Nanotechnology makes it easy to be green

man smilingIt's easy being green. At least it is for Lawrence Drzal, university distinguished professor of chemical engineering and materials science and director of the Composite Materials and Structures Center, and his colleagues Amar Kumar Mohanty, associate professor of packaging; Manjusri Misra, visiting associate professor in the Composite Materials and Structures Center; Bruce Dale, professor of chemical engineering and materials science; and Farhang Pourboghrat, associate professor of mechanical engineering. The researchers are working to develop biobased composite and nanocomposite materials, providing a foundation for the next generation of environmentally friendly structural materials.

The United States uses 80 million tons of petroleum per year to manufacture plastics. Drzal and his colleagues want to change that.

In a project supported by the Environmental Protection Agency, the MSU team expects to generate "green" nanocomposite materials for use in the auto industry by combining nanoclay with bacterial bioplastic (known as polyhydroxyalkanoates or PHA). PHA bioplastic is the only water-resistant plastic made from renewable resources that has potential for automotive applications.

Another project, funded by the National Science Foundation, is investigating the environmental impact of processing and manufacturing green composites from engineered plant biofibers and PHA bioplastic and corn-derived polylactides for use in automotive and other industries.

Drzal's lab also has discovered a new nanomaterial: exfoliated nanographite platelets. With the collaboration of industry sponsors General Motors, Metabolix, Natureworks, Flaxcraft, Nanocor and T/J Technologies, Drzal is studying whether the platelets can be added to bioplastics to make the resulting biobased nanocomposite materials multifunctional. So far, adding a small amount of platelets to the bioplastics has made the bionanocomposites stiffer, stronger, tougher and more scratch-resistant, and improved their electrical and thermal conductivity -- very desirable traits in composite materials.

Biocomposite materials, Drzal said, have several advantages. They're made from renewable products, not petroleum. The cost for biocomposite materials can be reduced with large-scale usage. And their biodegradability could eliminate potentially harmful effects related to materials processing and disposal.