Waldo Semon

Semon put his name into the history books for inventing vinyl, the world's second most used plastic. Semon also devised the formula for bubble gum, which he patented along with vinyl in 1926. Semon found the formula for vinyl by mixing a few synthetic polymers, and the result was a substance that was elastic, but wasn't adhesive. In all, Semon held 116 patents, and was inducted into the Invention Hall of Fame in 1995 at age 97.