Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE Surface-modified calcium sulfate whiskers from industrial gypsum waste are combined with silica in styrene-butadiene rubber to form a synergistic filler system. This system establishes robust covalent interfacial bonding, simultaneously enhancing mechanical and dynamic properties. The approach valorizes solid waste while offering a sustainable pathway to high-performance rubber materials for advanced tire applications.

ABSTRACT
To achieve value-added utilization of industrial solid waste and develop sustainable rubber reinforcing materials, this paper employed silane coupling agent Si-69 for surface modification of calcium sulfate whiskers (CSW). The modified whiskers (M-CSW) were blended with silica to establish a synergistic filler system based on solution-polymerized styrene-butadiene rubber (SSBR). Following successful modification, the hydrophobicity of CSW significantly increased, with the contact angle rising from 17° to 126°. Experimental results indicate that at the optimal filler content of 5 phr, compared to composites containing only silica, the modified composite exhibits a 14.3% increase in tensile strength, a 12.2% improvement in elongation at break, and an 8.7% enhancement in tear strength. tanδ at 0°C increased by 2.9% (improved wet traction performance), while tanδ at 60°C decreased by 20.8% (reduced rolling resistance). This approach not only enables effective utilization of industrial solid waste but also enhances the physical and mechanical properties of composites. This study represents a meaningful exploration into the rational application of industrial solid waste (CSW) and holds significant engineering implications.