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Polypropylene. John Caballero MEEN3344. Polypropylene. Discovery Polypropylene was first polymerized by Dr. Karl Rehn in Germany in 1951 but sadly didn't recognize the importance of his discovery It was then rediscovered on March 11, 1954 by Giulio Natta. Advantages
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Polypropylene John Caballero MEEN3344
Polypropylene Discovery • Polypropylene was first polymerized by Dr. Karl Rehn in Germany in 1951 but sadly didn't recognize the importance of his discovery • It was then rediscovered on March 11, 1954 by Giulio Natta. Advantages • has a high melting temperature 160°C (320°F) which enables it to be exposed to greater temperatures and keep its same shape. Example, dishwasher safe tupperware • Environmentally safe so it can be used in everyday life • is a thermoplastic polymer, can be recycled, number “5” Disadvantages • Polypropylene is liable to chain degradation from exposure to UV radiation • The polymer can also be oxidized at high temperatures, a common problem during molding operations • Quaternary ammonium biocides was found by researchers to be leaking out of polypropylene plastics used in laboratory experiments (A biocide is a chemical substance capable of killing living organisms)
Practical Applications • Biaxially Oriented polypropylene (BOPP) sheets are used to make a wide variety of materials including clear bags like the bags at a department store • highly colorfast, is widely used in manufacturing rugs and mats to be used at home • used in ropes, distinctive because they are light enough to float in water • used to make bottles, Plastic pails, car batteries, wastebaskets, cooler containers, dishes and pitchers, retreading automobile tires
Manufacturing • The largest company to produce Polypropylene is Lyondell-Basell and Dow Chemical Company • Polypropylene is commonly spun into fibers, injection molded, cast into thin films, extruded into sheet and profiles and blow molded • the fiber market accounts for the largest share of polypropylene usage • Polypropylene has a high tensile strength when the molecules are oriented, and a relatively low melt strength; these are the primary requirements for fiber markets.
Sources • Wikipedia, "Polypropylene." 11 Nov 2008 <http://en.wikipedia.org/wiki/Polypropylene>. • BASTIAN, KEVIN. "Polypropylene Offers More for Less ." 11 Nov 2008 <http://www.plasticsmachining.com/magazine/199806/polypro.html>. • recycled items online. 12 Nov 2008 <http://www.recycledproductsonline.co.uk/bullions >. • "safety gear." 12 Nov 2008 <http://www.newrivernets.com/nrn/safety.htm >. • "new and used lab equipment." 12 Nov 2008 <http://www.crscientific.com/plasticbottles.html >. • "recreational dynamics." 12 Nov 2008 <http://www.recreationdynamics.com/shots/UPE-1003.php >. • "Polypropylene Plant." 12 Nov 2008 <http://www.flickr.com/photos/96634714@N00/255431640/>. • "swico." 12 Nov 2008 <http://www.swicofil.com/asotaantifirecrackfiber.html>.