths of ceramic brackets bonded to zirconia surfaces using different zirconia primers and universal adhesive. Materials and Methods: Fifty zirconia blocks ($15{\times}15{\times}10mm$, Zpex, Tosoh Corporation) were polished with 1,000 grit sand paper and air-abraded with $50{\mu}m$ $Al_2O_3$ for 10 seconds (40 psi). They were divided into 5 groups: control (CO), Metal/Zirconia primer (MZ, Ivoclar Vivadent), Z-PRIME Plus (ZP, Bisco), Zirconia Liner (ZL, Sun Medical), and Scotchbond Universal adhesive (SU, 3M ESPE). Transbond XT Primer (used for CO, MZ, ZP, and ZL) and Transbond XT Paste was used for bracket bonding (Gemini clear ceramic brackets, 3M Unitek). After 24 hours at $37^{\circ}C$ storage, specimens underwent 2,000 thermocycles, and then, shear bond strengths were measured (1 mm/min). An adhesive remnant index (ARI) score was calculated. The data were analyzed using one-way analysis of variance and the Bonferroni test (p = 0.05). Results: Surface treatment with primers resulted in increased shear bond strength. The SU group showed the highest shear bond strength followed by the ZP, ZL, MZ, and CO groups, in that order. The median ARI scores were as follows: CO = 0, MZ = 0, ZP = 0, ZL = 0, and SU = 3 (p < 0.05). Conclusions: Within this experiment, zirconia primer can increase the shear bond strength of bracket bonding. The highest shear bond strength is observed in SU group, even when no primer is used.

• 한국자동차공학회논문집
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• 제5권2호
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• pp.87-93
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• 1997

The bonding strength evaluation of light weight materials for electrical vehicle applications has been performed through single lap joint tests in which the design parameters such as fillet, joint style, adherend, bonding overlap length,bonding thickness, and environmental condition(soaking time in $25^{\circ}C$ water) are considered. It is experimentally oberved that lap shear strength of joint increases for higher fillet height, longer overlap length, and thinner bonding layer thickness. Al-Al adherend combination shows much higher lap shear strength than AL-FRP and FRP-FRP adherend combinations. Riveting at adhesive bonded joint of AL-AL adherend combination makes lap shear strength decrease. Effect of soaking time on lap shear strength is negligible.

• 한국해양공학회지
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• 제24권1호
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• pp.146-152
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• 2010

Recently, the applied frequency of composite materials was increased from the viewpoint of lightweight, high strength and low cost when a leisure boat and a fishing boatwere built. However, studies on the mechanical properties of composite material with ship are rare. Specially, a leisure boat and fishing boat with FRP had been built by hand lay-up method. However, the vacuum infusion method is rising recently for ship building. The manufactured these FRP plates were combined by using the adhesive. Therefore, in this study Cleavage peel strength, Shear strength and fatigue limit of adhesive bonds by tensileloading were estimated. From test results, the strengths of FRP specimens made by the vacuum infusion method are higher than that of the hand lay-up method.

• 대한치과보철학회지
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• 제44권4호
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• pp.383-393
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• 2006

Statement of problem : Limited research on flowable resin has been undertaken on its application directly on dentin associated with the adhesive systems. Purpose : This study was to evaluate the shear bond strengh and fracture aspect of flowable resin on human dentin with various types of dentin bonding adhesives with thermo cycling effect. Materials and methods: Filtek-Flow(3M ESPE, USA) was used as flowable resin and Eighty human molars were randomly divided into 4 groups : three dentin bonding adhesives (Scotchbond-Multipurpose : 3-step contentional system, One-Step : One-bottle system. Prompt L-Pop : All-in-one, self-etching primer) and 32% etching treatment without bonding adhesive as a control group. For evaluating their durability of bonding, each group was subdivided : storaging in the water at 37$^{\circ}C$(24 hours) and thermocycling (0$^{\circ}C$-55$^{\circ}C$, 30 seconds intervals, 1000 cycle). Shear bond strength tests were performed and resin-dentin interface and fracture mode were observed. Results were analysed by one-way ANOVA and Scheffe's multiple range test. Results and Conclusion : 1. At 0 cycle, the mean shear bond strength of One-Step exhibited the highest value of all groups(p<0.05), and there were no significant differences between Prompt L-Pop and Scotchbond-Multipurpose, Scotchbond-Multipurpose and control(p>0.05). After 1000 thermocycling, One-Step exhibited higher value than other groups(p<0.05), and there were no significant differences among other groups (p>0.05). 2. The shear bond strength of each group was significantly decreased after thermocycling except Scotchbond-Multipurpose (p>0.05). 3. The most common failure mode was adhesive type and mixed type, next in order.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.115-120
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• 2008

In this study, effects of surface roughness on adhesive strength of heat-resistant adhesive RTV88 were examined. Sandblast was used to generate rough surfaces on aluminum adherends, and then tensile-shear tests of Al/RTV88 single lap joints were performed. The shear strength was shown to be affected by the surface roughness. Effective area, peel failure area, and cohesive failure area were introduced to explain the effects of surface roughness on the adhesive strength. An empirical relation for the failure force was proposed based on these parameters and verified by the test results.

• Journal of the Korean Wood Science and Technology
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• 제12권1호
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• pp.38-43
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• 1984

Water soluble urea-melamine-phenol copolymer adhesive manufactured with 80 percent of urea resin contents was manufactured by different molar ratio for a high temperature curing type, and their properties and strengthes were examined through manufactures of plywood with Kapur (Dryobalanops spp.) veneers. The results are summarized as follows: 1. Specific gravities of air dried plywood manufactured from each adhesive ranged from 0.78 to 0.84 and their moisture contents met the KS requirement. 2. In dry and wet shear strength, $U_{80}M_{10}P_{10}$ copolymer resin showed the highest value and urea resin was the lowest, indicating that melamine and phenol were effective for increasing glue shear strength of urea resin. 3. In case of glue shear strength after boiling test, phenolic resin was the nest and melamine was not so effective as phenol on reinforcement of boiling water resistance of urea resin.

• 폴리머
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• 제38권3호
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• pp.397-405
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• 2014

본 연구는 고성능 준구조용 양면 점착테이프 제조를 위해 2-ethylhexyl acrylate(2-EHA)와 acrylic acid(AAC)를 사용하였고, UV 조사에 의해 시럽을 준비하였다. 양면 점착테이프의 두께, 무기물 충전제 함량 및 충전제 종류에 따른 준구조용 물성에 미치는 영향을 고찰하였다. 테이프의 두께 및 젖음시간이 증가할수록 박리강도가 증가하였다. 두께가 얇은 점착테이프($250{\mu}m$이하)의 경우 무기물 충전제의 true density가 낮을수록 적용시간 경과에 따라 박리강도가 높게 나타났다. 무기물 충전제 입자가 클수록 초기 박리강도가 높게 나타났으며, SEM 이미지를 통해 점착테이프 내에 무기물 충전제의 크기를 확인하였다. 다양한 무기물 충전제 및 함량에 따라 박리강도 증가와 함께 전단접착강도가 증가하는 비례관계를 보였으며, $0.1{\mu}m$인 양면 점착테이프에서 무기물 충전제는 전단접착강도에 더 영향을 주었다. 이러한 결과로부터 박막형 아크릴 양면 점착테이프는 준구조용 물성을 필요로 하는 용도에 사용가능할 것으로 사료된다.