• 펄프종이기술
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• 제48권3호
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• pp.51-56
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• 2016

The most widely used glue in a corrugator is starch, which is a natural polymer. This material needs thermal energy to achieve a binding force, so a heating section is installed in a corrugator. However, this heating section can cause quality problems in linerboards and corrugating medium and increase the production cost because of the high cost of fossil resources. Therefore, a new adhesive that provides the binding force at lower temperatures than the conventional one must be developed. In this study, SB-latex was selected as a co-adhesive and added to the starch solution. The addition of the SB-latex was determined based on the viscosity of the new adhesive. The adhesive strength and the drying energy reduction of a corrugated board were measured to evaluate the functionalities of the new adhesive. The addition of SB-latex was determined to be under 20% of the oven-dried starch based on the viscosity of the new adhesive. The adhesive strength was improved and the drying energy was reduced by applying the new adhesive.

• 한국광학회지
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• 제13권4호
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• pp.332-335
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• 2002

가류고무의 접착력을 향상시키기 위해서 엑시머 펄스 레이저 광으로 표면처리를 하였다. 레이저 광 조사 수의 증가에 따라, 접착력은 크게 향상되어, 100회의 조사 수에서 1500 N/m의 가장 큰 값을 얻었다. 또한 에너지 밀도 증가에 대해서도 접착력은 증가하여 에너지 밀도 176 mJ/$cm^{2}$에서 가장 큰 접착력 1500 N/m를 얻게 되었다. 에너지 밀도의 증가에 따라 접착력이 증가하는 것은 표면적의 증가와 관련이 있음을 알았다.

• Macromolecular Research
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• 제12권5호
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• pp.540-543
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• 2004

Surface treatment using an excimer pulse laser beam has been conducted in order to increase the adhesive strength of vulcanized rubber. The adhesive strength increased with increasing the number of irradiation time with laser pulses and reached to 1,500 N/m after 100 cycles of irradiation. Increased in energy density was directly proportional to the improvement of the adhesive strength. Maximum value of the adhesive strength of 1,500 N/m obtained at the energy density of 176 mJ/$\textrm{cm}^2$. We conclude that an increased energy density improves in both the surface area and adhesive strength.

• Elastomers and Composites
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• 제52권1호
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• pp.22-26
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• 2017

The thermal conductivity and the adhesive properties were measured, after synthesis of thermal conductive composite which was obtained as a result of mixing alumina or graphite with acrylic adhesive synthesized by UV polymerization. The adhesive properties of the composite were evaluated measuring the peel strength at 180 degrees, the retention, and the initial tack;the thermal conductivity was estimated using laser flash analysis. As the filler contents increased, a decrease in peel strength and initial tack and an increase in retention and thermal conductivity were observed. When compared to alumina, the adhesion of graphite showed a dramatic decrease, whereas the thermal conductivity was further enhanced. It was found out that the small size of graphite increased the mechanical interlocking between the polymer and the filler, and it was easier for graphite to come into contact with other graphite in the matrix.

• Journal of the Korean Wood Science and Technology
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• 제30권3호
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• pp.34-41
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• 2002

This study investigated the thermogravimetric analysis of two types of cured tannin-based adhesives from wattle and pine, with three hardeners of paraformaldehyde, hexamethylenetetramine and TN (tris(hydroxyl)nitromethan), at a temperature of 170℃ and a heating rate of 5, 10, 20 and 40℃/min for 10 minutes. The 5 minutes cured wattle tannin-based adhesive with each hardener at 170℃ was also tested to compare the degree of curing. It was found that thermogravimetric analysis could be used to measure the degree of curing of a thermosetting adhesive. The TG-DTG curves of all the adhesive systems were similar and showed three steps in a similar way to a phenolic resin. This means that each adhesive system is well cross-linked. However, a high thermal decomposition rate was shown at 150 to 400℃ in the case of the pine tannin sample with TN (tris(hydroxyl)nitromethan). The Flynn & Wall expression was used to evaluate the activation energy for thermal decomposition. As the level of conversion (𝛼) increased, the activation energy of each system increased. The activation energy of the wattle tannin-based adhesive with paraformaldehyde was higher than the others.

• 한국도로학회논문집
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• 제17권6호
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• pp.47-54
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• 2015

PURPOSES : The objective of this study is to evaluate the early adhesive characteristic of asphalt emulsions, including polymer-modified emulsions, for chip seals using the surface energy concept, the bitumen bond strength (BBS) test, and the Vialit test. METHODS : Two general methods, the BBS test and Vialit test, were applied to investigate the bond strength and the aggregate loss, respectively. A new theory, the surface free energy (SFE) theory, was used to evaluate the adhesive characteristic between the emulsion and the aggregate. Based on the theory, the contact angles were measured, and then the surface energy components were calculated. Using those components, the work of adhesion (Wa) was calculated for each emulsion. To ensure reliable results, all the tests were performed under the same conditions, i.e., at $25^{\circ}C$ for 240 minutes of curing time. For the materials, three emulsions (CRS-2, CRS-2L, and CRS-2P) and one aggregate type (granite) were employed. RESULTS AND CONCLUSIONS : Under the same conditions, the modified emulsions showed better adhesive characteristics and curing behaviors than the unmodified emulsions. In addition, there was no significant difference between the various modified emulsions. One of the important findings is that the analysis by Wa presents more sensitive results than other methods. The results of the Wa showed that the CRS-2P emulsion has the best adhesive characteristics. Consequently, the use of modified emulsions for chip seals could prevent aggregate loss and allow open traffic earlier.

• 유변학
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• 제8권2호
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• pp.129-138
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• 1996

접착강도는 접착제의 점탄성을 반영한 온도·속도 의존성을 나타낸다는 것이 잘 알 려져있다. 특히 유리전이온도(Tg)에서의 역학적 완화기구가 접착층의 변형을 수반하는 접착 층의 변형을 수반하는 접착강도에 크게 영향을 미치고 있다. 또한 접착계의 모드I의 변형에 너지 해방율(GIC)를 측정할때에도 접착제의 변형과 파괴가 발생하기 접착제의 점탄성이 그 값에 어떠한 영향을 미치는 지에 흥미가 깊다. 본 연구에서는 2종류의 에폭시 수지를 블랜 드한 접착제를 이용하여 일정한 측정조건에서 인장 접착강도와 GIC의 상관관계에 대하여서 도 토론하였다.

• 접착 및 계면
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• 제21권2호
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• pp.65-70
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• 2020

각각의 다른 복합재료를 연결하는 데 주로 에폭시 접착제가 사용되고 있다. 에폭시 접착제 대표적인 열경화성 수지로서 에폭시와 경화제의 경화 반응을 통해 선형구조에서 3차원의 망상 구조로 변하게 되어 접착을 한다. 경화제의 종류에 따라 비율 및 경화 조건 등이 변하며, 이러한 조건에 따라 물성이 달라진다. 접착공정이 대형화 됨에 따라 접착제를 바르고 즉시 접착하지 못하기 때문에, 대기시간동안 습도 및 온도 등 외부환경에 영향을 받아 접착제의 접착력 저하로 이어지게 된다. 본 논문에서는 유리섬유강화 복합재료에 에폭시 접착제를 사용하여 접착하였고, 단일 랩 전단 시험을 통하여 가사시간에 따른 에폭시 접착제의 접착강도를 평가하였다. 가사시간에 따른 접착력 변화를 확인하기 위하여, 복합재료에 에폭시 접착제를 바르고 상온에서 각 시간에 따라 대기한 후 접착하였다. 단일 랩 전단 강도를 통하여 일정시간 이상 가사시간을 오래 둘 수록 접착강도가 감소한다는 것을 확인하였다. 습도조건에 따른 접착력 변화를 확인하기 위하여, 경화습도 조건을 항온항습기로 조절하여 경화 시켰고, 습도조건에 따른 접착 강도를 단일 랩 전단 시험을 통해 접착력을 평가하였다. 적은 양의 수분은 에폭시 접착제의 경화 반응을 가속시켜 접착 강도를 증가시켰으나, 일정 이상의 과도한 수분은 오히려 접착강도를 감소시킴을 확인하였다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 춘계학술대회 논문집
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• pp.175-176
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• 2010

• 한국정밀공학회지
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• 제20권3호
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• pp.157-164
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• 2003

The pulse-echo method is one of the most widely used ultrasonic techniques for application of nondestructive evaluation. Particularly, quantitative nondestructive evaluation of defects has been considered more important to assure the reliability and the safety of structure. Frequency energy in adhesive joints is based on the ultrasonic wave analysis. The attenuation coefficient upon wave amplitude and the frequency energy that is expressed in the term of wave pressure amplitude were utilized for the primary wave experiment. By means of a control experiment, it was confirmed that the variation of the frequency energy in adhesive joints depends on transition by stress variation. In this paper, the ultrasonic characteristics were measured for single lap joint and Double Cantilever Beam specimen with different fracture modes that was subjected to stress. Consequently, the data that was obtained from the adhesive specimen was analytically compared to the fracture mechanics parameter