Researchers at the University of South Florida, led by Professor David Simmons, solved a long-standing puzzle about reinforced rubber. The team published its results in the journal Proceedings of the National Academy of Sciences and included a postdoctoral scholar and a doctoral student.
They ran 1,500 molecular dynamics simulations that totaled about 15 years of computing time on a large campus cluster. Using refined models of carbon black and its dispersion in rubber, the group found that a Poisson’s ratio mismatch explains reinforcement. Carbon black particles act like tiny supports and prevent thinning when the rubber is stretched, which makes the material stiffer and stronger. The discovery could help improve tire design and other rubber parts.
Difficult words
- reinforce — to make something stronger or more firmreinforced
- simulation — a computer model of how something behavessimulations
- dispersion — the spreading or mixing of small particles
- mismatch — a difference when two things do not match
- stiff — not easy to bend; firm or rigidstiffer
- carbon black — a fine black material used in rubber
Tip: hover, focus or tap highlighted words in the article to see quick definitions while you read or listen.
Discussion questions
- Do you think better tire design is important? Why or why not?
- Have you seen rubber parts that look strong or reinforced? Where?
- Do you think scientists need many computer hours to solve material problems? Why?
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