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Background
Judy Riffle received her Ph.D. in Polymer Chemistry from Virginia Tech in 1981. Following graduate school, she worked as a research chemist for Union Carbide Corporation, where her work was primarily centered on new methods and catalysts for preparing reactive polyether and polyester prepolymers and copolymers. She joined Thoratec Laboratories Corp., a cardiovascular biomaterials company specializing in polysiloxane copolymers and polyurethanes, in 1983 as manager of its Materials Division, and became Vice President of Research and Development in 1985. Dr. Riffle rejoined Virginia Tech as an Assistant Professor of Chemistry in 1988, where she now holds a tenured position as Professor. She has been active in the Polymer Division of the American Chemical Society for many years, having served in many positions including Chair of the Division in 1997.
RESEARCH INTERESTS
Ionic Ring-opening Polymerizations for Synthesis of Siloxane, Ether, Ester and Amide Oligomers and Block Copolymers
Dr. Riffle’s work on synthetic methods for functional polysiloxane oligomers, their incorporation into multiphase copolymers, and their transition into medical applications began during graduate school, continued into her industrial work, and remains an academic focus. Her understanding of polysiloxane redistribution reactions led to a broad range of telechelic oligomers suitable for incorporation as blocks into multiphase block copolymers. This later contributed greatly to the development of polydimethylsiloxane containing polyurethanes and ureas which are currently the basis of commercial artificial (bridge-to-transplant) hearts and vascular grafts, and to polysiloxane thermosets now marketed as extended-wear, soft, contact lenses.
Ring-opening polymerizations were extended from the polysiloxanes into cationic polymerizations of alkyloxazolines, and to lactone, lactide and epoxide reactions to prepare well-defined di- and tri-block multiphase copolymers from these structures. She collaborated with others to study these materials as emulsifiers for polymer blends and as steric stabilizers for inorganic oxide dispersions. One of the most important aspects of this collaborative work was to gain a multi-disciplinary understanding of some of the science underlying steric stabilization of dispersions.
Dr. Riffle’s current emphasis is on the synthesis of multiphase, di- and tri-block copolymer steric stabilizers, and on preparing nanoscale, superparamagnetic, biocompatible dispersions of these macromolecular magnetic particle complexes. Her work on magnetite fluids in polydimethylsiloxane carriers is currently being transitioned into clinical investigations for treating retinal detachments. Longer-term research in this area is devoted to understanding how to stabilize magnetic metal nanoparticle surfaces against oxidation, how to control nanoparticle size via macromolecular solution templates, and relating size and chemical structure of the complexes to magnetic properties.
EDUCATIONAL CONTRIBUTIONS
Professor Riffle’s educational contributions have included teaching courses in Organic Chemistry, Organic Chemistry of Polymers, Synthesis of Macromolecules, Technical Oral Communications, Laboratory in Polymer Science, Adhesive and Sealant Science, Fundamentals of Macromolecular Science and Engineering, Macromolecular Literature and Writing, and undergraduate and graduate research. Her contributions to continuing education have included instruction of 5-day Short Courses in polymer science to academic and industrial scientists and engineers: Principles and Practice of Polymers, Introduction to Adhesives and Composites, Polymer Synthesis, Design and Retrofit with Fiber Composites, Adhesion Science, and Polymers in Medicine and Biology. Dr. Riffle has led the initiation and growth of interdisciplinary, interdepartmental MS and PhD graduate degree programs in Macromolecular Science and Engineering (MACR) at Virginia Tech which began the first class in Fall, 2001, and she is the program’s Director. The program now comprises 58 graduate students. She is also the PI and Director of an NSF Integrated Graduate Education and Research Training (IGERT) educational initiative. This is an interdisciplinary, experimental education program integrating coursework, research and leadership training which encompasses students and faculty from the Departments of Chemistry, Chemical Engineering, Engineering Science and Mechanics, Civil and Environmental Engineering, Electrical and Computer Engineering, and Wood Science to train students in Macromolecular Science and Infrastructure Engineering.
Dr. Riffle has directed 21 PhD and 9 MS graduates, and 9 post-doctoral students. She currently mentors a group of 10 PhD students and 1 post-doctoral fellows. It may be noteworthy that 16 of the 30 graduate degrees earned by students under her direction have been conferred to women and 3 PhDs and 1 MS have been to women from underrepresented groups.
PROFESSIONAL ACTIVITIES AND CONTRIBUTIONS
Prof. Riffle is a member of the Division of Polymer Chemistry, Polymeric Materials: Science and Engineering Division, and the Rubber Divisions of the American Chemistry Society (ACS); and of the Society for the Advancement of Materials and Process Engineering. She has been highly active in the National ACS Division of Polymer Chemistry for many years: Her contributions to its executive board have been as Polymer Preprints Assoc. Ed., 1986-1991; National Programming Co-Chair, 1991-1995; 8th Int’l. Ring-Opening Symposium Chair, 1992; Div. Vice-Chair, 1995; Co-Chair, Nat’l Graduate Student Conference, 1995; Co-Chair MACRO Secretariat Conf. on Composites, 1995; Div. Chair-Elect, 1996; Div. Chair (by national election), 1997; Symposium on Polymeric Dispersions Chair, 1997; Div. Past-Chair, 1998; Nominations Chair, 1998; Long-term Planning Committee Chair, 1998; Nat’l Workshop Chair, 1998-present; Member of the Executive Committee in charge of Business Operations, 2002-present; co-Chair for the 4th International Workshop on Polymers in Medicine and Biology, ACS, 2005-present.
Dr. Riffle has served as a reviewer on numerous National Science Foundation review panels and for mail-reviewed proposals. She has served on other national committees including the National Materials Advisory Board Committee on Materials for Airframes, Engines, and Spacecraft (AFOSR), Chair of the Polymer Sect., 1998; NIST Advisory Committee for the Advanced Technology Program on Infrastructure, 1998; several ACS national award committees; the Civil Engineering Research Foundation subcommittee on Flame Retardant Materials, 1999; the National Research Council Committee on Fire Research, and National Institute of Health Study Group on Nanotechnology, 2006.