April 2, 2007 -- David Green, assistant professor of chemical engineering at U.Va., recently obtained a $400,000 National Science Foundation (NSF) Faculty Early Career Development (CAREER) grant for his breakthrough research in polymer nanocomposites.

The CAREER award is one of the most prestigious grants available to junior faculty members in science and engineering fields.  The grant provides resources to faculty who have demonstrated great potential early in their careers.

Polymers are characterized by their long, repeating chains of molecules.  They are both naturally occurring—such as DNA, or human-made—such as plastic.  Polymeric materials are engineered by adding different types of particles to polymers in order to produce new materials that exhibit the best properties of both.  This area of research is significant.  Manufacturing industries would greatly benefit from having more control over material properties such as strength and weight.  In addition, it is typically more cost effective to create composite materials.  Yet much is still unknown about the fundamentals of engineering them.  “Research in this area for the most part has been done in a very ad hoc way,” says Green.

Green’s CAREER grant will allow him to explore a largely uncharted area of chemical and materials engineering.  He will experimentally and theoretically examine the impact of grafting polymer chains to nanoparticles.  Green’s lab is proficient in synthesizing nanoparticles from scratch, changing their properties, and predicting their dispersion.  In grafting polymer chains to these nanoparticles, Green aims to control particle dispersion in concentrated polymer solutions and melts, the starting materials for polymer nanocomposites.  Since particle aggregation tends to erode material properties, fine control over the behavior of grafted polymers should prevent aggregation, optimizing material characteristics.  Ultimately, using responsive grafted polymers to control the spacing between nanoparticles should lead to the creation of new composite materials that have enhanced mechanical, thermal, optical, and electrical properties.  The results of this research should have countless practical implications and improvements for everyday items such as biomedical gowns, diapers, tires, and paints.

The CAREER program requires that awardees find a way to integrate their research and teaching.  Green recognizes the importance of this, and will use his grant to address the lack of diversity in the engineering workforce.  Green notes that increasing the number of minorities and women who hold Ph.D.’s is critical for the long-term vitality of the science and engineering fields.  He will take advantage of an existing U.Va. resource—the Center for Diversity in Engineering to make headway towards this goal.  Through the Center’s U.Va. Research Experience for Undergraduates program, third years will have an opportunity to conduct hands-on research in Green’s lab.  In addition, Green will expose secondary teachers to the capabilities of his cutting edge lab through the Research Experience for Teachers  program.  “My ultimate goal is to create a pipeline of minority students who can excel in undergraduate work and then go on to graduate study in chemical engineering,” he says.