• Elastomers and Composites
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• v.52 no.1
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• pp.35-47
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• 2017

A comprehensive survey of the available literature showed that in the last few decades, there has been a growing interest in the use of thermoplastic vulcanizates (TPVs). TPVs are the second largest group of soft thermoplastic elastomers (TPEs) after styrene-based block copolymers, and offer a wide range of potential and proven applications, including in mechanical rubber goods, under-the-hood applications in the automotive field, industrial hose applications, electrical applications, consumer goods, and soft touch applications. Over the last two decades, TPVs have shown a strong and steady market growth (~12% per year). Commercialized TPVs are commonly based on blends of ethylene propylene diene monomer (EPDM) rubber and polypropylene (PP), and to a lesser extent on combinations of butyl or nitrile rubber with PP. EPDM/PP TPVs are characterized by finely dispersed crosslinked EPDM rubber particles (particles size varying between 0.5 and $2.0{\mu}m$) distributed in a continuous thermoplastic PP matrix. If the rubber particles of such a blend are small enough and if they are vulcanized well enough, then the properties of the blend are generally improved. This review article introduces various topics and aspects relevant to EPDM/PP TPVs. The development of TPVs, the use of various types of crosslinking systems and co-agents as crosslinking agents for PP/EPDM blends, the morphology and rheology of TPVs, and their typical end-use applications are also reviewed.

• Journal of Biosystems Engineering
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• v.18 no.3
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• pp.239-251
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• 1993

Data acquisition system and computer program developed in this study could be well used in engine vibration analysis. The system and program developed were also operated to be able to control measuring interval, number of channels, number of data. The flywheel was specially studied to provide the proper weight with rubber damper for the engine design at low level of vibration. This study was conducted to obtain basic data which affect the engine vibration. The experiment of this study was performed on original weight flywheel, weight-reduced flywheel, weight-reduced and rubber-coated flywheel, weight-reduced and damper-attached flywheel. Avarage of peak value, maximum vibration, power spectrum density based on FFT analysis are major factors of this experiment. Results were obtained as follows : 1. When rubber was inserted in the flywheel rim of which weight was reduced from 32.2kgf to 24.4 kgf, maximum vibration of the engine was decreased 48.3% at X axis, 35.5% at Y axis and 34.6% at Z axis in comparison with the flywheel of original weight. 2. When the flywheel of rubber damper was compared with the original flywheel, the average of absolute vibration for rubber damped flywheel was decreased at X, Y, Z axis and especially its decreasing rate was so high at X-axis comparing with the other flywheel, which implied that rubber damper was very useful to reducing the vibration of the engine at X axis. 3. Hysteresis losses of X, Y, Z axis were greatly decreased in the flywheel with rubber damper on rim. 4. Damped oscillation effect on X and Y axis vibration above average peak vibration by the flywheel of rubber damper on rim was larger than those by the other flywheels. 5. Power spectrums of vibration at real and imaginery part were bi-mode type. The vibration frequency of rubber dampered flywheel which weight is decreased was slightly increased as compared with original flywheel.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.8
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• pp.696-701
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• 2005

This paper was investigated the changes of surface properties of high-temperature-vulcanized (HTV) semiconductive silicone rubber due to oxygen plasma discharge. The modifications produced on the silicone rubber surface by oxygen plasma were accessed using Fourier transform infrared spectroscopy(FTIR), X-ray photoelectron spectroscopy(XPS), contact angle and Surface Roughness Tester. The results of the chemical analysis Showed that C-H bonds were broken due to plasma discharge and Silica-like bonds (SiOx, x=$3\~4$) increased. It is thought that the above changes lead to the increase of surface energy of high-temperature-vulcanized (HTV) semiconductive silicone rubber also, Surface roughness was increased with cleavage of side-chains and oxidation process, it confirmed change as the SEM. The micromorphology of surface and hydrophobicity due to plasma discharge based on our results were discussed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.365-368
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• 2005

The dynamic model was developed to analyze vibration acceleration and ride comfort during the operation of rubber-tired light rail vehicles. The ride comfort for standing passengers was analyzed in accordance with ISO 2631-1, UIC 513R, and CEN Draft prENV 12299 using this model. The result was applied to the detail design of Korean-standard, rubber-tired light rail vehicles, and the detail specifications related to ride comfort was determined based on this result. The ride comfort test was performed along the test track by using 2 car-train, and its result was compared with that of the ride comfort analysis, verifying the validity of the developed dynamic model. It was also verified whether or not the developed Korean-standardized, rubber-tired light rail vehicle met specified target specifications on ride comfort.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1644-1647
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• 2005

This study was aimed at evaluating the structural safety for rubber tired AGT system. Based on these, AGT system which was developed for first time in domestic is need to verify structural safety. So we measured the characteristics of guide-rail, switch rail, side wall in the constructed test track for rubber tired AGT system. Finally, all results of test showed that structural safety of the rubber tired AGT system.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1341-1344
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• 2005

This study was aimed to verify the acceptable contact force between power collector and 3rd rail type conductor rail for the Korean standardized rubber-tired AGT light rail vehicle. The power collector was designed and manufactured to satisfy the Korean standardized Specifications of the rubber-tired AGT light rail vehicle. Based on the dynamic behavior, contact force variation and interruption in the worst installation tolerance of the conductor rail, its initial contact force was set up. At the test track for the Korean standardized rubber-tired AGT light rail vehicle, interruptions, stresses, vibrations, and contact force variations were measured. As the results, initial contact force was verified to ensure power collection stability.

• Korean Journal of Digital Imaging in Medicine
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• v.12 no.1
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• pp.15-18
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• 2010

Main component of radiography barrier aprons is lead. To manufacture a lead-free barrier sheath, barium sulfate and organic iodine-based chemicals should be mixed with rubber. Barrier capacity was tested in the medical field. To improve adaptation of rubber with the mixture, raw materials went through milling, agitation, and extruding processes. Three sheaths were manufactured with 30%, 80%, and 120% sulfate barium, respectively. This study found 10% lower barrier capacity of lead-free barrier than the traditional lead-containing rubber sheath. Problems, however, were confronted during the agitation and extruding processes. Mixing with rubber was a technically demanding job. Inconsistent depth, problems with thermal processing and dissipation were encountered as well.

• Smart Structures and Systems
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• v.6 no.8
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• pp.889-903
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• 2010

Idea of using piezoelectric materials with flexible structures made of rubber-like materials is quite novel. In this study a non-linear finite element model based on updated Lagrangian (UL) approach has been developed for dynamic response and its control of rubber-elastic material with surface-bonded PVDF patches/layers. A compressible stain energy density function has been used for the modeling of the rubber component. The results obtained are compared with available analytical solutions and other published results in some cases. Some results are reported as new results which will be useful for future references since the number of published results is not sufficient.

• Smart Structures and Systems
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• v.8 no.4
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• pp.399-412
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• 2011

This study compares the performance of two smart isolation systems that utilize superelastic shape memory alloys (SMAs) for seismic protection of bridges using energy balance concepts. The first isolation system is a SMA/rubber-based isolation system (SRB-IS) and consists of a laminated rubber bearing that decouples the superstructure from the bridge piers and a SMA device that provides additional energy dissipation and re-centering capacity. The second isolation system, named as superelastic-friction base isolator (S-FBI), combines the superelastic SMAs with a flat steel-Teflon bearing rather than a laminated rubber bearing. Seismic energy equations of a bridge structure with SMA-based isolation systems are established by absolute and relative energy balance formulations. Nonlinear time history analyses are performed in order to assess the effectiveness of the isolation systems and to compare their performance. The program RSPMatch 2005 is employed to generate spectrum compatible ground motions that are used in time history analyses of the isolated bridge. Results indicate that SRB-IS produces higher seismic input energy, recoverable energy and base shears as compared to the S-FBI system. Also, it is shown that combining superelastic SMAs with a sliding bearing rather than rubber bearing significantly reduce the amount of the required SMA material.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1585-1588
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• 2003

Based on the design requirements for the rubber-tired AGT light rail vehicle. the braking system was designed. Its major components are a brake operating unit, a pneumatic-hydraulic transfer, screw compressor, oil separator. air dryer, hydraulic caliper. After the components of braking system were manufactured. some factory tests were executed to evaluate their performances. The Results of these tests can guarantee a performance. safety of the braking system developed.