• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.565-569
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• 1999

In these days, the silicone insulators have been increasingly studied and applied for outdoor insulators because it has superior characteristics than porcelain and glass insulators, which have been used for outdoor insulators. First of all, 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 contamination and wet conditions. This is because of the presence of low molecular weight mobile fluid in the silicone rubber which diffuses to the surface and to above the contamination layer. But, the leakage current and some surface discharge occurs on surface of the composite polymeric insulation materials when the insulator is used for a long time with severe contaminative condition and it can lead the contamination flashover. So the leakage current and the discharge current are important to estimate the condition of the silicone rubber surface. In this paper, the average leakage current, the relation of surface discharge current and phase angle were study to investigate electrical conduction of silicone rubber surface with the salt fog condition.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1367-1369
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• 1994

Recently composite insulators have been In the spotlight because they have many good characteristics as a outdoor insulator for high voltage. The long term properties in composite insulator depend on shed materials. Silicone rubber out of some candidates of shed material has been obtaining good credit from the long term test in field.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.50 no.10
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• pp.479-488
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• 2001

The effects of accelerated Ultraviolet (UV) radiation on High temperature vulcanized (HTV), Room temperature vulcanized (RTV) silicone rubber and two types of ethylene propylene diene terpolymer (EPDM) used for composite insulator were inverstigated by hydrophobicity class (HC), surface voltage decay after corona charging, SEM-EDS, FTIR and XPS. The contact angle in two kinds of silicone rubber was scarcely change, but EPDM occurred to the loss of hydrophobicity followed by surface cracking and chalking. The surface voltage decay on UV-treated silicone rubber and EPDM showed a different decay trend with UV treatment. EDS and XPS analysis indicated that the oxygen content increased with UV treatment time in all samples. For silicone rubber, the oxidized groups of inorganic silica-like structure increased with UV treatment time. The oxidized carbon of C=0, O=C-O in EPDM increased. These oxidized surface for each material had different electrostatic characteristics, so deposited charges were expected to have different impacts on their surface hydrophobicity. The degradation mechanism based on our results was discussed.

• Steel and Composite Structures
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• v.44 no.5
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• pp.741-752
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• 2022

Earlier works have shown that excessive shear stiffness at the steel-concrete interface causes a non-uniform distribution of shear force in composite structures. When the shear studs are wrapped at the fixed end with flexible materials with a low elastic modulus, the shear stiffness at the interface is reduced. The objective of this study was to investigate the effect of silicone rubber-sleeve mounted on shear studs on the shear stiffness of steel-concrete composite structures. Eighteen push-out tests were conducted to investigate the mechanical behavior of silicone rubber-sleeved shear stud groups (SRS-SSG). The dimension and arrangement of silicon rubber-sleeves (SRS) were taken into consideration. Test results showed that the shear strength of SRS-SSG was higher than that of a shear stud group (SSG), without SRS. For SRS-SSG with SRS heights of 50 mm, 100 mm, 150 mm, the shear strengths were improved by 13%, 20% and 9%, respectively, compared to the SSG alone. The shear strengths of SRS-SSG with the SRS thickness of 2 mm and 4 mm were almost the same. The shear stiffness of the SRS-SSG specimens with SRS heights of 50 mm, 100 mm and 150 mm were 77%, 67% and 66% of the SSG specimens, respectively. Test results of specimens SSG-1 and predicted values based on the three design specifications were compared. The nominal single stud shear strength of SSG-1 specimens was closest to that calculated by the Chinese Code for Design of Steel Structures (GB50017-2017). An equation is proposed to consider the effects of SRS for GB50017-2017, and the predicted values based on the proposed equation agree well with the tested results of SRS-SSG.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.04a
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• pp.29-34
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• 2004

Generally, a silicone rubber and a chloride polyethylene(CPE) have been used for the development of high-performance composite EM(ElectroMagnetic) wave absorbers. In this study, the EM wave absorption abilities for natural lacquer which is newly suggested in this study as a binder for composite EM wave absorbers were investigated to develop an improved EM wave absorbers. In addition, MnZn ferrite composite EM wave absorbers mixed with the natural lacquer were prepared and their absorption ability was also investigated. MnZn ferrite composite EM wave absorbers which employs the natural lacquer as a binder showed an improved EM wave absorption characteristics in comparison with the conventional binder such as a silicone rubber and a chloride polyethylene(CPE). The matching frequency and the absorption ability of EM wave absorbers mixed with natural lacquer can be controled the change of the thickness of them.

• 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.

• Journal of Navigation and Port Research
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• v.28 no.10 s.96
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• pp.861-867
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• 2004

Generally, a silicone rubber and a chloride polyethylene(CPE) have been used as a binder for high-performance composite EM( Electromagnetic) wave absorbers. In this study, the EM wave absorption abilities for natural lacquer which is newly suggested as a binder were investigated MnZn ferrite composite EM wave absorbers mixed with the natural lacquer were prepared and their absorption ability was also investigated. The prepared MnZn ferrite composite EM wave absorbers mixed with natural lacquer showed an improved EM wave absorption characteristics compared with MnZn ferrite EM wave absorbers mixed with the conventional binders. such as a silicone rubber and a chloride polyethylene(CPE). The matching frequency and the absorption ability of EM wave absorbers varied with the thickness of them.

• Elastomers and Composites
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• v.46 no.2
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• pp.164-170
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• 2011

In this study, silicone rubber filled with environmentally-friendly perlite was prepared by mechanical mixing in order to improve thermal properties, such as heat and fire resistances. We found that the properties of silicone rubber composites depended on perlite concentration by various characterization methods. Thermogravimetric analysis(TGA) indicated that the initial degradation temperature of silicone/perlite composite was higher than that of pristine silicone rubber. The gas torch test showed that the opposite side temperature of composite materials was remarkably low as compared to that of pristine silicone rubber. In addition, the composites containing 5 wt% and 10 wt% of perlite showed remarkable thermal stability at elevated temperatures according to the results of both fireproof furnace tests under the RABT condition and carbonization furnace tests. The images from a scanning electron microscope(SEM) showed the degree of dispersion of perlite in silicone rubber. Finally, it was confirmed that limited oxygen index(LOI) was increased with perlite concentration.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1621-1623
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• 1999

Recently, high voltage outdoor ploymer insulators have been widely used commercially owing to their excellent electrical and mechanical properties, superior comtamination flashover performance, light weight, easy installation or handing, no maintenance during service, competitive price and so on. compared to porcelaain and glass insulators. For instance, silicone rubber(SR) for polymeric insulators specially has much superior insulating and anti-pollution performance due to its specific hydrophobicity even in severe contaminated environments. We have investigated surface discharge current characteristics of silicone rubbers(SR) for HV outdoor composite insulation specimen under accelerated aging codition using a computer measuring system. The relations of average leakage current and surface discharge current repetition rates and discharge current amplitude, the distribution of discharge current amplitude were studied to investigate electrical conduction of silicone rubber surface with the salt fog condition.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1578-1580
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• 1999

Silicone rubber is being used for the housing material of outdoor high voltage insulators such as composite insulator, bushing, surge arrestor and cable terminator because of good tracking and erosion resistance, good hydrophobicity and recovery of hydrophobicity, and chemical stability. In this paper, tracking and erosion resistance of silicone rubber having fluids and different ATH contents were examined. Fluids were selected under the consideration of their molecular weight and chemical structure, expecting the high migration rate, the good pollutant encapsulation, and the long period with good hydrophobicity. Good tracking and erosion resistance and arc resistance have been achieved for the silicone rubber above ATH content 130 phr.