Dr. Holly A. Stretz
Assistant Professor and AIChE Faculty Advisor

Contact Info:
Tennessee Tech University
Department of Chemical Engineering
Prescott Hall-Room 311
1020 Stadium Drive
Box 5013
Cookeville, TN 38505-0001
Phone: (931) 372.3495
Fax (931) 372.6352
E-mail:HStretz@tntech.edu

Nanocomposite structure and modeling • High temperature materials and ablatives • Polymer processing

Education

• Ph.D., Chemical Engineering, University of Texas, Austin, 2005
• M.S., Chemistry, Texas State University, 1996
• B.S., Chemistry, Texas A&M University, 1980

Honors and Awards

• Marion Johnson Society of Plastics Engineers Presidential Scholarship, 2003 -2005
• Outstanding Paper of Conference Award, SAMPE, 2003

Research Statement

Our group is interested in advanced high performance polymer nanocomposites: the processing, characterization and prediction of bulk properties. These materials are often used in extreme environments such as conditions found in rocket ablatives and fire. Materials comprised of polymer and nanoparticles, including montmorillonite clays, carbon nanotubes and synthetic silicates such as polyoligomeric silsesquioxanes (POSS), offer improvement over traditional composites in mechanical, barrier and thermal properties while maintaining specific gravity and optical clarity. To achieve this level of performance, one must achieve high levels of dispersion and maintain compatibility at the interface between polymer and reinforcing agent. Current research focuses on modeling the development of incompatible phases over long time frames at moderate to high temperatures in polymer-layered silicate nanocomposites, particularly for montmorillonite clays. We are also interested in the development and modeling of soft materials whose bulk mechanical properties are affected by order-disorder transitions at the nanoscale.

Recent Publications

H. A. Stretz, D. R. Paul, P. E. Cassidy, “Poly(styrene-co-acrylonitrile)/ montmorillonite organoclay mixtures: A model system for ABS nanocomposites,” Polymer, 46 (2005) 3818.

H. A. Stretz, D. R. Paul, R. Li, H. Keskkula, P. E. Cassidy, “Intercalation and Exfoliation Relationships in Melt-Processed Poly(styrene-co-acrylonitrile)/Montmorillonite Nanocomposites,” Polymer, 46 (2005) 2621.

H. A. Stretz, W. Wootan, P. E. Cassidy, J. H. Koo, “Effect of Exfoliation on Poly(styrene-co-acrylonitrile)/Montmorillonite Nanocomposite Flammability,” Polymers for Advanced Technology, 16 (2005) 1.

Koo, J. H., Pilato, L. A., Wissler, G., Cheng, J., Ho, D., Nguyen, K., Stretz, H., Luo, Z. P., “Flammability and Mechanical Properties of Nylon 11 Nanocomposites,” Proc. SAMPE 2005 ISEE, SAMPE, Covina, CA, 5-2005

S. Bourbigot, D. L. Vanderhart, J. W. Gilman, S. Bellayer, H. A. Stretz, D. R. Paul, “Solid State NMR Characterization and Flammability of Styrene-Acrylonitrile Copolymer /Montmorillonite Nanocomposites,” Polymer, 45 (2004) 7627-7638.