Effect of HNTs and modified HNTs nanotubes on the mechanical properties and swelling resistance of EPDM/SBR rubber blend nanocomposites

Abstract

Abstract The relationship between the structure and mechanical properties of intricate rubber nanocomposites holds the key to enhancing the performance of roofing membranes. This study involves the incorporation of halloysite nanotubes (HNTs) that have been modified with 3-Aminopropyltriethoxysilane (APTES) into blends of ethylene-propylene diene monomer (EPDM) and styrene butadiene rubber (SBR). These blends maintain consistent concentrations, with a composition of 80% EPDM and 20% SBR. This addition aims to assess changes in curing behavior, mechanical characteristics, microstructure, and swelling tendencies. The incorporation of APTES-modified HNTs leads to an increase in minimum torque, maximum torque, and delta torque during the curing process. However, both scorch time and optimal cure time decrease as HNTs content rises. Notably, systems containing 6 parts per hundred rubber (phr) of APTES-modified HNTs exhibit a remarkable 121% enhancement in tensile strength and a 59% increase in stress at 100% elongation. With the escalating concentration of HNTs within the EPDM/SBR nanocomposites, a multitude of alterations come into play. Tear strength, hardness, and resistance to abrasion experience improvements, while elongation at break, rebound resilience, and mole percent uptake undergo reduction. APTES-modified HNTs filler-filled EPDM/SBR nanocomposites exhibited superior performance compared to those filled with unmodified HNTs. The augmented hydrophobic nature of APTES-modified HNTs fosters enhanced particle dispersion, thereby fostering improved mechanical properties, as evidenced in FESEM.