• Transactions on Electrical and Electronic Materials
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• v.7 no.6
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• pp.283-292
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• 2006

So that high-strength and electrical properties apply by excellent high voltage insulator electricity material, ATH content and platinum-based flame retardant that influence in flame retardant and tracking characteristic among composite of silicone rubber studied mechanical strength and influence getting to electrical properties. Composition of ${\alpha}$, ${\omega}-vinyl$ poly (dimethyl-methylphenyl) siloxane(VPMPS) of a polymer quantity made doing mole of D4, $D3^{Me,Ph}$ and VMS by 1000:15:0.2 mole ratio and uses basic catalyst tetramethylammonium silanolate(TMAS) and do opening equilibrium polymerization to be used to main polymer for high voltage insulation insulator. Control ATH content and content of platinum-based flame retardant and made high voltage insulation silicone rubber. Measured mechanical strength of making silicone rubber using UTM, and tracking characteristic according to standard of IEC 60587, flame retardant test studied effect that flame retardant characteristic gets in tracking characteristic, measuring according to UL94V method of test.

• Elastomers and Composites
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• v.46 no.1
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• pp.2-9
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• 2011

Permeability to gases and vapors is an important function in tires, rubber tubes and diaphragms. It mainly depends on the rubber material. Generally, permeability increases in the following order: silicone rubber > NR > EPDM > SBR > NBR > FPM > ECO > IIR. And, for an elastomer permeability is also very much dependent on compounding. Many research works are reported in the area of gas permeability for formed rubber,$^{1-7}$ however, few studies are found for unformed elastomer products. Incorporation of nano-particles, use of thermoplastic elastomers and applying high barrier multilayer coatings are the main approaches to obtain a high barrier elastomeric product. In this paper, barrier article for vehicle is introduced.

• Steel and Composite Structures
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• v.25 no.1
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• pp.57-65
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• 2017

The fatigue fracture of studs is the main reason for failure of composite beams based on massive engineering practices. Hence, studying the laws of cracks initiation and propagation are of great directive significance. eXtended Finite Element Method (XFEM) is an effective method in solving moving discontinuous problems in recent years. This paper extends our recent work on the fatigue damage analysis of stud shear connectors in the steel and crumble rubber concrete (RRFC) composite beams based on XFEM. The process of crack initiation to failure of the stud is simulated and an effective calculation criteria for the fatigue life of the composite beams is put forward. After the reliability of the numerical analysis is verified based on tests results, the extensive parametric study is conducted concerning effects of different rubber contents, shear connection degrees and the stress amplitudes. Results show that with the increasing rubber contents and shear connection degrees, the fatigue lives of composite beams increase obviously. Furthermore, the relationship between the fatigue life of the stud at the edge of the shear span and the whole composite beams is studied. Finally, the S-N curves of the single stud and the whole composite beams are put forward based on XFEM.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.509-512
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• 1999

The main problem in porcelain as a high voltage insulator is that the water film is felled on the insulator surface due to rain, flog, and dew. In the presence of contamination. leakage current increases which may lead to flashover that could be followed by an outage of the power system. These days, high voltage polymer outdoer insulators have been studied and widely used, because they have excellent electrical and mechanical properties, superior performance of flashover for contamination. light weight, easy installation or handling. no maintenance during service, competitive price, and so on. First of a1l the excellent performance of the silicone rubber in polluted and wet conditions is attributed to the ability of the material to maintain the hydrophobicity of the surface in the presence of severe contaminants and wet conditions. This is due to a low surface energy of the silicone rubber. But the leakage current and some surface discharge occurs on the surface of insulator when the insulator is used for a long time. So the leakage current and the surface discharge current are important lo estimate the condition of the silicone rubber surface. In this paper, the average leakage current the surface discharge current the surface rubber surface with the salt fog condition for the first stage.

• The Journal of Asian Finance, Economics and Business
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• v.6 no.2
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• pp.55-62
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• 2019

China has become the second largest economy since 2010. China's economy is supported by the rapid growth of its automobile industry. The rapid growth of the automobile and tire industry will increase the natural rubber (NR) demand as its primary raw materials. Although as a significant producer, China cannot fulfill the consumption by its domestic production. Thus China relies heavily on import from Southeast Asia countries as the primary producers of natural rubber in the world. China and Southeast Asia are dependent on their economy in terms of the availability of natural rubber as raw materials. But the economic slowdown in China since 2008 is expected to affect the international trading between China and Southeast Asia countries. This research aims to analyze the determinants of NR export from Southeast Asia to China using panel data analysis. The results show NR price, exchange rate, and China's economic slowdown significantly affect NR export to China, while Southeast Asian NR production has no significant effect. China as the main importer of NR from Southeast Asia has a big role in growing NR export in Southeast Asia. If China's economy doesn't improve soon, it will affect the economy in Southeast Asia.

• Steel and Composite Structures
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• v.41 no.5
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• pp.649-661
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• 2021

This paper presents experimental and analytical studies to understand the behavior of crumb rubber concrete (CRC)-filled fiber reinforced polymer (FRP) and steel tube double skin column (DSC) and beam (DSB) members under cyclic loading. The main test variable was the percentage of rubber which ranged from 0 to 40%. For column members, different heights corresponding to different aspect ratios were examined to understand the to understand the effect of DSCs' slenderness on the cyclic response of the columns. the. The behavior of the specimens in terms of failure mode, strain development, energy dissipation, load-displacement response were presented and compared. The ability of the current provisions of the Australian codes to predict the capacity of such double skin members was also evaluated based on the test results. This study concluded that the reduction in the concrete strength was more severe at the material level compared to structural level. Also, as the load changed from axial compression in columns to pure moment in beams the negative effect of rubber percentage on the strength became less significant.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2003.09a
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• pp.473-480
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• 2003

In these days, The base isolation system is often used improve the seismic capacity of the structure Instead of conventional techniques of strengthening the structural members. The purpose of this study is to evaluate dynamic property evaluation of control equipment using Lead Rubber Bearing. In this study, analysis numerical was performed to determine the optimal dynamic property of lead rubber bearing and damper which minimize the response of base from in main control room. Also the analytical results was composed with the test results peformed in previous study

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.11a
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• pp.145-151
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• 2008

URN(Underwater Radiated Noise) is one of the important performances of the battle ship related to the stealth. The main source of the URN is the structure-borne noise on the hull. And the pipe vibration transmitted to the hull is the main source of the structure-borne noise when the speed of the ship is lower than CIS(Cavitation Inception Speed). In this paper, the vibration isolator(rubber mount) for the pipe system is described in order to reduce the structure-borne noise transmitted to the hull. The vibrations on the sea-water conveying pipes and their supports are measured in order to know how much vibration occurs on those positions. Based on these test results, the improved design of the rubber mount is suggested by the parametric study and is verified numerically with the pipe and hull model.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.4A
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• pp.303-309
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• 2011

Laminated rubber bearing is the most commonly used device for seismic base isolation of bridge structures. It is important to know performance and behavior characteristics of the laminated rubber bearings. The main evaluation factors of the rubber bearing are classified as compressive, shear and tensile behavior characteristics. The reference data of compressive and shear characteristics are rich, but the reference data of tensile characteristics is scarce. In this study, tensile test results of the rubber bearing with variation of shape factor and shear deformation are investigated for mechanical property. When tensile deformation in normal condition is increasing, tensile cycle behavior curve becomes non-linear and tensile breaking point is 300%. On the other hand, tensile breaking point is shear deformation condition is about 40%. Furthermore, when shape factor is lower, tensile breaking point is decrease. This results mean that tensile breaking point is decreased in triaxial tensile deformation because of cracks caused by internal void of the rubber bearings. This experimental data can be used as the reference data of tensile characteristics for designing seismic isolation of structures.

• Elastomers and Composites
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• v.44 no.2
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• pp.122-133
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• 2009

Rubbers, such as natural rubber, polybutadiene, styrene-butadiene rubber, nitrile-butadiene rubber, chlorinated rubber and EPDM, have been continuously improved in response to a heavy demand and a new property requirement from industry. One of the best ways to realize the improvement is the modification of rubbers through chemical reactions, which produce materials with novel properties. In this review, chemical modification reactions of rubbers that contain carbon-carbon double bond units either in their main backbone or as a side group were briefly summarized. The chemical reactions introduce functional groups or functional polymer chains to polymer backbone, which transform a classical rubber to a highly functional material. Especially, we focused on a controlled/"living" radical polymerization techniques, with which a revolutionary broadening of the spectrum of the materials with well defined molecular weight, molecular weight distribution, chain end-functionality and architectures become possible.