• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.29-29
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• 2010

Engineering plastics have excellent electrical properties, mechanical strength and various characteristic which include chemical resistance, environmental resistance, weatherability at a wide temperature range. It has good characteristic(light weight, good productivity) as compare with epoxy or porcelain insulators. However, engineering plastics not suited to outdoor insulator because it isn't hydrophobic. Therefore, to over come these critical problems, we improve the surface insulation characteristics of engineering plastic by coating micro-, nano- size inorganic fillers added to RTV-SIR(Room temperature vulcanized-silicone rubber) at this plastic surface. The effect is analyzed through salt-fog test, tracking test. In conclusion, the engineering plastic coated RTV with micro-$Al_2O_3$20[phr], nano-Al(OH)3 1 ~ 3[phr] improved much better than the others.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.03b
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• pp.29-29
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• 2010

Surface contamination and leakage current have caused operating problems. A flashover in a substation may result in destruction of an insulator or many others electrical equipment. Engineering plastics have good characteristic (light weight, good productivity and little of void) as compare with epoxy or porcelain insulators. Outdoor insulator must have resistance to contamination. However, it isn't suited to outdoor insulator because it is not hydrophobic. RTV(Room temperature vulcanizing) has a good property of hydrophobic and micro-filler. nano-filler have characteristics of obstructing exothermic reaction. In order to reduce the incidence of insulator flashover and damage, the silicon rubber contained with micro, nano-filler coating on surface of engineering plastics. In this paper, it compares tracking resistance, leakage current of the engineering plastic coated RTV with that of non-coated engineering plastic. And filled-composites performed much better than non-filled composites.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.688-693
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• 2003

The PSP technique has been used to measure pressure distribution on a model surface quantitatively. The objective of this study is to develop PSP technique which can be applied to low-speed flows. Four different PSP formulations including two porphyrins (PtOEP and PtTFPP) and two polymers (Poly(TMSP) and RTV-118) were tested and the performance of each combination was checked. In the static calibration, the luminescent intensity of the PSP coatings was measured from 0kPa to 11kPa with 0.5, 1, 2kPa increments. Among 4 PSP formulations tested, the combination of PtOEP and RTV-118 shows the best performance. The PSP technique was applied to an oblique impinging jet to measure the pressure field distribution on the impinging plate.

• The Journal of Advanced Prosthodontics
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• v.11 no.6
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• pp.305-312
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• 2019

PURPOSE. The purpose of this study was to compare computer-aided design/computer-aided manufacturing (CAD/CAM) abutment and prefabricated abutment in Morse taper internal connection type implants after cyclic loading. MATERIALS AND METHODS. The study was conducted with internal type implants of two different manufacturers (Group Os, De). Fourteen assemblies were prepared for each manufacturer group and divided into 2 groups (n=7): prefabricated abutments (Os-P, De-P) and CAD/CAM abutments (Os-C, De-C). The amount of axial displacement and the removal torque values (RTVs) were measured before and after cyclic loading (10⁶ cycles, 3 Hz with 150 N), and the tensile removal force to dislodge the abutments was measured after cyclic loading. A repeated measures ANOVA and a pattern analysis based on the logarithmic regression model were conducted to evaluate the effect of cyclic loading on the axial displacement. The Wilcoxon signed-rank test and the Mann-Whitney test was conducted for comparison of RTV reduction% and tensile removal forces. RESULTS. There was no significant difference between CAD/CAM abutments and prefabricated abutments in axial displacement and tensile removal force; however, significantly greater RTV reduction% after cyclic loading was observed in CAD/CAM abutments. The correlation among the axial displacement, the RTV, and the tensile removal force was not significant. CONCLUSION. The use of CAD/CAM abutment did not significantly affect the amount of axial displacement and tensile removal force, but presented a significantly greater removal torque reduction% than prefabricated abutments. The connection stability due to the friction at the abutment-implant interface of CAD/CAM abutments may not be different from prefabricated abutment.

• Journal of the Korean Chemical Society
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• v.48 no.3
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• pp.266-272
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• 2004

We developed a miniaturized solid-state carbonate ion-selective electrode (carbonate ISE) based on one-component room temperature vulcanizing type silicone rubber 730 (730 RTV) without adding plasticizer to the matrix. The optimized carbonate ion selective membrane is prepared with 85.8 wt% of 730 RTV, 11.1 wt% of trifluoroacetyl-p-decylbenzene (TFADB), and 3.1 wt% of tridodecyl-methylammonium chloride (TDMACl). This carbonate ISE exhibited excellent potentiometric properties (i.e., slope: 26.3 mV/dec; selectivity: $logKT^{pot}_{CO_{2},Cl^-}$= -4.00 and $logKT^{pot}_{TCO_{2},Sal^-}$=1.69); and detection limit for $TCO_2:\;4.0{\times}10^{-4}M$). In addition, the early potentiometric properties of the solid-state sensor with optimized membrane composition were not deteriorated for more than 60 days.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.259-259
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• 2009

Surface contamination and leakage current have caused operating problems. A flashover in a substation may result in destruction of an insulator or many others electrical equipment. Engineering plastics have good characteristic (light weight, good productivity and little of void) as compare with epoxy or porcelain insulators. Outdoor insulator must have resistance to contamination. However, they are not suited to outdoor insulator by reason of being not good hydrophobic. RTV has a good property of hydrophobic and ATH has characteristic obstructing exothermic reaction. In order to reduce the incidence of insulator flashover and damage, the silicon rubber contained nano size ATH coat on surface of engineering plastics. In this paper, it compares resistance tracking of the engineering plastic coated RTV with that of non-coated engineering plastic and ATH filled composites performed much better than non-filled composites.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.9
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• pp.3895-3899
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• 2012

In this study, the start-type molded material, silicone resin(RTV-3040) was used to develop a mold that is utilized for embossing pattern. After selecting a required pattern using the commercial package (Freeform), we examined whether this is applicable to components creating projective embossed side on the surface. We responded to products that require corrosive pattern, such as aluminum mold, by making the starting type when small amounts of components are developing. However, the development of silicone mold that is applied to corrosive pattern showed the possible reduction in time and cost.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1449_1450
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• 2009

Surface contamination and leakage current have caused operating problems. A flashover in a substation may result in destruction of an insulator or many others electrical equipment. Engineering plastics have good characteristic (light weight, good productivity and little of void) as compare with epoxy or porcelain insulators. Outdoor insulator must have resistance to contamination. However, they are not suited to outdoor insulator by reason of being not good hydrophobic. RTV has a good property of hydrophobic and ATH has characteristic obstructing exothermic reaction. In order to reduce the incidence of insulator flashover and damage, the silicon rubber contained nano size ATH coat on surface of engineering plastics. In this paper, it compares resistance tracking of the engineering plastic coated RTV with that of non-coated engineering plastic and ATH filled composites performed much better than non-filled composites.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.3
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• pp.75-83
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• 2001

RIM(Reaction Injection Molding) is a widely used method to manufacture middle-large size outfit-part for a prototype car. The main advantage of RIM is the capability of manufacturing a small number of prototype parts with less cost and lead time than injection molding which is the most popular method to manufacture plastic parts. Generally, epoxy resin and RTV(Room Temperature Vulcanization) silicon are used as mold materials for RIM, and the selection of mold materials is usually depended upon the industrial environment of manufactures and it decides overall mold making process and part quality. This paper suggests a new mold making process by consolidating the advantages of epoxy resin and RTV silicon based RIM mold to enhance the parts quality while reducing the manufacturing cost and time and shows the competitiveness of the suggested process compared with conventional methods.

• Composites Research
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• v.17 no.5
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• pp.61-67
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• 2004

This paper reports the electrical conductivity and the stress-strain behavior of silver particle-filled silicone composite pastes for electromagnetic interference (EMI) shielding gasket materials. The percolation threshold (critical concentration) of the composite paste obtained by incorporating irregular sphere-shaped silver particles and room temperature vulcanizing (RTV) silicone resin was determined from the electrical conductivity result. At about 28 vol% Beading of untreated silver particles, the percolation phenomenon occurred and at this critical concentration, the volumetric resistivity, the tensile strength, and the elongation of the pastes were investigated. This work also suggests that the stress-strain characteristics of a composite paste filled with metal particles above the percolation threshold may be effectively improved by properly selecting a coupling agent.