• 한국염색가공학회지
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• 제30권2호
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• pp.77-89
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• 2018

In the case of fiber/rubber composites for tire applications, the interfacial adhesion between fiber and rubber significantly affects the physical properties of the finished products. Generally, organic synthetic fibers used for tire cords are treated with resorcinol formaldehyde latex(RFL) primer on the surface of the fiber to improve the adhesion to rubber. Changes of adhesion between rubber and tire cords might weaken as temperature rises due to overheating of car engine and friction with road. In this study, the effects of temperature on the primer treated polyketone cord/rubber composites and the changes in interfacial adhesion were investigated. Polyketone cord/rubber composites were prepared after RFL solution treatment on the surface of polyketone fibers. After that, composites was thermally aged at different temperature conditions(60, 80, 100, $120^{\circ}C$) and times(1, 5, 10, 15days). The adhesion strength of polyketone cord/rubber composite treated with RFL primer was higher than untreated composite by more than 3 times. After heat aging, the adhesion strength of untreated polyketone cord/rubber composites increased while the RFL treated polyketone cord/rubber composites decreased somewhat.

• Elastomers and Composites
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• 제3권1호
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• pp.32-38
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• 1968

The physical properties of NR-SBR and NR-BR blends were studied. 1. In blending, tensile strength decreased with increase in synthetic rubber contents. It was most effective when the ratio of NR/Syn. R is 75/25. 2. Tensile strength decreased with order of NR, SBR and BR and modulus after aging is proportional of synthetic rubber contents. 3. Elongation is less influenced by synthetic rubber ratio that on the other hand, the decrease of elongation is proportional to synthetic rubber contents after aging. 4. Hardness decreased with increase in the synthetic rubber contents and on the other hand, the hardness increased after aging.

• 자원리싸이클링
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• 제12권2호
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• pp.28-35
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• 2003

폐타이어의 처리방법으로서는 recycling이 가장 최선의 방법 중의 하나이다. 하지만 재활용의 어려움 중에는 경제성의 문제가 있다. 이러한 문제점을 해결하기 위해서는 폐타이어의 입자 크기를 줄이는 방법과 표면처리를 통하여 제품의 물성을 향상시키는 방법이 있다. 본 연구에서는 두 방법을 동시에 응용한 방법으로 폐타이어의 입자크기를 작게 하고 ultrasonic 처리를 하였다. 그 결과로 폐타이어 가황 시스템의 변화를 가져옴으로서 물성의 향상을 알 수 있었다. 이러한 기술은 재활용의 경제성을 높이는 기초기술임을 알 수 있었다.

• 한국정밀공학회지
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• 제30권6호
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• pp.622-628
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• 2013

Due to the development of compounding technology, there is a considerable increase in the number of high performance rubbers in the world. Accordingly, there are rapid growing requests about high performance tires such as UHP tire and Run-flat tire. However, it is extremely difficult to investigate the friction coefficient of tire tread rubbers. An alternative solution must be developed with the reliability of high-speed linear friction test machines. The use of friction test machines can be expected to improve rubber friction researches. In this paper, we propose a new kind of high-speed linear friction test machine. We have designed and manufactured various mechanisms for friction tests. The final goals are to design and manufacture friction test machines that can investigate friction coefficients efficiently and rapidly. The performance of the proposed high-speed linear friction test machine is evaluated experimentally; however additional study should be necessary for safer and more reliable experimentation.

• Smart Structures and Systems
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• 제24권4호
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• pp.553-566
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• 2019

This study aimed to categorize pervious rubberized concrete into fresh and hardened concrete analyzing its durability, permeability and strength. During the globalization of modern life, growing population and industry rate have signified a sustainable approach to all aspects of modern life. In recent years, pervious concrete (porous concrete) has significantly substituted for pavements due to its mechanical and environmental properties. On the other hand, scrap rubber tire has been also contributed with several disposal challenges. Considering the huge amount of annually tire wastes tossing out, the conditions become worse. Pervious concrete (PC) gap has graded surface assisted with storm water management, recharging groundwater sources and alleviate water run-offs. The results have shown that the use of waste tires as aggregate built into pervious concrete has tremendously reduced the scrap tire wastes enhancing environmental compliance.

• Elastomers and Composites
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• 제46권4호
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• pp.318-323
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• 2011

폐타이어고무분말을 재활용하기 위하여 방수시트용 고무분말 복합체를 제조하였으며, 수지 종류와 가교제의 함량이 복합체의 기계적 특성에 미치는 영향을 고찰하였다. EPDM이 부가됨에 따라 고무분말 PE 복합체의 신장율이 3배 이상 증가하는 현상을 나타내었다. 고무분말 충전 복합체에 가교제의 농도가 증가함에 따라 복합체의 강도가 증가하였으며, 특히 재생 폴리프로필렌을 사용한 경우 3배 이상 인장강도가 현저하게 높게 나타났다. 따라서 폴리프로필렌 블렌드물로 고무분말 복합체를 제조하는 경우 신재 폴리프로필렌을 사용하는 것 보다 재생 폴리프로필렌을 사용하는 것이 기계적 특성면에서 효과적인 것으로 나타났다.

• 한국자동차공학회논문집
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• 제22권4호
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• pp.105-110
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• 2014

This paper presents the hysteresis friction of a sliding elastomer on various types of surfaces. The hysteresis friction is calculated by means of an analytical model which considers the energy spent by the local deformation of the rubber due to surface asperities. By establishing the fractal character of the surfaces, the contribution to rubber friction of roughness at different length scales is accounted for. High resolution surface profilometer is used in order to calculate the main three surface descriptors and the minimal length scale that can contribute to hysteresis friction. The results show that this friction prediction can be used in order to characterize in an elegant manner the surface morphology of various surfaces and to quantify the friction coefficient of sliding rubber as a function of surface roughness, load and speed.

• Safety and Health at Work
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• 제3권2호
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• pp.130-139
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• 2012

Objectives: The purpose of this study is to evaluate the tire manufacturing work environments extensively and to identify workers' exposure to hazardous substances in various work processes. Methods: Personal air sampling was conducted to measure polycyclic aromatic hydrocarbons, carbon disulfide, 1,3-butadiene, styrene, methyl isobutyl ketone, methylcyclohexane, formaldehyde, sulfur dioxide, and rubber fume in tire manufacturing plants using the National Institute for Occupational Safety Health Manual of Analytical Methods. Noise, carbon monoxide, and heat stress exposure were evaluated using direct reading instruments. Past concentrations of rubber fume were assessed using regression analysis of total particulate data from 2003 to 2007, after identifying the correlation between the concentration of total particulate and rubber fume. Results: Workers were exposed to rubber fume that exceeded 0.6 mg/$m^3$, the maximum exposure limit of the UK, in curing and production management processes. Forty-seven percent of workers were exposed to noise levels exceeding 85 dBA. Workers in the production management process were exposed to $28.1^{\circ}C$ (wet bulb globe temperature value, WBGT value) even when the outdoor atmosphere was $2.7^{\circ}C$ (WBGT value). Exposures to other substances were below the limit of detection or under a tenth of the threshold limit values given by the American Conference of Governmental Industrial Hygienists. Conclusion: To better classify exposure groups and to improve work environments, examining closely at rubber fume components and temperature as risk indicators in tire manufacturing is recommended.

• Journal of the Korean Wood Science and Technology
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• 제25권4호
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• pp.29-38
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• 1997

The effect and control of wood property of reconstituted composite panels for improved board properties by wood-waste materials and development of combination method for heterogeneous materials have been of interest to the wood science researchers. The purpose of this study is to consider the properties in relation to hot pressing conditions and to develope the optimum hot pressing condition with waste wood and waste tire for the manufacturing of composite boards. The study of composite boards for recycling of wood and waste tire is nothing up to the present. Physical and mechanical properties such as specific gravity, moisture content, swelling coefficient, modulus of rupture and modulus of elasticity in bending test were studied. The condition of 3-stage press time for the lowest moisture content of composite board was $4{\rightarrow}3{\rightarrow}3$ minutes. Specific gravity of composite panels was affected mainly by the amount of rubber chip. Because of the low rigidity and high elasticity in rubber chip, it is considered the composite panel was adequate material in the place of compression load, but not bending load. Therefore, it was concluded that a use of rubber-based wood composite panel is proper to the interior materials such as floor a room than exterior materials. From the test results, the most optimum hot pressing conditions were $4{\rightarrow}3{\rightarrow}3$ minutes for 3-stage press time and $45{\rightarrow}20{\rightarrow}5kg/cm^2$ for 3-stage press pressure. The rubber-based wood composite panel was very excellent in elasticity by combination of rubber chip in comparison with existing other wood-based materials. Therefore, it was considered that rubber-based wood composites can be applicable to every interior materials such as floor a room and will be expected to effective reuse and recycle of waste tires and wood-waste materials, and will be contribute to protection of environment pollution in earth.

• 한국염색가공학회지
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• 제34권2호
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• pp.109-116
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• 2022

Tire codes are made of materials such as hemp, cotton, rayon, nylon, steel, polyester, glass, and aramid are fiber reinforcement materials that go inside rubber to increase durability, driveability, and stability of vehicle tires. The reinforcement of the tire cord may construct a composite material using tires such as automobiles, trucks, aircraft, bicycles, and fibrous materials such as electric belts and hoses as reinforcement materials. Therefore, it is essential to ensure that the adhesive force between the rubber and the reinforced fiber exhibits the desired physical properties in the rubber composite material made of a rubber matrix with reinforced fibers. This study is a study on the heat treatment conditions for improving the adhesion strength of the tire cord and the reinforced fiber for tires. The core technology of the drying process is a uniform drying technology, which has a great influence on the quality of the reinforcement. Therefore, the uniform airflow distribution is determined by the geometry and operating conditions of the dryer. Therefore, this study carried out a numerical analysis of the shape of a drying nozzle for improving the performance of hot air drying in a dryer used for drying the coated reinforced fibers. In addition, the flow characteristics were examined through numerical analysis of the study on the change in the shape of the chamber affecting drying.