• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.47-49
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• 2012

Under this study, the characteristics of concrete intensity condition following the curing method under the extremely low temperature environment have been contemplated, and as a result, in the event of insulation + heat cable curing, the intensity and accumulated temperature accomplishment period is required for two times of requiring initial frost damage prevention than the case of heating + heat insulation curing method due to the insufficient calories supplied in general.

• Textile Coloration and Finishing
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• v.11 no.6
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• pp.7-17
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• 1999

Aminophosphazene derivatives were prepared from hexachlorocyclotriphosphazene and used for the curing agents of epoxy resins. The effect of the curing agent on the dynamic viscoelastic properties, flame proofing, and heat resistance of the cured epoxy resins were investigated and compared with those for the epoxy resins cured with aliphatic and aromatic amines. The epoxy resin cured by 1,1-diamino-3,3,5,5-tetrachlorocyclotriphosphazene showed the highest storage modulus and glass transition temperature when cured at 19$0^{\circ}C$ for 6 hours. The epoxy resins cured with phosphazene derivatives showed superior flame proofing to those with aliphatic amine and aromatic amine. Particularly it is an effective curing agent for epoxy resins to enhance the storage modulus, flame proofing and resistance to heat.

• The Journal of the Korean dental association
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• v.11 no.1
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• pp.37-40
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• 1973

The auther measured exothermic tempreature of the 5 kinds of direct resins during polymerization. Direct resins were mixed into the rubber cup(550-600㎣ in volume) with grass rod at room temperature (23.6℃) for 30 seconds and thermometer was placed approximately at the geometric center of the resin mass in the rubber cup. Polymer-monomer ratio was determined by instruction of the packages. The results were as follows. 1) The heat generated during polymerization was under 47.3℃. 2) The time at which the highest temperature is reached during polymerization was within 20.5 minutes. 3) Slow curing resins produced lower heat than quick curing resins and quick curing resins presented higher temperature than slow curing resins. 4) The highest temperature was sustained momentarily.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.465-468
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• 2006

This paper investigates the effect of curing conditions on the strength improvement of polymer-modified mortars using epoxy resin with various curing methods. The polymer-modified mortars using epoxy resin are prepared with various polymer-cement ratios, and subjected to standard, hot water, heat cure and autoclave cures. The epoxy-modified mortars are tested for flexural and compressive strengths at desired curing methods. From the test results, the flexural and compressive strengths of the epoxy-modified mortars are hardly improved by the autoclave and hot water cures compared to the ideal cure of $20^{\circ}C$. Among the four types of curing methods, the strengths of the heat cured epoxy-modified mortars is largely improved. Especially, it is obtained in the mortars sealed with PVDC film.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.39-40
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• 2022

This study is intended to examine the curing effect of the combination of the bubble sheet on the concrete by analyzing the temperature profile and core strength of the simulated concrete structure. The test results relvealed that the average temperature of the concrete applying photothermal sheet overlapped with the double bubble sheet at the bottom was 23.5℃, which had the highest insulation and insulation effect compared to other types of surface insulation curing sheets, and the core strength increased by up to 56%.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.181-186
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• 1999

When the expansive additives are used in concrete to reduce the shrinkage cracking, it shows variable properties with the curing method and curing temperature. Therefore, in this study, the experiments are perfomed to present the expansion of cement mortar by varying the unit additions of expansive additives and the curing method. According to the test results, the order of expansion by curing method, which is caused by hydration heat of cement, is follows ; curing at water > curing at air after curing at water for 7 days > curing at air. Cement mortar using expansive additives shows that high expansion is place with rise of temperature.

• Journal of the Korea Institute of Building Construction
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• v.21 no.2
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• pp.97-104
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• 2021

This study aims to develop non-sintered cement that can replace the Portland cement by utilizing industrial by-products. As a suggestion, the physical properties of non-sintered cement mortar depending on the curing method were investigated with ground granulated blast furnace slag, class C fly ash, and class F fly ash. As a result of the study, it was found that the strength performance and absorption rate were improved through the heat treatment process after steam curing. It was confirmed through crystal phase analysis that the hydration was accelerated after heat treatment, and the bonding material formed a dense internal structure.

• Journal of Technologic Dentistry
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• v.33 no.1
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• pp.25-35
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• 2011

Purpose: There are some advantages of the acrylic resin denture base ; appropriate strength, volume safety, simple processing apparatus, and low cost. But, it have a weakness for fracture by intense pressure or shock. However, the repairs for resin denture base are possible using various materials and techniques. There is a few studies in repairs for resin denture base, but not clinical researches. And there is no studies in absorbed saliva into the region of fracture and bond strength. This study is to observe re-bond strength of resin denture base after repairing under saliva absorption. Methods: The samples were made of heat curing resin and the rectangular parallelepiped specimens which were 50mm long, 10mm wide and 3mm high. The four different groups immersed in the artificial saliva for 2 weeks were prepared, 1) no repaired control samples, 2) immediately repaired samples, 3) repaired samples after 1 day dry, and 4) repaired samples after 3 days dry. The prepared samples were repaired by two different curing materials, self curing resin and heat curing resin method. Each groups composed of 10 specimens were experimented with the three point bending tests for bonding strength measuring Results: There were under condition absorbed in the artificial saliva and repaired by self curing resin method, repaired specimens after 1 day and 3 days dry groups had higher values of bonding strengths than control group, and bonding strengths of immediately repaired samples were similar to those of control samples (p<0.05). There were under condition immersed in the artificial saliva and repaired by heat curing resin method, immediately repaired samples showed similar values to bonding strengths of control groups, and repaired samples after 1 day and 3 days dry groups were lower than those of control group (p>0.05). Conclusion: In this study, the repairs for resin denture base were remarkably high values of bonding strengths than those of the past, and showed that have stable bonding strengths independent of saliva absorption of denture base, so present repairs for resin denture base can be performed, regardless of saliva conditions.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2005.05a
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• pp.45-48
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• 2005

This study is basic experiment for estimating influence of strength by curing temperature of concrete's heat of hydration and estimate relationship of compressive strength development by initial curing temperature factor, and then asume temperature factor which influence compressive strength development and for showing basic document of qualify control. According to the result of cement mortar by the curing temperature factor high-curing temperature shows high strength on 3 day compare with low curing-temperature, shows higher strength than the piece of high curing temperature.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.6
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• pp.976-981
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• 2012

In this study, hardness, microstructure and temperature of glass transition are measured respectively by using SEM (Scanning electron microscope) and DSC (Differential scanning calorimeter) to analyze the effects on material properties by after-curing in the epoxy resin. As the result of hardness test according to the after-curing conditions, the higher the temperature of after-curing, hardness and heat resistance are, the higher hardness is. As a result of microstructure for each specimen by SEM, it could be confirmed that the specimen with after-curing has more dense fracture surface. It is also found that temperatures of glass transitions by DSC are comparatively higher in the specimens with after-curing, and the differences between after-curing conditions are negligible.