• Journal of the Korean Society of Safety
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• v.15 no.4
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• pp.41-46
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• 2000

Silicone rubbers are elastomeric materials and organic copolymers, of which backbone is siloxane with high bonding strength. Silicone rubbers have been used as an power insulator because they are well weather proof, ozone proof and have excellent electric characteristics, thermal stability, cold resistance and low surface energy. Especially, it is known that they have very excellent characteristics at 200[$^{\circ}C$]. For this study, we made silicone rubbers as specimens and measured volume resistivity due to applied voltage and a variation of temperature 25[$^{\circ}C$] to 180[$^{\circ}C$]. Also we measured dielectric loss tangent due to applied voltage at temperature range 25[$^{\circ}C$] to 180[$^{\circ}C$] and frequency range 20[Hz] to 1${\times}10^6$[Hz].

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.779-782
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• 2000

Silicone rubbers are first silicone polymers and has named silicone from existence of Si-O bond similar to Keton. Silicon in organic compound has been called silicone, and linear or network polymers. Silicone rubbers have been used as an power insulator because they are well weather proof, ozone proof and have excellent electric characteristics, thermal stability, cold resistance and low surface energy. Especially, it is known that they have very excellent characteristics at 200[$^{\circ}C$]. For this study, we made silicone rubbers as specimens and we measured dielectric loss tangent due to applied voltage at temperature range 25[$^{\circ}C$] to 180[$^{\circ}C$] and frequency range 20[Hz] to 1${\times}$10$\^$6/[Hz] to examine dielectric properties. We measured dielectric loss tangent to study the insulation performance of silicone rubbers.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.503-506
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• 2004

In this paper we investigated the changes of surface hydrophobic characteristics on silicone rubbers by corona discharge treatment and also investigated the distribution and the behavior of low molecular weight(LMW) silicone fluid which was extracted by solvent-extraction with gel permeation chromatography(GPC). It was shown that contact angle was $110.5^{\circ}$ on initial sample but contact angle was approximately decreased to $10^{\circ}$ after 45 minutes. However the surface hydrophobic characteristic on silicone rubbers which were removed from corona discharge was recovered within 5 hours. It was shown that corona discharge insured the increase of diffusible LMW chains, which could lead to recover the surface hydrophobicity. The surface hydrophobic characteristics on silicone rubbers and the recovery mechanism based on our results were discussed.

• Textile Coloration and Finishing
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• v.35 no.1
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• pp.8-19
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• 2023

Silicone rubber is widely used in most industries due to diverse advantages like heat stability, UV stability, durability, chemical resistance, environment friendliness, inertness and so on. But there is limitation to expand applications due to relatively weak rubber strengths such as tensile strength and tear strength, especially in fabric coating applications. The purpose of this study is to find influence of coating agent on performances of rubber and coated fabrics and their correlation according to different crosslinking densities of silicone rubbers. Addition cure type of silicones were formulated using crosslinked MQ-type silicone resin consisting of M (R₃SiO_1/2) and Q (SiO_4/2) and linear polymers. Raw materials used were; 1) linear vinyl endblocked polymers and vinyl functional MQ resin as main polymers, 2) linear silicone hydride polymers as crosslinkers, 3) platinum catalyst and 4) inhibitor to control curing speed. Rubber specimens were prepared to check mechanical strength using universal testing machine (UTM). Crosslinking density was calculated using Flory-Rhener equation using solvent swelling method. Differential scanning calorimetry (DSC) and scanning electron microscope (SEM-EDS) were used to characterize rubbers. Consequently, it was found that physical properties of silicone rubbers and coated fabrics can be expected by crosslinking density of rubbers. Silicone rubber formulations that contain 20 ~ 30 wt% of vinyl MQ resin showed strongest balanced performances.

• Elastomers and Composites
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• v.32 no.5
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• pp.309-317
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• 1997

Estimation of the dielectric properties of insulating silicone rubbers added reinforcing fillers $(SiO_2,\;0{\sim}140phr)$ are very important to investigate the polymer structure. The characteristies of the dielectric absorption in insulating silicone rubbers were studied in the frequency range from 30Hz to 1MHz at the temperature range from $0{\sim}170^{\circ}C$. In the case of non-filled specimen, the dielectric loss is due to the syloxane which is the main chain of silicone rubber at the low temperature below $50^{\circ}C$ and the frequency at 330Hz, and is due to methyl and vinyl radical over the frequency of 1MHz. It is confirmed that the methyl radical or the vinyl radical becomes thermal oxidation at the high temperature over $100^{\circ}C$ and then the dielectric disperssing owing to the carboxyl radical Is appeared. In the case of filled specimen, the dielectric constant is in creased with the additives of reinforcing fillers due to the effect of interfacial polarization explained by MWS(Maxwell-Wagner-Sillars)'s law. The dielectric loss is decreased by the disturbance of reinforcing fillers that is permeated between networks.

• Proceedings of the KIEE Conference
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• 1996.07c
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• pp.1541-1543
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• 1996

This paper describes the results of characteristics on the tracking resistance, hydrophobicity and dielectric properties of silicone rubbers used for outdoor insulation with ozone ageing. The tracking and ozone ageing tests for this purpose ware made in according to IEC 587 and ASTM D 1149, respectively. Additionally, we investigated the surface structure of the silicone rubbers with FT-IR and SEM. From the test results, it is proven that the higher the degree of ozon ageing, the worse tracking characteristics.

• Elastomers and Composites
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• v.28 no.3
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• pp.198-204
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• 1993

The dielectric properties of silicone rubbers are very important to investigate the polymer structure. The characteristics of the dielectric absorption in silicone rubbers were studied in the frequency range of 30Hz to $1{\times}10^6Hz$ at the temperature range of $30^{\circ}C$ through $170^{\circ}C$. As the results of the study, dielectric constant, tangent 5 were measured $2.8{\times}4.5,\;0.007{\times}0.08$.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1216-1217
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• 2008

A description is given of impregnated silicone rubber used in accessories for application on outdoor termination (EB-A). We examines the effects of swelling and mechanical/electrical characteristics for impregnated silicone rubber to develop slip on type sleeve of silicone material. There are semi-conductive silicone rubber and insulation silicone rubber. This examination is monitored as a function of the viscosity and temperature of oil during 30hr. We measure elongation at breakdown and AC breakdown strength and volume resistivities of the oil-impregnated silicone rubbers. The measured values are compared to initial value as function of stress relief cone.

• Elastomers and Composites
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• v.44 no.1
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• pp.2-12
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• 2009

• Elastomers and Composites
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• v.50 no.1
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• pp.55-61
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• 2015

Manufacturing process of OLED contains adsorption-desorption process of glass substrate. There are several adsorption methods of glass substrate such as atmospheric pressure, vacuum and electrostatic adsorption. However, these methods are very complex to connect system. Therefore, the adsorption method using silicone rubber based sticking chuck was proposed in this study. Three types of silicone rubbers having 0, 19.3 and 32.2 wt% of fluorine were used and their mechanical properties, surface energies and adsorption properties were examined. According to the results ${\sigma}_{300}$ and hardness increased with increasing fluorine contents, but elongation was decreased. Also, fluorosilicone rubber containing 32.2 wt% of fluorine showed the lowest surface tension, among three types of rubber and resulted in the highest initial tack with glass substrate. After the adsorption-desorption test of 300,000 cycles was performed, the adsorption force of S-1 (silicone rubber) decreased largely from 2.34 to 0.73 MPa. However, the S-3 (fluorosilicone rubber having 32.2 wt%. of fluorine) decreased only from 3.15 to 2.24 MPa. From this study, we obtained the valuable equations related to long term durability of silicone based sticking chuck. Finally the transfer of silicone rubber to glass substrate with the adsorption-desorption process was not occurred and this phenomenon was examined by UV-Visible spectroscopy.