Title: Scientists Discover New, Self-Repairing Plastic Date: March 4, 2002 For more information on these science news and feature story tips, please contact the public information officer at the end of each item at (703) 292-8070. Editor: Josh Chamot SCIENTISTS DISCOVER NEW, SELF-REPAIRING PLASTIC A team of chemists and engineers has developed a strong, transparent plastic that can mend itself if fractured. The discovery is expected to lead to the creation of self-repairing products for industrial, military and scientific applications. Fractures in the new polymer, called Automend, can be healed without adding catalysts or other chemicals by heating the material to 240-250 degrees Fahrenheit (about 120 degrees Celsius). The National Science Foundation (NSF)-funded scientific team was led by Fred Wudl, director of the Exotic Materials Institute at the University of California, Los Angeles (UCLA), and reported its findings in the Mar. 1 issue of Science. The material was created while Wudl's team was attempting to produce a material as hard as diamond. The scientists obtained additional funds to branch off into this separate but related area of research. The special provision is reserved for rare occasions when an accomplished scientist is given the opportunity to extend his or her primary research goals to pursue an equally promising objective. According to Wudl, the self-healing plastic is potentially useful for products such as electronic devices that heat and cool frequently and large lenses that would retain their shape if cracked and repaired. Because the material is transparent to electromagnetic waves, it could be used to house radar or communications equipment. [Amber Jones] NEW MATERIALS KEY TO SHRINKING MEMORY DEVICES Scientists at the University of Minnesota recently announced a new milestone in the miniaturization of logic and memory components for computers and other electronic devices. As devices shrink, so too must the thin films of silicon oxide at the heart of the machines. However, at some point the insulating properties of silicon oxide films diminish. Chemist Wayne L. Gladfelter and his colleagues, with support from NSF, have perfected a method to optimize the physical properties of high-dielectric materials. These electrically insulating materials are being considered as replacements for silicon oxide. Gladfelter s team has developed a chemical vapor method of depositing three metal oxides on a single wafer in various combinations to achieve size and performance objectives. The researchers reported their results in the February 2002 issue of Chemistry of Materials. [Amber Jones] RESEARCHER CATALOGS VAST DATABASE OF TRADITIONAL PLANTS USED BY NATIVE AMERICANS A scholar at the University of Michigan-Dearborn has compiled information on plants used by Native Americans for foods, drugs, dyes and fibers -- more than 47,000 uses for nearly 4,000 species of plants. Through an NSF grant of $256,000, anthropology professor Daniel E. Moerman analyzed the relationship of the 4,000 species with the entire collection of plant species in North America (about 28,000) and also their relationship to plant species with medicinal value (about 2,800). Pharmacologists are uncovering medical applications, such as the uses of cattail for treating burns, while native groups are using the data to reconstruct habitats and build native medicinal herb gardens. A school district in the Four Corners region of the U.S. is also using the database to put together a bilingual (English and Navajo) website that shows how local native people used plants. [Bill Harms] For more information, see: http://www.umd.umichgian.edu/cgi-bin/herb ALGORITHMS FOR AIRLINES: NEW MATH MODEL SAVES TIME, MONEY To plan flight schedules, airlines must match capacities with demands, and weigh the costs of non-stops flights and through connections against the prices passengers are willing to pay. In research partially funded by NSF, a team of operations researchers and industrial engineers developed a mathematical model that efficiently identifies the most profitable assignment of planes to flight legs and through connections. The research team, led by James Orlin of the Massachusetts Institute of Technology and Ravindra Ahuja of the University of Florida, also developed the software for the model. United Airlines is adopting the mathematical model to improve the efficiency of flight scheduling and allow planning decisions within seconds. Previously, an airline's ability to assign flights in an integrated manner was impractical because of the large amounts of computer time needed. Using the more efficient software and mathematical model, the researchers estimate, could save the airline as much as $25 million annually. The researchers are now expanding the model to include additional criteria such as crew costs, reliability, and flexible flight departure times. [Amber Jones] -NSF-