Lucite Plexiglas polymethyl

Lucite and Plexiglas (polymethyl methacrylate as marketed by du Pont and by Rohm and Haas, respectively) and polystyrene are transparent thermoplastic materials. Their machinability is fairly good but somewhat limited by their thermoplasticity. They are strongly attacked by solvents such as acetone. They can be cemented with solvents alone (trichloroethylene) or with such cements as Duco. Over long periods cracks may develop at points of strain, and discoloration may result from prolonged exposure to strong light. 

A copolymer in region 5 is a typical amorphous, glassy polymer hard, rigid, and usually brittle. Again, if the polymer is pure, it will be perfectly transparent. Polymethyl methacrylate (Lucite , Plexiglas ) and polystyrene are familiar examples of homopolymers with these properties. 

Methyl methacrylate is only one of a family of monomers, including the various esters of acrylic, methacrylic, and ethacrylic acids, which are polymerized to produce the thermoplastic resins known as the acrylates. A wide variety of reactions and starting materials may be utilized for their production however, the principal commercial product is polymethyl methacrylate, sold by Du Pont and Rohm Haas under the trade names of Lucite and Plexiglas, respectively. These materials were introduced to the United States market in 1936 (44) and have received widespread acceptance due principally to their outstanding optical properties. Production in 1949 was reported as about 22,000,000 to 25,000,000 pounds and peak wartime capacity was above30,000,000 pounds. While this can account for only about 2% of the current production of propylene for chemical purposes, the acrylate resins are of considerable commercial importance as they are sold at a relatively high price and are the only materials available that will meet the requirements for certain military and civilian products. 

Methyl methacrylate CH2=C(CH3)—COCH3 Polymethyl methacrylate (Plexiglas, Lucite) Basketball backboards... 

Polymethyl methacrylate (PMMA, Lucite, and Plexiglas) Hard, transparent solid Contact lenses, heart pumps ... 

Polymethyl methacrylate (PMMA), also called Plexiglas, Lucite, or Perspex, is a colorless clear transparent plastic with excellent outdoor stability if UV absorbers are added to the polymer— otherwise, it yellows on exposure to sunlight. Like styrene, it also unzips on heating to reform the monomer. It has poor scratch resistance but was the plastic of choice for early contact lenses. 

Practice Problem B The general stmeture of polymethyl methacrylate, an addition polymer used in Plexiglas and Lucite, is as follows ... 

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