Curing characteristics, tear, fatigue, and aging properties of bentonite‐filled ethylene‐propylene‐diene (EPDM) rubber composites

Abstract

This article investigates how the presence of bentonite clay in ethylene‐propylene‐diene (EPDM) composite affects curing characteristics, tear strength, fatigue, and aging properties. The process of compounding of EPDM/Bt composite was carried out by two‐roll mills and the compound was compressed into sheets at 150°C. Monsanto Disc Rheometer was used to determine the curing characteristics, whereas its tear strength was measured by Instron machine. The aging of EPDM/Bt composite was carried out by putting the samples into a 100°C oven for 48 h. Meanwhile, the fatigue strength of the EPDM/Bt composite was measured through Fatigue To Failure Test machine. Results indicate that the curing time (t90) and minimum torque (ML) of EPDM/Bt composite increases with every increase in Bt loading. The scorch time (ts2) increases only after 30 phr was added in EPDM/Bt composite and it continue to rise until 90 phr Bt. Meanwhile, maximum torque (MH) increases with Bt loading and decreases after 90 phr of Bt was added. Tear properties of EPDM/Bt composite have found to be increased with Bt up to 90 phr. The resistance of EPDM/Bt composite toward aging also increases but up to 70 phr of Bt and this can be seen in the increased percentage of retention in EPDM/Bt composite. Fatigue life, however, decreases with increases in Bt loading. Morphological study carried out through scanning electron microscope suggests that there is a buildup of agglomeration when excessive amount of Bt is added into EPDM/Bt composite. This addition leads to the poor properties of EPDM/Bt composites. J. VINYL ADDIT. TECHNOL., 24:E77–E84, 2018. © 2017 Society of Plastics Engineers

Construction of a percolation zone for electrostatic discharge in EPDM/CB composites: A comprehensive mechanism to attain the optimum physico‐mechanical properties

“…The maximum acceptable changes in hardness should be approximately 8 Shore A and 15 Shore A after heat aging at 125 C for 72 h and heat aging at 125 C for 1000 h, respectively. 15,23 The developed composite should possess a minimum tensile strength of at least 10 MPa, a minimum elongation at break of 350%, and a compression set limited to 35% to endure vibrations and subsequent noise. The changes in tensile strength and percentage elongation during heat aging should remain within a moderate range.…”

“…Additionally the peak at 1450 cm À1 is attributed to the C H bending of the methyl group. [15][16][17]33 FTIR spectrum of sulfur vulcanized EPDM sample E (Figure 5B) displays strong peaks at 2923 cm À1 and 2848 cm À1 which results from the symmetric and asymmetric stretching of the C H bond in CH 2 groups. Moreover a weak band at 1473 cm À1 is due to C H scissoring and that at 1379 cm À1 are due to C H rocking of methyl group.…”

“…Moreover a weak band at 1473 cm À1 is due to C H scissoring and that at 1379 cm À1 are due to C H rocking of methyl group. [15][16][17]33…”

“…Ismail et al delved into the curing characteristics, tear, fatigue, and aging properties of bentonite(Bt)-filled ethylene-propylene-diene (EPDM) rubber composites. 15 The paper thoroughly explains the variations in curing characteristics, such as optimum cure time, scorch time, minimum torque, and maximum torque, with Bt loading. Xiong et al presented exceptional work on silica-reinforced ethylene propylene diene monomer/ polypropylene thermoplastic vulcanizates with interfacial compatibilization by methylacrylate.…”

Fatigue behaviour of an industrial synthetic rubber

“…Moreover, this rubber matrix presents little or no strain-induced crystallization which leads to a lower resistance to fatigue crack growth when compared to natural rubber [3][4][5]. Finally, it has to be underlined that compared to natural rubber, only few scientific papers are dealing with the fatigue behaviour of EPDM [2][3][4][5][6][7][8][9][10].…”