EXPERIMENTAL INVESTIGATION OF THE STRESS RELAXATION BEHAVIOURS OF EPDM SYNTHETIC RUBBERS

Year 2015, Volume: 33 Issue: 3, 365 - 375, 01.09.2015

Uğur Mazlum Vahap Vahapoğlu Sami Karadeniz

Abstract

Rubber type materials are preferred because they are suitable for use in many engineering applications besides their elasticity . EPDM rubber show outstanding heat, ozone and weather resistance and has excellent electrical properties. Therefore this rubber as an elastomer is an engineering material that has wide range of applications in industry such as door and window seals, radiator, garden and heating hoses, tubing, washers, belts, electrical insulation, roofing membrane and rubber mechanical goods.
In this works, the stress relaxation behaviour of EPDM rubber at the room temperature were experimentally investigated. Applied to the hardness EPDM samples were subjected to different loading programs. In addition, for the loading programs that were implemented, it is shown that for the EPDM rubbers tested the stress relaxation curves obtained at different stretch ratios may be represented by a single representative curve for the specimens having the same hardnesses.

Keywords

Rubber, EPDM rubber, hardness, elastomers, stress relaxation, stretch ratio

References

• [1] Spetz, G., Stress Relaxation. Test Methods, Instruments and Lifetime Estimation, Technical Report, 2000.
• [2] Tobolsky, A.V., Prettyman, I.B., ve Dillon, J.H., Stress Relaxation of Natural and Synthetic Rubber Stocks, Journal of Applied Physics, 15, 380-395, 1944.
• [3] Armah, J.C., Birley, A.W., Fernando, K.P., Hepburn, C., ve Tahir, M., Stress Relaxation Measurements on Rubbers in Compression. Equipment and Methodology, Rubber Chemistry and Technology, 59, 5, 765-778, 1986.
• [4] Björk, F., ve Stenberg, B., Effects of Air and Oil on Stress Relaxation of Nitrile Rubber, Silicone Rubber and Fluorocarbon Rubber, Kautschuk and Gummi Kunststoffe, 41, 1, 44-47, 1988.
• [5] Davies, C.K.L., De, D.K., ve Thomas, A.G., Characterization of the Behavior of Rubber for Engineering Design Purposes: Stress Relaxation Under Repeated Stressing, Progress in Rubber and Plastics Technology, 12, 3, 208-220, 1996.
• [6] Kostov, G.K., ve Petrov, P.C., Stress-Relaxation Study of Tetrafluoroethylene–Propylene Rubbers, Polymer, 36, 19, 3683-3686, 1995.
• [7] Stenberg, B., Björkman, T., ve Dickman, O., Dynamic Mechanical Relaxation of Compressed Rubber Cylinders, Polymer Testing, 3, 63-68, 1982.
• [8] Mackenzie, C.I., ve Scanlan, J., Stress Relaxation in Carbon-Balck-Filled Rubber Vulcanizates at Moderate Strains, Polymer, 25, 4, 559-568, 1984.
• [9] Oono, R., Stress Relaxation in Carbon-Black-Filled Styrene-Butadiene Rubber, Journal of Polymer Science: Polymer Physics Edition, 12, 1383-1394, 1974.
• [10] Sullivan, J.L., The Relaxation and Deformation Properties of a Carbon-Black Filled Elastomer in Biaxial Tension, Journal of Polymer Science: Polymer Physics Edition, 24, 161-173, 1986.
• [11] S.Ronan, T.Alshuth, S. Jerrams, An Approach to the Estimation of Long-Term Stress Relaxation in Elastomers, Prüfen Und Messen Testing and Measuring, 2007.
• [12] Vahapoğlu, V., Kauçuk Türü Malzemelerin İnelastik Özelliklerinin Deneysel Olarak İncelenmesi, Doktora Tezi, KTÜ Fen Bilimleri Enstitüsü, 2006.
• [13] İ. Yazıcı, V. Vahapoğlu ve A. Özdemir, Bilgisayar Tabanlı Endüstriyel Amaçlı Çekme Deney Cihazı Otomasyonu, III. Otomasyon Sempozyumu ve Sergisi, s111-113, 11-12 Kasım 2005, Denizli.
• [14] V. Vahapoğlu ve S. Karadeniz, Stiren Bütadien Kauçuğunda (SBR) Gerilme Gevşemesinin Deneysel Olarak İncelenmesi, 11th International Materials Symposium, 19-21 Nisan 2006, Denizli.
• [15] Berry, J., Helical Spring Stress Relaxometer, Rubber Chemistry and Technology, 30, 889-894, 1957.