【正文】 ABS blend (PC/ABS). The pact and lightweight phones of today have wall thicknesses in the range of 1 mm. Telephones are a good example of how plastic products evolve over time. Creative product designers make use of new plastic materials and new plastic processing technologies as they bee available in order to improve product performance. Nypro The NYPRO Corporation, with headquarters in Clinton, MA, is a leading global supplier of precision injection molded assemblies and tools. The pany was founded in 1955 as the Nylon Products Corporation with annual sales of less than $1 million. Using borrowed funds, the pany was purchased by Gordon Lankton in the 1960’s. Today, the pany has more than 30 manufacturing facilities around the world, including facilities in the UK, Germany, Russia, India, Mexico, Hungary, and China. NYPRO, sponsor of UML’s ―Precision Injection Molding Laboratory‖, has annual sales that now top $800 million. This year, NYPRO will mold and assemble more than 6 billion plastic parts. That is one part for every man, woman, and child in the world. Mico Kaufman, a Tewksbury sculptor, is most famous for his traditional metal artwork. As a sculptor, his bronze artworks include the ―Homage to Women‖ and ―Indian Maiden‖ which are both located in Lowell. He is also well known for his Presidential Inaugural Metals, including those of Presidents Ford, Regan and Bush. Always on the lookout for new ideas, Mico found his next artistic medium — molten plastic. I finally felt that I had a medium, had the material, where only the imagination was the limit, he says. I was letting my hair down and doing something that I always wanted. Each type of plastic has a temper and personality of its own, so everything you do inspires you to do something more.― Over the past ten years, Mico has been creating plastic artwork in the laboratories of the Plastics Engineering Department at UML. The artwork is created by forming strips of molten plastic as it exits an ―extruder‖. Mico has produced more than 30 plastic sculptures including the one to the right. Mico Kaufman “Very Large” Part Injection Molding This HUSKY 8800 ton clamp injection molding machine is being used to mold ―thermoplastic‖ Jeep Wrangler174。F for an extended period of time. It is also inherently flame retardant and very lightweight. The bination of these properties make Ultem174。. This rapid prototyping equipment, produced by 3D Systems in Valencia, CA, is a fully automated system for the production of prototype plastic parts. The process begins by slicing a ―solid puter model‖ of the proposed part in thin (virtual) layers. A focused ultraviolet laser beam then shines onto a photosensitive liquid epoxy plastic resin bath at selected locations causing the epoxy to polymerize and solidify. The part is built or ―grown‖ one layer at a time. Using this process, prototype parts can be built in a matter of hours, rather than days or weeks as with traditional machining. This has revolutionized the product development process and reduced time to market for new products. In search of a high temperature thermoplastic, scientists at the General Electric Company discovered polyetherimide (PEI) in the early 1980’s. The material was introduced mercially in 1982 with the tradename Ultem174。 and in this use alone has saved thousands of lives. In fact, Kevlar174。, was first marketed in 1971. The fiber was five times stronger than steel (on a strength per weight basis) but about half the density of glass fiber. Kevlar174。s most readily recognized and widely used materials: Kevlar174。 (PI) film, and Teflon174。 (PET) fabric, aluminized Mylar174。 coated woven glass fiber fabric. The tough thermoplastic known as ABS, short for polyacrylonitrile butadiene styrene, was first produced in 1951. At first, ABS was just a “blend” of polystyreneacrylonitrile copolymer (SAN) and butadiene rubber as an impact modifier. However, the properties of the blend were not particularly good. It was then discovered that outstanding impact performance could be obtained if the SAN was chemically grafted onto the butadiene rubber. The grafted version is known as ABS “terpolymer”. The properties of ABS can be fine tuned by controlling the relative ratio of each monomer. ABS is widely used in applications where toughness is required. One of the earliest applications was for football helmets, which are now made from polycarbonate. Today, ABS is most widely used for consumer electronics and business machine housings. General Motors introduced the Chevrolet Corvette in 1953. It was designed by GM’s chief stylist Harley Earl, who was intrigued with the use of glass fiber reinforced plastic as a body material. A total of 300 Corvettes were produced in the first year of production, each containing forty one glass fiber reinforced unsaturated polyester body parts. The 1953 Corvette was available only with a white body and red interior, and sold for $3,. While the Corvette has changed dramatically over its 50 year history, one thing that has not changed is the use of the glass fiber reinforced plastic body. 1953 Corvette 20xx 50th Anniversary Corvette Working independently, Hermann Schnell of Bayer . in Germany and Daniel Fox of the General Electric Company in the US, both discovered polycarbonate in 1953. This optically transparent engineering thermoplastic offers a great balance of stiffness and toughness, heat resistance and electrical insulating properties. It is widely used for durable products such as automotive headlights, tool housings, helmets and puter enclosures. In more recent years, special grades of polycarbonate have been developed for optical recording media. Virtually all CD’s, CDROM’s and DVD’s are manufactured using polyca