• The Journal of Korean Academy of Prosthodontics
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• v.38 no.5
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• pp.650-658
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• 2000

This study was investigated to compare the bond strength of polysulfide adhesive between tray resin and border molding materials and to evaluate the effect of saliva contamination on them. We made the 135 resin tray secimens with a dimension of $1{\times}1{\times}1cm$ and divided them into 3 groups by the materials 1) Quicky group, 2) Compound group, and 3) Impregum group Each group was subdivided by saliva contimination. Group S1 : applied adhesive without saliva contamination Group S2 : applied adhesive after drying 15seconds after saliva contamination Group S3 : applied adhesive no after saliva contamination. Tensile tests were performed with a Universal Load testing machine. Results showed Impregum group significantly higher bond strength than Quicky group, but there was no significant difference in adhesive bond strength between Compound group and Quicky group in experimental group by materials In experimental group by saliva contamination, S1 group is significantly higher bond strength than S2 group and S2 group is significantly higher bond strength than S3 group in Quicky group and S1, S2 group is significantly higher bond strength than S3 group in Compound group and Impregum group. Impression compound and Impregum F which are usually used as an individual tray border mold-ing material can be said to be satisfied in adhesive bond strength to polysulfide impression materials. After try-in and clinical adjustment are performed, a custom tray should be properly rinsed and air dried before tray adhesive was placed.

• The Journal of Korean Academy of Prosthodontics
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• v.34 no.4
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• pp.850-868
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• 1996

The accuracy and dimensional stability of impression materials are one of the most important factors for successful prosthodontic treatment. The purpose of this study was to evaluate the accuracy of several dental elastomeric impression materials used widely and clinically : Impregum-$F^{(R)},\;Permlastic^{(R)},\;Silascon^{(R)},\;Perfect^{(R)},\;Xantopren^{(R)}$. There have been many studies to evaluate the accuracy of impression materials. But it has not been decided yet, which method was most suitable for the evaluation of the accuracy. In this study, two resin teeth, #15 & 25, were prepared with rounded shoulder margin and 90 degree cavosurface angle. For the polysulfide rubber and polyether, the custom tray was made at least 24 hours prior to impression taking. For the silicone rubber materials, putty/wash impression technique was applied in taking impressions. Marginal openings of the castings on the master dies and prepared resin teeth were measured under stereomicroscope. The results were statistically analyzed and compared between tested impression materials. The results were as follows ; 1. In the overall accuracy of impression materials, polyether was the most accurate one, followed by polysulfide, additional silicone and condensation silicone. 2. On the first model pouring, condensation silicone had the largest discrepancies and there was significant difference compared to the other impression materials. 3. Polysulfide had the least discrepancies in the first model pouring, but showed larger discrepancies in the immediate second pouring than the first pouring. 4. On the immediate second pouring, the discrepancy of polyether was shown to be the smallest, while the largest one was additional silicone. 5. Polyether and polysulfide rubber using custom impression trays showed superior accuracy to silicone rubber, putty/wash impression technique.

• Journal of the Korean Electrochemical Society
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• v.24 no.3
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• pp.42-51
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• 2021

Dissociation into Lithium-polysulfide electrolyte due to repeated cycles during the Lithium/Sulfur battery reaction is a major problem of reduced battery lifespan. We searched for a porous carbon with a large specific surface area that infiltrated S to prevent liquid Lithium-polysulfide from being dissolved in electrolyte, induce adsorption of Lithium-polysulfide, and further increase conductivity. In order to obtain porous carbon spheres with a large specific surface area, the carbon spheres of 1939 m²/g were raised to 2200 m²/g through additional KOH treatment. In addition, through heat treatment with S, a carbon sulfur compound containing 75 wt% of S was fabricate and material analysis was conducted on the possibility of using the cathode material. The electrochemical characteristics of the Reference (622; sulfur: 60%, conductive material: 20%, binder: 20%) pouch cell and the pouch cell made using 75wt% of carbon sulfur compound were analyzed. 75wt% of carbon sulfur pouch cell showed a 20% increase in lifespan and 10% improvement in C-rate compared to the Reference pouch cell after 50 cycles.

• The Journal of Korean Academy of Prosthodontics
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• v.27 no.2
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• pp.249-259
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• 1989

Dental impression materials often become contaminated with patients' saliva and blood which creates the potential for cross-infection. It was the purpose of this study to investigate the effects of disinfection of three different rubber impression materials with four different disinfecting solutions. Polysulfide, vinyl polysiloxane and polyether impression materials were mixed according to the manufacturer's directions and samples were formed on a stainless steel model. On removal from the standard model, impressions were immersed in a disinfectant (acid-potentiated glutaraldehyde, phenollic compound, chlorine compound, iodophor) at room tempera tures for ten minutes. After disinfection, the distance between reference points(linear dimension) was measured using the non-contact automatic cordinate measuring projector(MZ-1, Nikon). Through statistical analyses on the data from this study,. the following conclusions were obtained. 1. Polysulfide, vinyl polysiloxane impressions were disinfected without dimensional change.(p>0.05) 2. Polyether impressions which were immersed in acid-potentiated glutaraldehyde were statistically different from control group.(p<0.05) But the amount of shrinkage(0.04%) would not be clinically significant. 3. By immersion of polysulfide, vinyl polysiloxane, polyether impressions in Banicide, Biocide, Multicide plus, sodium hypochlorite for ten minutes, clinically accurate impressions were obtained without dimensional change.

• 대한치과보철학회:학술대회논문집
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• 1997.11a
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• pp.54-54
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• 1997

• Bulletin of the Korean Chemical Society
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• v.19 no.11
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• pp.1262-1265
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• 1998

• Journal of the Korean Electrochemical Society
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• v.14 no.2
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• pp.104-109
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• 2011

We fabricated CdSe-sensitized photoelectrochemical solar cell by depositing CdSe nanoparticles on nanoporous $TiO_2$ (np-$TiO_2$) via spray pyrolysis deposition method. By adjusting the amount of CdSe-sensitizer deposited on np-$TiO_2$, we can fabricate an efficient CdSe-sensitized solar cell (${\eta}$ = 3.0% under 1 sun irradiation) in polysulfide liquid electrolyte.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4D
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• pp.587-592
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• 2006

The joint sealants used in the airside should resist the high temperature of the jet blast and the jet fuel oil spilled when the aircraft is maintained and filled. The material of joint sealant for the airside should be different from that for the road due to these characteristics. Three different kinds of the joint sealant materials were tested in this paper. The materials include the polysulfide, the polyurethane and the silicon. The test results show that the physical properties and the performance of the polysulfide show the high resistance to the jet blast and the jet fuel oil. When the characteristics of the airside considered, the polysulfide may apply in the both of the runway and the apron area, the polyuretane can be applied the taxiway. The use of the silicon sealant is not recommended for the airside.

• International Journal of Highway Engineering
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• v.13 no.2
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• pp.159-166
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• 2011

This research was performed to evaluate physical properties of polysulfide epoxy overlay material for bridge deck as part of a review for possibility of domestic application of polymer concrete for bridge deck pavement. In order to evaluate strength characteristics, compressive strength, flexural strength and bond strength were tested, and, for durability characteristics, chloride ion penetration resistance and freeze/thaw resistance were tested along with ultraviolet rays impact evaluation. The tests showed that the results met the criteria suggested by the American Concrete Institute in terms of compressive strength, flexural strength and bond strength. However, in terms of the strengths measured at various test temperatures, it was found that the epoxy material was highly dependent on temperature, and, therefore, this should be considered at the time of domestic application of the epoxy material later. Deflection characteristics was checked through flexural strength test and it was found that bridge deck pavement using the epoxy material was excellent compared to bridge deck pavement using asphalt. Furthermore, the results of chloride ion penetration resistance test and freeze/thaw resistance test were also excellent. In the evaluation of ultraviolet rays impact on epoxy slurry mixture, reduction of strain was noticed with increased strength, but the deflection characteristics after exposure to ultraviolet rays was better than the existing acryl polymer concrete. Therefore, it is concluded from the research that the polysulfide epoxy overlay material has the physical properties that are appropriate to pavement of bridge deck.

• Journal of Dental Rehabilitation and Applied Science
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• v.25 no.1
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• pp.31-40
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• 2009

The rheologic properties of elastic impression materials is a very important role as taking high accuracy impression. But, the studies that are focused on the rheologic properties of Korean elastic impression materials are not sufficient. The purpose of this study is to help clinical high accuracy impression taking by testing rheologic properties of elastic impression material that is made by Korea and other countries. Six type III elastic impression materials are tested. Subjects are 2 Korean polyvinylsiloxane(PVS), 2 imported PVS, 1 polyether, and 1 polysulfide. HAAKE RheoStress $1^{(R)}$(Thermo Electron Co. Germany)is used in measuring. HAAKE RheoStress $1^{(R)}$ is plate to plate type rheometer. All subjects is tested 3 times and measuring time is 900 seconds. We measured G′ and loss tangent after mixing. All elastic impression materials had a sigmoid shape on increasing G′ by time and decreasing loss tangent after setting, maximum G' is appeared highest in polyether, and lowest in polysulfide. Initial loss tangent is highest in polyether, and is lowest in Koreans PVS. Significant difference is showed in initial loss tangent between Korean PVS and imported PVS.