The transition towards sustainable, high-performance tyre technologies has accelerated the adoption of silica as a reinforcing filler, offering significant environmental and functional advantages over carbon black. This transition is of critical importance in light of the fact that tyre production and wear contribute substantially to global CO2 emissions, microplastic pollution, and resource depletion throughout their life cycle. However, the inherent polarity discrepancy between hydrophilic silica and hydrophobic elastomers, such as styrene−butadiene rubber (SBR), persists as a significant impediment to the attainment of uniform dispersion and robust interfacial adhesion. This review critically examines chemical strategies for elastomer functionalization that enable improved silica compatibility, highlighting three major pathways: (i) functionalization during polymerization, particularly via living anionic polymerization, which affords precise control over architecture and chain-end chemistry; (ii) post-polymerization modification, with emphasis on thiol−ene “click” reactions for efficient grafting of polar moieties under mild conditions; and (iii) depolymerization-driven approaches, which valorize waste rubbers into telechelic oligomers, advancing circular economy principles. A mapping of functional groups, silanes, mercaptans, epoxides, and amino derivatives drawn from scientific and patent literature is provided, correlating chemical design with enhanced filler dispersion, reduced rolling resistance, and improved wet grip. Despite notable progress, challenges persist in industrial scalability, cost-effectiveness, and environmental impact. Future directions should prioritize green chemistry paradigms, multifunctional elastomers, and advanced characterization to unlock next-generation tyre materials aligned with sustainability goals and global efforts to mitigate environmental burdens.
Pitari et al. (2026) studied this question.