These household applications for engineering plastics, which turned up at the recent K Fair in Düsseldorf, Germany, have implications beyond the purely domestic. They show how plastics can address essential engineering problems like the balance between mechanical properties and cosmetics, sound energy management, and thermal insulation.
PurSonic. You have to bust open some drywall to find these new home theater speakers from Puren GmbH. The company's new PurSonic audio systems turn portions of a wall or ceiling into active speaker surfaces, thanks to a combination of proprietary amplifiers and thin rigid urethane panels that integrate into existing wall structures. The system owes some of its dazzling sound quality to a custom urethane formulation from Bayer MaterialScience. Chemistry and processing tweaks let Bayer's engineers vary properties that influence sound quality. These included not only the overall density and stiffness of the rigid urethane but also the cell size, shape, and ratio of open to closed cells. PURSONIC tested hundreds of these formulations before settling on material that both sounded great and would do so in a panel less than 8 mm thick. For more information, visithttp://rbi.ims.ca/4385-541.
Not so drafty
Neopor. Passive houses, environmentally friendly dwellings that maintain comfortable interior temperatures without active heating and cooling systems, work largely because they minimize heat loss through the use of efficient thermal insulation systems. For a new passive dwelling project in Switzerland, Anliker AG turned to a new high-tech version of a familiar wall insulation material, or expanded polystyrene (EPS) board. Unlike traditional EPS, BASF's Neopor contains infrared absorbers and reflectors that just about eliminate thermal radiation effects for a dramatic drop in thermal conductivity—and a reduction in the amount of polystyrene needed to reach a given insulation level. For example, a Neopor board with a bulk density of 15 kg/m3 offers a thermal conductivity of 0.032 W/mK. Conventional EPS, by contrast, needs about twice as much raw material, or a density of 32 kg/m3, to achieve the same thermal conductivity levels. For more information on Neopor, visit http://rbi.ims.ca/4385-542.
Delrin. Slick touchscreen controls may be the most noticeable feature on the "Premium Touch," an intelligent washing machine from Slovenian appliance maker Gorenje. But the machine also sports the first commercial use of DuPont's paintable acetal, a high-performance plastic that did not previously lend itself to easy decoration. The machine's integrated door handle and latch system are injection-molded from Delrin DS500 acetal and then painted with DuPont's Cromax water-borne, chromium-free paint. In other applications, parts can also be plated with metals. A proprietary etching process prepares the acetal parts for decoration—and does so without degrading mechanical properties. And that balance of cosmetics and property retention is the key to the new material's success in this application. With its prominent placement on a consumer product, the handle has to look good. But its latching role demanded robust fatigue performance and dimensional stability, even in wet environments. In past machines, these functional and cosmetic requirements forced Gorenje to make the handle and latch as an assembly of ABS and metal. For more information on paintable Delrin, visithttp://rbi.ims.ca/4385-543.