Dispersion state and hyperelastic behavior of tire tread compounds reinforced with nanoclay: Uniaxial tensile and compression studies

Abstract

Tire‐tread compounds based on natural rubber, butadiene rubber, and styrene‐butadiene rubber (65/20/15) were reinforced with Cloisite 15A. Clay state‐of‐dispersion in the ternary matrix (clay aspect ratio and clay/matrix interface yield strength) was estimated using Halpin–Tsai, Guth, and Leidner–Woodhams–Pukanszky micro‐mechanical models. The aspect ratio suggested by Halpin–Tsai (9.7) and Guth (16) models both propounded partially intercalated microstructure. Transmission electron microscopy micrographs indicated higher reliability of Halpin–Tsai theory. Wetting parameter values indicated the affinity of Cloisite 15A to disperse in butadiene rubber. However, it seems that clay particles were not provided with proper compounding conditions to further stabilize their thermodynamic state. The poor matrix/clay adhesion was responsible for the decrease in matrix/clay interface strength and thickness upon increasing clay content according to Leidner–Woodhams–Pukanszky. Hyperelastic modeling was conducted using Abaqus software (five strain energy potential forms) on the basis of large deformation uniaxial tension/compression measurements. Effect of nanoclay on the crosslink‐density of samples was justified by C10 (Mooney–Rivlin) and locking‐stretch (Van der Waals) values. The sample containing 1 phr nanoclay presented the best fit to the hyperelastic models among the rest conforming to its small value of global interaction parameter “a”(Van der Waals model) calculated explaining minimum deviations. Overall, Marlow and Ogden provided the best consistency with the experimental stress–strain results.

Investigation of rubber flow during tire shaping process by experiment and numerical simulations

“…[25][26][27][28] Marlow model characterizes the hyperelastic mechanical behavior of unvulcanized rubber, and the Prony series characterizes the relaxation characteristics of unvulcanized rubber. [29][30][31]…”

“…During the shaping process, unvulcanized rubber shows obvious hyperelastic and viscoelastic mechanical behavior 25–28 . Marlow model characterizes the hyperelastic mechanical behavior of unvulcanized rubber, and the Prony series characterizes the relaxation characteristics of unvulcanized rubber 29–31 …”

Experimental investigation of impact resistance and compression behavior of CF/PEEK laminates after hot‐press fusion repair with different stacking sequences

“…In recent years, carbon fiber-reinforced polymer composites have been widely used in aerospace and vehicle industries. [1][2][3][4][5] With the development of high-performance composites, the application of aircraft structures has been developed from secondary load-bearing structures to primary ones, such as wing fixed leading edges, ribs, clips, and angled profiles in parts of Airbus and Boeing commercial aircraft. 6 Due to the service environment, low-velocity impact (LVI) damage is inevitable for thin composite laminated structures.…”

Improving the mechanical properties and curing characteristics of styrene‐butadiene rubber/butadiene rubber composites by incorporating silicon carbide

“…Compared with conventional ZnO, the modified ZnO led to faster crosslinking and better mechanical properties for the SBR/BR‐based composites. Moreover, to gain a better understanding of filler–polymer interaction, various micromechanical molds were used by Shokoohi 38 to evaluate the impact of nanoclay's characteristics on its dispersion in the ternary blends of SBR/BR/NR. It has been found that the fillers play a crucial role in the improvement of mechanical and thermal properties of rubbery blends because of the nanoclay's specific structure.…”