Dr. Julianne Harmon
Office: BSF 312, SCA 403
Phone: (813) 974-3397
Lab: BSF 357, 359
B.A., Mercyhurst College, 1971
M.S., Duquesne University, 1973
Ph.D., University of Rochester, 1983
Our research philosophy centers on the premise that applied research is most effective when it is basic in nature. In past years scientists often distinguished between basic and applied research. A more current line of thinking stresses the point that scientists are accountable to society to interface with industry in an effort to focus their basic understanding of scientific principles on the pertinent needs of society.
We have several exciting areas of research in our laboratories, including: high performance polymer composites with increased resistance to different types of radiation, optically transparent polymer/carbon nanotube composites with enhanced mechanical properties, polymer composites with high thermal conductivity, polymer nanocomposites that exhibit magnetic properties and new biocompatible composites based on hydrophilic polymers.
Our group has made important advances in carbon nanotube composite research. The goal of this research is to use carbon nanotubes as radiation sinks, dissipating energy and decreasing the frequency of radiolysis events. Most recently, progress has been made in solubilizing carbon nanotubes in polymer matrices. Optically transparent polymer composites with increased radiation resistance have been designed and tested and analyzed. This research resulted in two patent applications:
Harmon, J. P., Clayton, L., and Muisener, P., USF Invention Disclosure, "Transparent Polymer Nanotube Composites, "USF Ref No: 01B100, December 2001. Patent pending.
Harmon, J. P., Muisener, P., Clayton, L., and D'Angelo, J., USF Invention Disclosure, "Ionizing Radiation Resistant Carbon Nanotube/Polymer Composites", USF Ref. No. 01B090, December, 2001. Patent pending.
Another area of research in our group focuses on interaction of polymeric materials and highly energetic heavy atoms that are known to be part of Galactic Cosmic Radiation (GCR). A biological effectiveness (amount of damage) of the heavy ions consists of two major parts: a) energy transferred by a heavy particle along its trajectory, b) secondary radiation effects due to the nuclear interactions of incoming particles with shield material. Shield materials composed of atoms with small atomic mass (small number of inner shell electrons) have lower possibility of induced X-ray radiation as well as fewer neutrons to release during the nuclear interactions. Polymers consisting of only small atomic weight atoms (carbon, hydrogen) are considered to be promising materials for the production of GCR shields. Our group is in the process of developing new polymer nanocomposites that will show an enhanced resistance to GCR.
A new area of research is concerned with formulation, modification and characterization of biocompatible coatings. Certain hydrogels, due to their high biocompatibility, have been used in biomedical field as contact lens materials, bioadhesives, artificial tissue and implantable devices. The group is now engaged in synthesis and characterization of novel block-copolymer based hydrogel systems.
An important area of research in our group deals with optical fiber materials. This includes developing fiber core and cladding materials with controlled refractive indexes. One project focuses on designing polymeric core materials that are transparent in the near IR region of the electromagnetic spectrum. Another project involves the design in transparent, low refractive index cladding materials. In addition to stringent optical and mechanical criterion, the effect of ionizing radiation on optical and mechanical properties of these materials is also characterized. This work is applicable to space environments and to particle accelerators where scintillating optical fibers are used. Research involves collaborations with Optical Polymer Research Inc. and Honeywell Space Systems Group.
We have developed expertise in structure-property relations of dendrimers. Dendritic structures currently dominate the field of macromolecular chemistry in hopes that they will meet the need of the 21st century. Applications are found in drug therapy, polymer rheology modification and in nonlinear optical devices. Surprisingly, very little work has been done on characterizing these molecules by dielectric analysis. Our group has performed one of the first known dielectric analyses on neat, dendrimer molecules. These molecules exhibit relaxation phenomenon similar to those of linear macromolecules, exhibiting WLF behavior for the glass transition region and Arrhenius behavior for secondary relaxations. This is an area of expanding interest for our group.