• Journal of Adhesion and Interface
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• v.7 no.4
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• pp.39-44
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• 2006

A new kind of silicone-epoxy composite is reported in this research. The silicone-epoxy resin was synthesized by the hydrosilylation of tetramethycyclotetrasiloxane and 4-vinyl-1-cyclohexene 1,2-epoxy with a high reaction yield. It was found that the obtained silicone-epoxy resin shows a high reactive activity to the aluminum complex-silanol catalyst. The resin could be cured under the catalysis of $(Al(acac)_3/Ph_2Si(OH)_2$ at a concentration below 0.1 wt% to give a hard cured resin showing excellent optical clarity, UV resistance and thermal stability. It was also found that the Si-H groups facilitated the curing reaction and the silicone-epoxy resin bearing Si-H group could be cured effectively even if $Ph_2Si(OH)_2h$ was absent. Moreover, the UV resistance and thermal stability were improved significantly by the introduction of Si-H groups. This is possibly due to the reductive property of Si-H groups which can annihilate radical and peroxide effectively. This kind of silicone-containing epoxy composite might have very promising applications as optical resin, optical adhesive and encapsulation materials for electronic devices.

• Transactions on Electrical and Electronic Materials
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• v.17 no.3
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• pp.155-158
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• 2016

The effect of microsilica content modified with silicone-modified epoxy on electrical and mechanical properties of cycloaliphatic epoxy/microsilica system was investigated. The cycloaliphatic epoxy resin was diglycidyl 1,2-cyclohexanedicarboxylate and curing agent was an anhydride. Surface of microsilica was modified with silicone-modified epoxy. Electrical breakdown strength, the most important property for electrical insulation materials was tested. Tensile and flexural tests were also performed using universal testing machine (UTM). The microcomposite with 60 wt% microsilica shows maximum values in electrical breakdown strength.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.771-774
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• 2000

Recently, complex insulation method is used in insulation system for underground power delivery devices. Considering the interfaces which affect stability of insulation system, By modeling interface between Epoxy and Rubber, AC interfacial breakdown properties with variation of many conditions to influence on electrical properties were investigated. In this paper, toughened Epoxy and Silicone rubber were used for materials to make interface .

• Journal of the Korean Applied Science and Technology
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• v.27 no.1
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• pp.87-92
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• 2010

Silicone surfactants are widely used in many industrial area because of its thermal stability and lower foaming property. But it has limitation to expand the application because of migration and bubble generation issues when it is mixed with organic surfactant. In this study, epoxy functionalized fluoro-silicone surfactant, perfluoro glycidoxypropyl polyether siloxane(PFGES), was synthesized using hydrosilylation reaction among perfluoro methyl hydrogen siloxane, allyl glycidyl ether, and allyl ployether in order to get lower surface tension, better thermal stability than conventional silicone surfactant, and reactivity with anhydride function.

• Clean Technology
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• v.23 no.4
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• pp.378-387
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• 2017

To obtain epoxy resin with permanently attached flame-retardant groups, phosphorus compound containing di-hydroxyl group [10-(2,5-dihydroxyphenyl)-9,10-dihydro-9-oxa-10-phospha phenanthrene-10-oxide, DOPO-HQ] and silicone compound containing di-hydroxyl group (polydimethylsiloxane, hydroxyl terminated, PDMS) were reacted with uncured epoxy prepolymer (diglycidyl ether of bisphenol A, DGEBA) and then cured using 4,4-diaminodiphenylmethane (DDM) as a crosslinking agent. The properties of the resulting epoxy materials were characterized using Fourier transform infrared (FTIR) spectrometer, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), limiting oxygen index (LOI) test/vertical burning test (UL 94-V test), tensile properties test and impact test. This study examined the effect of phosphorus/silicone compound contents on the thermal/mechanical properties and flame retardancy of cured epoxy resins containing phosphorus and silicone compounds. It was found that the thermal/mechanical properties of epoxy resins containing phosphorus and silicone components were higher than those of simple epoxy resin. The flame-retardancy (LOI: 29.9 ~ 31.8% and UL 94-V: V-0) of all samples containing phosphorus compound and phosphrous compound/silicone compound was found to be passed the flame-retardant requirements (LOI: > 30%, UL 94-V: V-0) of LOI and vertical burning tests. However, the flame-retardancy (LOI: 21.4% and UL 94-V: no rating) of simple epoxy resin was found to be failed the flame-retardant requirements.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07a
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• pp.431-434
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• 2002

This paper reports on the evaluation of weathering resistance, tracking test and salt-fog of various kinds of cycloaliphatic epoxy systems. It was found that UV irradiation induced the loss of hydrophobic level due to the chain scission attack at the surface. It could be seen that samples containing an UV absorbent/antioxidant and a silicone oil additive knave a good performance in weathering ageing, whereas ATH filled ones have high resistance against tracking failure than others. Under salt-fog test, specimens mixed with silicone oil could suppress leakage current development. It was thought that silicone oil mixed into cycloaliphatic epoxy system could lead to lower the surface energy and to retain hydrophobic properties for a long time, which are desirable for outdoor performances.

• Transactions on Electrical and Electronic Materials
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• v.18 no.4
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• pp.203-206
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• 2017

The effect of the content of microsilica and nanosilica continuously modified with hydroxy silane and epoxy-modified silicone in cycloaliphatic epoxy/microsilica/nanosilica composites (EMNCs) on the mechanical and water repellent properties was evaluated. Surface-modified micro- and nanosilica was well-mixed with a cycloaliphatic epoxy resin in the presence of polyester-modified polydimethylsiloxane (PEM-PDMS) as a dispersing agent using an ultrasonicator. Tensile and flexural tests were carried out using a universal testing machine (UTM). The water repellent property was evaluated by contact angle measurements of water on the composite surface. Tensile strength of the composite could be enhanced by 32.2% up to 91.4 MPa, and the flexural strength was raised to 122.0 MPa, which is 38.8% higher than that of neat epoxy. The contact angle of water on the composite was as high as $104.1^{\circ}$.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.12
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• pp.1079-1084
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• 2002

Because complex insulation method is used in EHV(extra high voltage) insulation systems, macro Interfaces between two different bulk materials which affect the stability of insulation system exist inevitably. Interface between toughened epoxy and silicone rubber was selected as a interface in EHV insulation systems and tested AC interfacial breakdown properties with variation of many conditions to influence on electrical Properties, such as interfacial pressure, roughness and oil. Specimen was designed to reduce the effect of charge transport from electrode in the process of breakdown and to have the tangential electrical potential with the direction of the interface between epoxy and silicone rubber by using FEM(finite elements method). It could control the interfacial pressure, roughness and viscosity of oil. From the result of this study, it was shown that the interfacial breakdown voltage is improved by increasing interfacial Pressure and oil. In particular, the dielectric strength saturates at certain interracial Pressure level. The decreasing ratio of the interfacial breakdown voltage in non-oiled specimen was increased by the temperature rising, while oiled specimen was not affected by temperature.

• Magazine of the Korean Society of Agricultural Engineers
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• v.25 no.2
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• pp.67-75
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• 1983

The objectives of this paper were to measure the bond strengths of reinforced concrete in which the steel rods were coated with five different kinds of anticorrosion paints, and to compare their prevention effects in salt water. The paints used in the study were epoxy resin I . II . III, Z.R. P., and silicone resin, which were applied at rates recommended by the manufacturers. The bond strengths were measured on the 7-, 14-, and 28-th days after molding. Corrosion conditions of coated steel plate under fresh water, seawater, 10 % salt water, and 20% salt water, were inspected every month during four months test peoriods, respectively. The results obtained from tests are summarized as follows: 1. Paint-coating may reduce the bond strengths of reinforced concrete. Silicone resin paint showed some 20% reduction in the strength compared to those without the paint. However, the other paints seemed not to significantly affect the strength. 2. Picture analyses showed that epoxy resin I and II significantly prevented corrosion steel plates in seawater. Epoxy resin I and silicone resin coating did not do a good job in corrosion prevention. Z.R. P. paint was found to be moderate as preventive coating paint. 3. Varying soluble salt contents had little effects on the corrosion prevention of tested paints. 4. Epoxy resin I and II were found to be appropriate as a coating material to prevent the corrosion of steel rods in seawater. Z.R.P. may also be used for the purpose.

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.3
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• pp.383-394
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• 1999

The indirect technique for making cast restoration requires that dies be as accurate and durable as possible. Currently, stone is the most commonly used material for die. However, it has some problems such as the weakness in its strength and low abrasion resistance. Recently, epoxy resin die systems have become available. The purpose of this study was to examine two commercially available resin die systems and evaluate some characteristics for their clinical performance. This study evaluated the dimensional accuracy of epoxy resins and their wettability with impression materials. In this study, the first experiment was about dimensional accuracy of different die materials. The master model was made of stainless steel. 10 models were made of two epoxy resins (Die-epoxy, Tri-epoxy) and a die stone (Fujirock) each. Occlusal diameter (Dimension I), occluso-gingival height (Dimension II), and interabutment distance (Dimension III) were measured in each model. Next, the contact angles of die materials with impression materials were observed. The blocks were made of polyether, hydrophilic additional silicone, polysulfide impression materials. By drop-ping the same amount (0.05ml) of Tri-epoxy, Die-epoxy, and die stone on the blocks, 10 samples of each die material were made. After setting of materials, the contact angles were measured. The results of this study were as follows. 1. The expansion of stone die and the shrinkage of resin dies in occlusal diameter were observed, and stone and Tri-epoxy were expanded and Die-epoxy was shrinked in occluso-gingival height. There was little change among materials in interabutment distance (p<0.05). 2. In comparison with the master model Tri-epoxy had the least variation in measurement of the three die systems examined. Die-epoxy was next, and die stone showed the greatest variation. 3. The compatibility of die stone for polyether, hydrophilic additional silicone, polysulfide decreased in order, wherease epoxy materials had the decreased compatibility for polyether and polysulnde, hydrophilic additional silicone in order. It was not statistically different between polyether and polysulfide (p<0.05). 4. The contact angles of Tri-epoxy, Die-epoxy, die stone were getting bigger in order.