Sustainable use of fly ash waste in tire tread rubber: Characterization of physical properties and environmental impact assessment.

This study explores the use of fly ash (FA), a waste material, to partially replace zinc oxide (ZnO) as an activator in tire tread processing. Reducing ZnO addresses its environmental risks, particularly the impact of ZnO leakage into aquatic ecosystems throughout the tire's life cycle. The FA was altered by including rubber compound with and without ZnO, using ZnO-to-FA ratios of 3:0 (control), 2:1, 1:2, 0:3, or 0:5 parts per hundred of rubber (phr).