Optimization of Si‐69 Content in Green Rubber Composites: Establishment and Verification of a Constitutive Model Based on Finite Element Analysis

ABSTRACT Since the introduction of green tires for Michelin in 1992, the dispersion of silica has remained a hot topic in both academic and engineering research. Si‐69 is a silane coupling agent used in rubber materials to improve the dispersion of silica. When the Si‐69 content is too low, dispersion improvement is limited; when the content is too high, it can have a negative impact on the material. In this paper, experiments were designed to verify the properties of the materials by varying the amount of Si‐69. The experimental results show that the dispersion of filler is significantly improved and the heat build‐up is significantly reduced with the increase of Si‐69 at 0–4 phr. At 6–8 phr, the mechanical properties decreased significantly due to the high cross‐linking density. This paper investigates the heat build‐up of composites with varying Si‐69 content through finite element simulation, with the simulated results consistent with experimental findings. Unlike the previous ones, the simulation in this paper does not involve the development of complicated subroutines, and it can better reflect heat build‐up trend of different Si‐69 dosage, which is a simple, convenient and cost‐effective method. This study started from simulation, established a functional relationship between E ″/ E * 2 and the dosage of Si‐69, and performed an extremum analysis on the function to determine the optimal dosage, thereby achieving forward development of composite materials. This integrated approach coupling simulation calculations with functional processing algorithms has established a rigorous quantitative calculation framework for the design of low heat‐generating rubber products. Beyond the dosage optimization of silane coupling agent Si‐69, this method is also applicable to the quantitative optimization of a broad spectrum of other reinforcing fillers (e.g., carbon black, silica) and processing additives.