• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 가을 학술논문 발표대회
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• pp.252-253
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• 2021

In this study, butyl rubber, which is the main material constituting the self-adhesive butyl rubber waterproofing sheet, was mixed with reclaimed rubber, and tensile strength, tear strength, peeling resistance strength, and adhesion strength were measured for sample prepared by mixing ratio. As a result, it was confirmed that peeling resistance strength and adhesion strength decreased as the reclaimed rubber content increased, and tensile strength and tear strength did not change significantly.

• 한국의류학회지
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• 제27권9_10호
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• pp.1093-1100
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• 2003

Following a treatment with edible oils and/or washing, the tensile properties of vulcanized rubber were measured to assess the effect of the sorbed edible oil. Rubber soiled with soybean oil, after 8 weeks storage in a 30$^{\circ}C$ incubator, retained 61% of its original strength, and rubber soiled and washed retained the 73%. The strength of the rubber soiled with oil decreased remarkably during the first 2 weeks. After repeating this soiling and/or washing 7 times, the soiled rubber had only 16％ of its original strength, the rubber soiled and washed had 45%. In all cases, breaking elongations were not decreased as much as tensile strengths; therefore , more of the elasticity of the rubber remained than did the strength. From these results it is concluded that washing after soiling with oils is very helpful in maintaining the strength of rubber. In this study, three different surfactant solutions, AS, AE and AS/AE, were used. In the AS solution, the contact angle of the soybean oil was greater and the work of the detergency was the smaller than in either the AE or the AS/AE solution, the loss of the strength of the rubber washed in AS solution did not decrease significantly. These results suggest that rolling-up, emulsification and solubilization also participate in the removal of oil from rubber.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제54권12호
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• pp.561-566
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• 2005

This paper describes electrical resistivity, dielectric strength, thermal conductivity, thermal stability and tensile strength of mica sheet impregnated with silicone rubber resin or silicone rubber resin containing alumina powder. The mica sheet impregnated with silicone rubber resin had higher electrical resistivity, dielectric strength and tensile strength than those of virgin mica sheet. Electrical resistivity of mica sheet impregnated with silicone rubber resin containing alumina increased with increasing the amount of alumina. However, dielectric strength and tensile strength of mica sheet impregnated with silicone rubber resin containing alumina decreased with increasing the amount of alumina. The mica sheet impregnated with silicone rubber resin had lower thermal conductivity than that of virgin mica sheet. However, thermal conductivity of mica sheet impregnated with silicone rubber resin conatining alumina increased with increasing the amount of alumina. In the case of thermal stability, thermal degradation of virgin mica sheet and impregnated mica sheet with silicone rubber resin did not occur up to $1100^{\circ}C$ and $400^{\circ}C$, respectively.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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• pp.553-556
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• 2003

This study is analyzed about the factor of adhesive strength characteristics, curing time, asphalt application, test temperature which are liquid waterproofing membrane of rubber-asphalt and chloroprene-rubber type for concrete bridge deck. According to the results, curing time is shorter, adhesive strength is less in chloroprene-rubber type. And also chloroprene-rubber and rubber-asphalt type are showed high adhesive strength in low temperature.

• Elastomers and Composites
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• 제1권1호
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• pp.41-48
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• 1966

The physical properties of rubber coated fabrics, treated by means of spreading and topping process were studied. 1. The tearing strength of the rubber coated fabrics has shown decreasing tendency in comparison with fabric itself 2. Generally, the tearing strength is inversely proportional to the adhesion. 3. The value of hydrostatic pressure is in proportion to the density and tensile strength of the fabrics. 4. The topping process shows greater difference in adhesion initial and after water immersion than spreading process.

• Computers and Concrete
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• 제20권3호
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• pp.311-318
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• 2017

This paper investigates the utilization of waste tyre crumb rubber as the fine aggregate in precast concrete Paving block (PCPB). PCPB's are generally preferred for city roads, pedestrian crosswalk, parking lots and bus terminals. The main aim of this paper is to evaluate the mechanical properties of wet cast PCPB containing waste tyre crumb rubber. The mechanical properties were investigated using a density, compressive strength, split tensile strength and flexural strength tests at 7, 28 56 days according to the IS 15688:2006 and EN1338. The wet cast method was followed for producing PCPB samples. The fine aggregate (river sand) was replaced with waste tyre crumb in percentage of 5%, 10%, 15%, 20% and 25% by volume. All the test results were compared with the conventional PCPB (Without rubber). The test results indicate its feasibility for incorporating waste tyre crumb rubber in the production of PCPB by the wet cast method.

• Elastomers and Composites
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• 제34권1호
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• pp.31-44
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• 1999

4종류의 고무(NR, SBR, EPDM, BIMS)에 대해 완전가교 고무층과 부분가교 고무층간 계면 결합의 변화에 따른 계면 접착강도를 $30{\sim}120^{\circ}C$ 조건에서 조사하였고, 전자현미경을 이용하여 접착파단면을 조사하였다. 두 개의 완전가교 고무층간 계면에서는 물리적 결합이 계면 접착강도에 주도적인 역할을 하였고, 완전가교 고무층과 부분가교 고무층간 계면에는 물리적 결합과 화학적 결합이 공존하여 계면 접착강도에 영향을 미쳤다. 접착강도가 응집 인열강도와 유사한 수준으로 높을 때 NR은 "계면 노티인열" 형태를, EPDM은 "cross-hatched" 형태를 보였다.

• Elastomers and Composites
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• 제19권3호
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• pp.163-177
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• 1984

The effect of curing temperature increase and sulfur amount added were studied with natural and synthetic rubbers. Also, the effects of TMTD, MBTS and mixture of zinc soaps of high molecular fatty acids added to natural rubber were investigated respectively. The experimental results showed that, in the case of the conventional curing ($145^{\circ}C$), natural rubber, compared with synthetic rubber, gave higher values in elongation, tensile strength, cure rate, and lower values in modulus change. But, at high temperature curing ($180^{\circ}C$), natural rubber showed faster reversion rate, and higher heat build-up compared to synthetic rubber, than in the conventional curing. Also, natural rubber produced at high temperature showed severe degradation in hardness and tensile strength before heat-aging as well as in hardness, modulus and tensile strength after heat-aging. Improved reversion effect was obtained with natural rubber either by blending mixture of zinc soaps of high molecular acids or by applying semi-efficient vulcanization system.

• Steel and Composite Structures
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• 제19권4호
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• pp.843-860
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• 2015

Recycled tire rubber-filled concrete (RRFC) is employed into the steel-concrete composite structures due to its good ductility and crack resistance. Push-out tests were conducted to investigate the static behavior of steel and rubber-filled concrete composite beam with different rubber mixed concrete and studs. The results of the experimental investigations show that large studs lead a higher ultimate strength but worse ductility in normal concrete. Rubber particles in RRFC were shown to have little effect on shear strength when the compressive strength was equal to that of normal concrete, but can have a better ductility for studs in rubber-filled concrete. This improvement is more obvious for the composite beam with large stud to make good use of the high strength. Besides that the uplift of concrete slabs can be increased and the quantity and width of cracks can be reduced by RRFC efficiently. Based on the test result, a modified empirical equation of ultimate slip was proposed to take not only the compressive strength, but also the ductility of the concrete into consideration.

• Elastomers and Composites
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• 제58권3호
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• pp.128-135
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• 2023

To improve the adhesive strength of natural rubber (NR) for a seismic isolation damper, citraconic acid-g-NR (CCA-g-NR) was synthesized via the melt grafting of citraconic acid (CCA) onto NR using an azobisisnomerobutyronitrile (AIBN) initiator. Subsequently, the influence of CCA and AIBN concentrations on the graft ratio G/R (%) and graft efficiency G/E (%) of the CCA-g-NR was investigated. The optimum CCA and AIBN concentrations required to achieve the desired G/R (3.49%) and G/E (49.8%) were found to be 7 phr and 0.13 phr, respectively. Additionally, we studied the influence of CCA-g-NR concentration on the mechanical properties (tensile strength, elongation at break, and modulus at 300%), adhesive strength, and cure characteristics of the rubber compound in the seismic isolation damper. As the concentration of CCA-g-NR increased, the elongation at break and adhesive strength of the compound increased, whereas its tensile strength and modulus at 300% decreased. Moreover, as the concentration increased, the maximum torque decreased and the scorch time was delayed to obtain an optimal vulcanization time.