• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.299-304
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• 2003

In this research, eight waterproofing membranes were selected from commercial market and the tensile adhesive characteristics of the waterproofing system (WPS) on concrete bridge deck were investigated in view of various factor in asphalt pavement. Tensile adhesive strength (TAS) test of different asphalt pavement types showed that TAS of WPS under SMA (Stone Mastic Asphalt) pavement was greater than that under dense asphalt pavement. Tensile adhesive strength (TAS) of sheet membranes was improved as the compaction temperature of asphalt concrete increase, but TAS of liquid membranes were not. TAS of sheet membranes after wheel tracking test were in the order of the sites under wheel path (UWP), before wheel tracking (BWT) and nearby wheel path (NWP), Since TAS of the same WPS of UWP was higher than TAS of BWT, wheel loading had function of pressing WPS resulting in higher adhesive strength, But liquid membranes were variable on types, The feature of detached interface after T AS test showed that sheet types were all detached in between deck concrete and WPS, and liquid types were detached in between asphalt pavement and WPS,

• Journal of Adhesion and Interface
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• v.19 no.4
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• pp.173-176
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• 2018

• Journal of Adhesion and Interface
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• v.23 no.1
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• pp.1-7
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• 2022

As the wind blades become larger, they tend to be made by mixing glass fiber and carbon fiber, and it is important to increase the properties of the adhesive which adheres the two materials. The physical properties of the adhesive vary depending on the content of the additive and curing conditions. In this study, the change in adhesion strength with the difference between the CNT (Carbon Nanotube) content of the epoxy adhesive and the humidity during curing was evaluated. GFRP and CFRP specimens were prepared and adhered using an epoxy adhesive, and to examine changes in characteristics with carbon nanotube contents and with the humidity during curing of the epoxy adhesive, adhesion strength was evaluated by dividing the difference between carbon nanotube content and humidity. To find out the change with the CNT contents, the intelaminar shear strength (ILSS) test was performed by dividing the contents of the CNT into 0, 0.1, 0.3, 0.5, and 1 wt%, and to confirm the change with the humidity conditions, the adhesive was cured by dividing the humidity by 20, 50, and 80%. From the result of the experiment, the adhesive force decreased when the content was excessively large, although the adhesive property was enhanced by adding CNT to the epoxy adhesive. In addition, it was confirmed that the adhesion characteristics were not changed as the humidity increased.

• The korean journal of orthodontics
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• v.22 no.2 s.37
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• pp.449-474
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• 1992

The purpose of this study was to evaluate the in vitro shear bond strengths to enamel and the failure sites of three ceramic brackets and one metal bracket in combination with light cured orthodontic adhesive. The brackets were divided into four groups. Each ceramic bracket group had different bonding mechanisms with adhesive. Group A; metal bracket with foil-mesh base (control group) Group B; ceramic bracket with micromechanical retention Group C; ceramic bracket with chemical bonding Group D; ceramic bracket with mechanical retention and chemical bonding. Forty extracted human lower first premolars were prepared for bonding and 10 brackets for each group were bonded to prepared enamel surfaces with $Transbond^{\circledR}$ light cured ortho dontic adhesive. Twenty four hours after bonding, the Instron universal testing machine was used to test the shear bond strength of brackets to enamel. After debonding, brackets and enamel surfaces were examined under stereoscopic microscope to determine the failure sites, Statistical analysis of the data was carried out with ANOVA test and $Scheff\acute{e}$ test using SPSS PC+. The results were as follows. 1 . There were statistically significant differences in mean shear bond strengths of three ceramic bracket groups (p < 0.05). Shear bond strengths of group C and D were significantly higher than that of group B and shear bond strength of group C was significantly higher than that of group D. 2. Group C and D both had significantly higher shear bond strengths than metal bracket (group A), but there were no significant differences in shear bond strengths between group A and B (p < 0.05). 3. The failure sites of four bracket groups were also different. Group C and D failed primarily at enamel-adhesive interface, but group A and B failed primarily at bracket base-adhesive interface. 4. Among all ceramic bracket groups, group B was very similar to metal bracket in the aspect of shear bond strength and failure site.

• Journal of Adhesion and Interface
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• v.7 no.4
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• pp.1-9
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• 2006

The single lap joint is the most studied joint in the literature in terms of both theory and practice. It is easy to manufacture and the lap shear strength is a useful value for strength assessment and quality control. Simple design rules exist such as the one present in standard ASTM 1002 or in a recent paper by Adams and Davies. The main factors that have an influence on the lap shear strength are the type of adhesive, i.e. ductile or brittle, the adherend yield strength and the overlap length. The overlap increases the shear strength almost linearly if the adhesive is sufficiently ductile and the adherend does not yield. For substrates that yield, a plateau is reached for a certain value of overlap corresponding to the yielding of the adherend. For intermediate or brittle adhesives, the analysis is more complex and needs further investigation. In order to quantify the influence of the adhesive, the adherend and the overlap on the lap shear strength, the experimental design technique of Taguchi was used. An experimental matrix of 27 tests was designed and each test was repeated three times. The influence of each variable could be assessed as well as the interactions between them using the statistical software Statview. The results show that the most important variable on the lap shear strength is the overlap length followed by the type of adherend.

• The korean journal of orthodontics
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• v.12 no.2
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• pp.139-144
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• 1982

As adhesive systems were improved, a great variety of bracket bases were available. The purpose of this study was to evaluate the adhesive porperties of 3 types of direct-bonding brackets by testing the tensile stremgth. 60 noncarious premolars extracted for orthodontic treatment were used. The tensile strength was tested by Tensilon/UTM-1-10000C after 24 hours from bonding. Following results were obtained; There was no difference between the tensile strength of foil-mesh base bracket and photoetched base bracket statisstically. However, the accurate test result of plastic bracket could not be obtained due to the distortion of bracket wing during testing. Of the failure in fail-mesh base bracket and photo-etched base bracket, the combination type of failure, where part of the adhesive remained on the tooth and part on the bracket was the most common type (50%, 50%), The second type of failure occured at the bracket-adhesive interface (30%, 35%) and the last type of failure occured at the adhesive-tooth interface (20%, 15%).

• Journal of Adhesion and Interface
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• v.4 no.3
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• pp.9-13
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• 2003

In this paper, the effects of crosslinking agent and pH controlling agent on adhesive properties and water solubility of water soluble acrylic pressure sensitive adhesives were studied by adding the crosslinking agents or pH controlling agents after the polymerization. the tack, cohesive strength, and peel strength were measured to evaluate adhesive properties. the turbidity was also measured to evaluate water solubility of pressure sensitive adhesives. When crosslinking agent was added less than 0.2 wt%, tack increased and cohesive strength and peel strength decreased with increasing concentration. When crossinking agent was added more than 0.2 wt%, the results were opposited. When pH controlling agent was added, tack and water solubility decreased and peel strength and cohesive strength increased with increasing concentration. the influence of pH controlling agents on adhesive properties and water solubility of pressure sensitive adhesive increased in the order of lithium hydroxide, potassium hydroxide and sodium hydroxide.

• Journal of Adhesion and Interface
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• v.19 no.3
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• pp.118-122
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• 2018

In this study, polyurethane hot melt adhesive containing ester groups was synthesized. Three kinds of chain extenders were used to find out the best chain extender. Results showed that adhesive containing 1,4-butanediol as a chain extender exhibited the highest peel strength among them. Also, it was found that there existed the optimum molecular weight of 1,4-butanediol containing adhesive for make the highest peel strength.. Moreover, hot melt adhesive containing 1,4-butanediol chain extender was applied to various kinds of textiles substrate such as cotton, polyester, and urethane coated polyester textiles to study the effects of different substrates on the peel strength and water resistance at $60^{\circ}C$. It was found that cotton substrate showed the highest peel strength and urethane coated polyester substrate showed the highest resistance on $60^{\circ}C$ water.

• Journal of the Microelectronics and Packaging Society
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• v.25 no.4
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• pp.111-118
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• 2018

In order to develop a local stiffness-variant stretchable substrate with the soft PDMS/hard PDMS/FPCB configuration consisting of two stiffness-different polydimethylsiloxane (PDMS) parts and flexible printed circuit board, a FPCB was bonded to PDMS using the acrylic-silicone double-sided tape and the interfacial adhesion of the PDMS/FPCB was evaluated. The pull strength of the FPCB, which was bonded to the fully cured PDMS using the silicone adhesive of the double-sided tape, was 259 kPa and the delamination during the pull test occurred at the interface between the PDMS and the silicone adhesive. On the contrary, the bonding process, for which the FPCB was bonded using the silicone adhesive to the PDMS partially cured for 15~20 minutes at $60^{\circ}C$ and then the PDMS was fully cured for 12 hours at $60^{\circ}C$, exhibited the remarkably enhanced pull strength of 1,007~1,094 kPa. With the above mentioned bonding process, the delamination during the pull test was observed at the interface between the FPCB and the acrylic adhesive of the acrylic-silicone double sided tape.

• Journal of Adhesion and Interface
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• v.21 no.4
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• pp.135-142
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• 2020

Recently, people's interest in eco-friendly plastics derived from nature to replace petroleum-based plastics is increasing due to environmental problems such as microplastics. In line with this trend, eco-friendly adhesives using natural materials and processes are also being developed in the adhesive field. Among them, maltose is a natural substance derived from starch and is the main component of starch syrup used as a food additive. Due to its lower molecular weight than starch, it is easily soluble in water, and above all, there is a possibility that it can be copolymerized with other monomers through solution polymerization. However, researches related to the application of maltose to adhesives are very rare. In this study, after modifying maltose using acrylic anhydride, the product was analyzed through FT-IR and H-NMR. And the modified maltose was copolymerized with two kinds of acrylic monomers. The synthesized adhesive was applied on the wood and the adhesive performance were investigated.