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Monthly Archive - July 2016 (page 17)brain teasers, puzzles, riddles, mathematical problems, mastermind, cinemania... These are the tasks listed 161 to 170. |
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Waldo SemonDied 26 May 1999 at age 100 (born 10 Sep 1898).American chemical engineer who invented plasticized PVC (vinyl). In 1926's, he discovered how to convert polyvinyl chloride from a hard, unworkable substance to a pliable one. It is now used in hundreds of products such as floor tile, garden hose, imitation leather, shower curtains, and coatings. It is produced in larger quantities than any other plastic except polyethylene. Semon also made pioneering contributions in polymer science, including new rubber antioxidants. His technical leadership led to discovery of three major new polymer families: thermoplastic polyurethane, synthetic "natural" rubber, and oil-resistant synthetic rubbers. Semon held 116 U.S. patents. |
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