PREPARATION AND CHARACTERIZATION OF EPDM RUBBER MIXTURE FOR A HEAT RESISTANT CONVEYOR BELT COVER

Abstract

In this paper, the EPDM rubber-based dough recipe for a conveyor belt used in high temperature conditions was developed. As a first step, the silica loading effect on the mechanical and rheological properties was determined.  After selecting the proper coating dough recipe, dough properties were investigated for filler mica, instead of silica, and the influence of paraffinic oil was tested for both silica and mica fillers. The properties of the EPDM rubber blend were investigated with rheometer tests on the semi-finished materials and with mechanical and physical tests (tensile strength, elongation at break, density, hardness, abrasion, heat ageing tests) on the finished coating materials after a vulcanization process. Thermal degradation behaviors of materials were analyzed by the thermal gravimetric analysis (TGA) system, and determination of chemical structure was analyzed by Fourier transform infrared spectroscopy (FTIR). The physico-mechanical characteristics of EPDM rubber blends were increased with silica loadings. EPDM rubber demonstrates thermal resistance in the temperature range of 150^oC – 160^oC under normal conditions. As a result of the studies conducted, the heat resistance of the coating rubber material was raised to 200^oC by adding silica and paraffinic oil with a higher flash point into the EPDM dough mixture formulae.

Keywords

• EPDM,Filler,Rheometer test,Mechanical properties,Heat-resistance

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