Semon, Waldo

Semisynthetic metalworking fluids, 1 22, 15 240-241 Semolina, 26 284 Semon, Waldo, 25 628 Senarmontite, 3 41, 58 Sensible heat transfer, 13 196 Sensing, inclusion compounds in, 14 185 Sensit... 

E. M. Smith, ed., Waldo Eonsbury Semon, A Man of Ideas The Inventor of Plasticic d Polyvinyl Chloride, The Geon Co., Cleveland, Ohio, 1993. 

One was when he addressed a diverse assembly of students, faculty, industrial scientists, and businessmen at Kent State University in the honor of the inventor and educator Waldo L. Semon (1). Speaking slowly, gesticulating, and smiling he... 

Mark, H. F. "Waldo Semon Lectureship Series" Kent State University Kent, Ohio, November 3, 1978. 

Waldo Semon was responsible for bringing many of the PVC products to market. As a young scientist at BF Goodrich, he worked on ways to synthesize rubber and to bind the rubber to metal. In his spare time, he discovered that PVC, when mixed with certain liquids, gave an elastic-like, pliable material that was rainproof, fire resistant, and did not conduct electricity. Under the trade name Koroseal, the rubbery material came into the marketplace, beginning around 1926, as shower curtains, raincoats, and umbrellas. During World War II, PVC became the material of choice to protest electrical wires for the Air Force and Navy. Another of his inventions was the SR patented under the name Ameripol that was dubbed liberty rubber since it replaced NR in the production of tires, gas masks, and other military equipment. Ameripol was a butadiene-type material. 

Waldo Semon patented the use of tricresyl phosphate as a plasticizer for PVC in 1933. This was later replaced by the less toxic di-2-ethylhexyl phthalate (DOP), which is now the most widely used plasticizer. The worldwide production of plasticizer is on the order of 3.2 million tons annually. Volume-wise, about 90% of the plasticizers are used with PVC and PVC-containing systems. 

W. W. Hartman J. Ross Robertson I. M. Heilbron Waldo L. Semon E. C. Kendall F. C. Whitmore E. P. Kohler... 

Since cellulose nitrate is intractable, in 1870 John W. Hyatt added camphor as a plasticizer to flexibilize this plastic. Some 60 years later, Waldo Semon used tricresyl phosphate as a plasticizer for PVC. Dialkyl phthalates, such as dioctyl phthalate (DOP) and other alkyl phthalates which replaced the more toxic tricresyl phosphate, are now used as plasticizers primarily for PVC at an annual rate of 1 million tons. 

Polymerized vinyl chloride as a homopolymer is hard and brittle, making it difficult to work and impractical as a commercial material. In 1926, Waldo Lonsbury Semon (1898—1999) was working for B. F. Goodrich searching for a synthetic rubber that could adhere to metal objects. Semon examined vinyl chloride and found that when polyvinyl chloride powder was mixed in certain solvents, he obtained a stiff gel that could be molded into a plastic material. The material s hardness and pliability depended on the mix of solvent and polyvinyl chloride. Semon... 

Polyvinyl chloride (PVC) had been developed by a number of chemical companies in the 1920s. The problem with this material, however, was that it lost resiliency when heated. In 1929, Waldo Semon, a chemist at BFGoodrich, found that PVC could be made into a workable material by the addition of a plasticizer. Semon got the idea of using plasticized PVC as a shower curtain when he observed his wife sewing together a shower curtain made of rubberized cotton. 

It was discovered in the twenties by Dr Waldo Semon when attempts were being made to dissolve PVC that it could be plasticized to give elastomer-like compounds, and since then an extensive variety of plasticizers has been suggested and many introduced commercially. The addition of plasticizers provides materials with a considerable range of flexibility and softness those used most commonly today are esters of C8 to C10 alcohols, such as phthalates, phosphates, and sebacates—particularly dioctyl phtha-late (known also as 2-ethylhexyl phthalate), di-iso-octyl phthalate, and dial-phanyl phthalate. 

Celanese Corporation commercially produces acetate fibers The first mobile, two-way voice-based telephone is invented at Bell Labs Waldo Semon at B.F. Goodrich invents plasticized PVC known as vinyl Polysulfide (Thiokol) rubber is synthesized... 

Industrial development of PVC resins began about 50 years ago. Full commercial scale production started in Germany in 1931 and in the United States in the late 1930s. U.S. production was sparked by the observation by Waldo L. Semon at B. F. Goodrich in 1933 that PVC, when heated in the presence of a high boiling liquid (a plasticizer), became a flexible material that resembled rubber or... 

---