Scientists finally explain what makes reinforced tires tough for 100 years

Carbon black flips how rubber responds to stretching

A decades-old mystery about how reinforced rubber stays extraordinarily strong may be solved. Researchers at the University of South Florida used about 1,500 molecular simulations to show that carbon black particles stop rubber from thinning as it stretches, forcing the material to resist volume changes. That shift in behavior helps explain the toughness behind tires and other reinforced elastomers.