Dr. Holly A. Stretz
Assistant Professor and Curriculum Coordinator

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 • Fate and transformation of nanoparticles in surface waters • Novel hydrogel nanocomposites for medical diagnostics

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

• TTU Sigma Xi Outstanding Research Award, 2009
• TTU College of Engineering Kinslow Award, 2007
• 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 interfacial compatibility and/or form interparticle connectivity. Current research focuses on formation of novel morphologies/networks of montmorillonite and other model nanoparticles (CdSe) which lead to optimized erosion performance. Another thrust is to utilize dispersion to form nanochannels in hydrogels used in medical diagnostics.  A third area of research is to understand environmental fate and transformation of metal nanoparticles such as gold or silver in surface waters.

Recent Publications

V. Pallem, H. A. Stretz, M. J. Wells, “Evaluating Aggregation of Gold Nanoparticles and Humic Substances Using Fluorescence Spectroscopy,” Environmental Science and Technology, submitted 2009.

J. W. Thompson, H. A. Stretz, P. E. Arce, “Thermoresponsive Microparticle Hydrogels,” US  12/275,253, WO 2009/067666 A2. 05-28-2009,Tennessee Technological University.

H. A. Stretz, N. Palla, “Modulus-based Scaling Parameter for Process Control of Exfoliation Efficiency in Nanocomposite Melt Compounding,” SAMPE Fall Technical Conference, Memphis, TN, 09-08-2008.

P. S. Bhosale, H. A. Stretz, “Gold Nanoparticle Deposition Using CO2-Expanded Liquids, Effect of Pressure Oscillation and Surface-Particle Interactions,” Langmuir 24 (2008) 12241-12246.

P. S. Bhosale, M. V. Panchagnula, H. A. Stretz, “Mechanically Robust Nanoparticle Stabilized Liquid Marbles,” Applied Physics Letters, 93 (2008) 034109.

H. A. Stretz, D. R. Paul, “Properties and Morphology of Nanocomposites Based on Styrenic Polymers: Part II. Effects of Maleic Anhydride Units” Polymer 47 (2006) 8527-8535.