• Journal of the Korean Applied Science and Technology
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• v.36 no.2
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• pp.524-530
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• 2019

In this study, polyether polyol polypropylene glycol and isophorone diisocyanate (IPDI) were synthesized based on polyrupopylene mono methyl eher (PM) for the synthesis of water - soluble polyurethane for coating on leather skin layer. After synthesis of prepolymer, PM was added at $40^{\circ}C$ to 1M, 2M, 3M, and 4M to inhibit the viscosity rise, and neutralization reaction and chain extension reaction were carried out to prepare polyurethane samples. According to the measurement results of the tensile strength, elongation and adhesive strength of the prepared sample, the tensile strength was 2.109 kgf / mm2 for PM 1M, 1.721kgf / mm2 for 4M, elongation was 496% for PM 1M, 522% for 4M, adhesion was 1.114 kgf / cm for PM 1M and 0.99 kgf / cm for 4M.

• Journal of Adhesion and Interface
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• v.17 no.1
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• pp.7-14
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• 2016

Epoxy composites with concentrations of 5-70 wt% of silica particles were prepared in order to improve mechanical property and poor thermal stability. The mechanical and thermal properties were investigated and compared to the corresponding properties of neat epoxy composite. Furthermore, the effects of silane compound treatment on silica particles were observed by the experimental results of the tensile strength, glass transition temperature, and thermal stability of epoxy composite. Tensile strength of epoxy composites was measured by universal testing machine (UTM) and after that, the structure and morphology analysis of epoxy nanocomposites were analyzed by field emission scanning electron microscope (FE-SEM) and energy dispersive spectroscopy (EDS). The increased solid content of CA0030 particle improved the tensile strength of epoxy/ modified composites to give 30-50 MPa. The thermal expansion coefficients (CTE) of neat epoxy resin and epoxy/silica composites measured with a thermomechanical analyzer (TMA) showed that the incorporation of silica particles was helpful to reduce the CTE of neat epoxy resin.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.05a
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• pp.216-219
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• 1995

One of the principal problems encountered in the use of glass fiber reinforced Plastic composites(GFRP) is to establish an active fiber surface to achieve maximum adhesion between resin and fiber surface. In order to develope new process to overcome the disadvantage of chemical agent, we have studied the effect of reactive plasma glass surface treatment on the electrical and mechanical properties of glass fiber reinforced epoxy composites. It is found that the electrical and mechanical characteristics of the composites treated with plasma is improved especially in the dielectric strength by 20% and tensile strength by 15%, whereas the tan $\delta$ is decreased significantly.

• Elastomers and Composites
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• v.16 no.4
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• pp.211-216
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• 1981

A series of conveyer rubber belts has been made by blending natural rubber(NR), styrene butadiene rubber(SBR), chloroprene rubber(CR) and additives on nylon cords, and their respective flammability has been investigated. It has been observed that: 1. By adding an antiflame agent to the belt, in addition to 70% chlorinated paraffine and antimony oxide($Sb_{2}O_{3}$), the inflammability is improved remarkably to O - 2 seconds due to the synergistic effect, while a sample without antiflame B fails to pass the KS M 6678 test. 2. Physical properties, such as tensile strength, elongation at break and adhesion strength, of the sample belts have been studies by varying ratios of NR/CR from 20 to 100, and it has been observed that the higher ratios have the better physical properties.

• Textile Coloration and Finishing
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• v.28 no.3
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• pp.183-188
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• 2016

The uniformly dispersed p-Aramid chopped fiber in a variety of rubber was investigated. The cross section and surface properties in a variety of rubber were characterized by scanning electron microscopy(SEM), weight, tensile strength, cold resistance measurements. The 1mm p-Aramid chopped fiber better uniformly dispersed than the other p-Aramid chopped fiber. The p-Aramid of lmm chopped fiber showed excellent adhesion in rubber composite because of homogeneous dispersion. Consequently, the best 1mm chopped fiber and rubber improved the strength of the composite.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.529-532
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• 2005

The effects of polymer-binder ratio and ceramic powder content on the drying shringage and strength of polymer-modified pastes using redispersible polymer powders and ceramic powder are examined. As a result, the drying shrinkage of the polymer-modified pastes using redispersible polymer powders tend to decrease with increasing polymer-binder ratio and ceramic powder content. Regardless of the type of polymer powder, the tensile strength and adhesion in tension of the polymer-modified pastes with ceramic powder tend to increase with increasing polymer-binder ratio and ceramic powder content.

• Design & Manufacturing
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• v.17 no.2
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• pp.42-46
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• 2023

Currently, fossil resources are depleting rapidly. We are looking for energy to replace fossil fuels. They are trying to use electricity to replace internal combustion locomotives. Secondary battery raw materials and chemical additives are pulverized by the high-speed rotation of the grinding disc of the Classifier Separator Mill. Grinding Disc Assembly requires characteristics to withstand abrasion, corrosion, high-speed rotational force and impact. Domestic and foreign grinding discs were analyzed through abrasion resistance, hardness, bending strength, and tensile adhesion strength tests.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.21-22
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• 2013

Nowadays, the fiber which mixed with concrete matrix always has low adhesion with cement paste. It's difficult to use fiber to reinforce the structure. For more adding fiber in concrete would cause some problems as the low flowability and surface polishing. Further study is needed in fiber using. In this research, further study in fiber reinforced concrete has been invested. Various fibers with different properties have been used to prevent cracking. Fiber reinforced concrete's fundamental properties as slump, air content, compressive strength and tensile strength have been tested. Optimum type of the fiber and optimum addition ratio of fiber has been invested to increase the utility of the fiber which used in concrete.

• Nuclear Engineering and Technology
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• v.48 no.1
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• pp.182-188
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• 2016

In this paper, a feasible strategy for the recycling of nuclear graphite is reported, based on the formation mechanism and the removal of carbon-14 by micro-oxidation. We investigated whether ground micro-oxidation graphite could be used as a filler to make new recycled graphite and which graphite/pitch coke ratio will give the recycled graphite outstanding properties (e.g., apparent density, flexural strength, compressive strength, and tensile strength). According to the existing properties of nuclear graphite, the ratio of graphite to pitch coke should not exceed 3. The recycled reactor graphite has been proven superior in density, strength, and thermal conductivity. The micro-oxidation process enhances the strength of the recycled graphite because there are more pores and unsmooth surfaces on the oxidized graphite particles, which is beneficial for the access of the pitch binder and leads to efficient joint adhesion among the graphite particles.

• Elastomers and Composites
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• v.44 no.3
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• pp.282-289
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• 2009

The pressure-sensitive adhesive(PSA) tapes are widely used as floor-sealing material in Korean constructive industry. However, the general PSA tapes can not seal the apertures completely. This is one of main reasons to cause imperfect finishing. In order to solve the problems, the asphalts were modified by FKM powder and SBS in this study. The physical properties of modified asphalts were examined by measuring the softening point, viscosity, tensile strength and adhesion strength of FKM and SBS modified asphalt. The softening point of SBS modified asphalt was increased greatly due to the formation of network structure in asphalt. Also, the change of adhesion strength of SBS modified asphalt with temperature was not so great comparing to those of pure asphalt and FKM modified asphalt. The best results of pressure-sensitive adhesion could be obtained by the SBS(linear) modified asphalt containing 6 wt.% of linear type SBS.