The Nelson W. Taylor Lecture Series in Materials Science and Engineering honors the memory of Professor Nelson W. Taylor (1869–1965) who was head of Penn State’s Department of Ceramics from 1933–1943. During his tenure as department head, Dr. Taylor refined the ceramics undergraduate curriculum, strengthened the graduate program, expanded ties with industry, and was able to attract important scientists (for example Woldemar A. Weyl) to the faculty. He is recognized as the individual most responsible for establishing the College of Earth and Mineral Sciences as a major center for ceramics research. The Nelson W. Taylor Lecture Series was established in 1969, and has consistently attracted scientists of international prominence.
2022 Keynote Speaker
Michael Rubinstein, Aleksandar S. Vesic Distinguished Professor, Professor of Mechanical Engineering and Materials Science, Biomedical Engineering, Chemistry, and Physics at Duke University.
“A-B associating polymer solutions and gels”
Polymer associations due to the formation of reversible bonds between different groups (A-B type) are qualitatively different from pairwise associations of the same groups (A-A type). The degree of conversion for A-B associations is lower than for A-A associations and depends on the stoichiometry of the associating groups. We predict re-entrant sol-gel-sol transitions for solutions of A-B associating polymers as functions of stoichiometry. Both A-B gelation and phase separation are suppressed relative to A-A solutions with phase diagrams for both dependent on solvent quality. Chemical incompatibility between A and B polymers results in competition between A-B association-induced attractive phase separation and incompatibility-driven repulsive phase separation. An example of A-B associating solutions is a coacervate of oppositely charged polyelectrolytes. Weak associations between oppositely charged polyelectrolytes (less than thermal energy kT per charge) with asymmetry of the polyanion and polycation line charge densities form double-semidilute solutions. Dynamics of higher charged polymers in these asymmetric coacervates are slower due to dynamic coupling between polyanions and polycations including reptation of higher charged polyelectrolytes along the confining tubes of lower charged polyelectrolytes. Strong associations with binding energy higher than thermal energy kT form reversible gels and, in the case of asymmetry of charge line density, these networks have bottlebrush or star-brush symmetry and unusual properties.
Michael Rubinstein received B.S. from Caltech in 1979 and Ph.D. in physics from Harvard University in 1983. After two years as a post-doc at AT&T Bell Laboratories, he joined Research Laboratories of Eastman Kodak Company where he worked for 10 years. In 1995 Michael Rubinstein started his academic career at the University of North Carolina at Chapel Hill and in 2018 he moved to Duke University where he is currently Aleksander S. Vesic Distinguished Professor of Departments of Mechanical Engineering and Materials Science, Biomedical Engineering, Physics, and Chemistry. In 2016 Rubinstein became a Distinguished Professor at Hokkaido University. In 2003 he published a textbook “Polymer Physics” with R. H. Colby. In 2010 he received the Polymer Physics Prize of the American Physical Society. In 2018 he received the Bingham Medal of the Society of Rheology and in 2019 the Soft Matter and Biophysical Chemistry Award of the Royal Society of Chemistry. Rubinstein is currently serving as the Chair of the IUPAP Working Group on Soft Matter.
Rubinstein’s research interests are in the area of soft condensed matter physics with an emphasis on polymer physics. His main scientific contributions include theories of polymer entanglements, dynamics of reversible networks, and models of charged polymers. His recent scientific interests are in applications of polymer physics to biological systems.
Enrique Gomez, Professor, Chemical Engineering and Materials Science and Engineering, Penn State
“Nanoscale control of density variations is crucial to optimize polymer membranes for water purification”
Reverse osmosis modules comprised of composite polymer membranes represent a leading technology in desalination and purification of brackish water. Nanoporous polymeric membranes are key for prefiltering of such reverse osmosis systems, as well as for purification of biopharmaceutical products, such as monoclonal antibodies. The field has relied on intricate control of membrane properties through systematic perturbations to membrane chemistries and processing, yet many fundamental questions remain on the mechanisms that govern water transport and separations. We have leveraged advances in multi-modal electron microscopy to generate new insights on membrane structure and function. For example, we have combined the focused ion beam with scanning electron microscopy through serial sectioning to reconstruct a 3D representation of ultrafiltration membranes using for virus removal from biopharmaceutical streams. In addition, we have combined energy-filtered transmission electron microscopy with electron tomography from scanning transmission electron microscopy images to map the variation in density of polyamide films used in reverse osmosis membranes. Quantitative analyses of imaging products are key to extract mechanistic details that govern water transport and separations. Furthermore, we image membranes challenged with model and common foulants, to ascertain initial conditions and mechanisms for degradation of filtration performance.
Enrique D. Gomez received a B.S. in Chemical Engineering from the University of Florida in 2002, received a Ph.D. in Chemical Engineering from the University of California, Berkeley in 2007, and spent a year and a half as a postdoctoral research associate at Princeton University. Dr. Gomez joined the faculty at the Pennsylvania State University in August of 2009, where he is now a Professor of Chemical Engineering and Materials Science and Engineering. He also serves as the Associate Head for Diversity, Equity and Inclusion in the Department of Materials Science and Engineering. Research activities of Dr. Gomez are focused on connecting the chemical structure soft materials to macroscopic properties. To this end, the Gomez group pushes the limits of X-ray scattering and electron microscopy to refine descriptions of the microstructure of soft materials. The current emphasis of his research group is on the relationship between microstructure and electrical properties in the active layers of organic thin film transistors and photovoltaics, on elucidating the key factors that govern aqueous transport through water filtration membranes, and in the development of microstructure control to enable sustainable materials. Enrique has received multiple awards, including a Visiting Scientist Fellowship from the National Center for Electron Microscopy, the Ralph E. Powe Junior Faculty Award by the Oak Ridge Associated Universities, the National Science Foundation CAREER Award, the Rustum and Della Roy Innovation in Materials Research Award, the Penn State Engineering Alumni Society Outstanding Research Award, and the Arthur K. Doolittle Award of the American Chemical Society. He was also elected Fellow of the American Physical Society in 2021.
Robert Hickey, Assistant Professor, Materials Science and Engineering, Penn State
“Hierarchically ordered block copolymer materials via nonequilibrium processing”
The diversity and vastness in the types of properties of living systems, including enhanced mechanical properties of skin and bone, or responsive optical properties derived from structural coloration, are a result of the multiscale, hierarchical structure of the materials. The field of materials chemistry has leveraged equilibrium concepts to create complex materials seen in nature, yet achieving the remarkable properties present in living systems requires moving beyond this formalism by utilizing nonequilibrium processes to create new and exciting materials. Here, the presentation will describe a new method to create hierarchically ordered, physically crosslinked hydrogels, and recent developments in further processing the hydrogel materials to create linear and rotary actuators. Specifically, we have explored a modified nonsolvent-induced phase separation method termed rapid injection processing to produce hierarchically ordered hydrogels with structures and mechanical properties resembling those of living biomaterials. The hydrogel fabrication process entails injecting a triblock copolymer, such as poly(styrene)-poly(ethylene oxide)-poly(styrene) (SOS), solution into a coagulating liquid (i.e., water), driving the hydrophobic polymer domains to organize at the nano and microscale and forming bulk hydrogels. We have established a universal and quantitative method for fabricating and controlling physically crosslinked hydrogels exhibiting hierarchical ordering by controlling the initial pre-injection triblock copolymer solution concentration and water-miscible organic solvent. Additionally, water-swollen hydrogel materials are easily processed to create high-performance linear and rotary actuators via strain-programmed hydrogel crystallization. The crystallized fibers display enhanced mechanical properties due to the aligned alternating amorphous and crystalline domains, and actuation is triggered using either water or heat. The work presented here highlights that by harnessing nonequilibrium methods, it is possible to create materials with tunable physical properties via controlling the structure from the nanometer to the micrometer.
Prof. Robert J. Hickey is currently an Assistant Professor in the Department of Materials Science and Engineering at The Pennsylvania State University. The Hickey group investigates equilibrium and non-equilibrium chemical and self-assembly methods to create functional, responsive, and multiscale polymeric materials. He received his B.S. and Ph.D. in Chemistry at Widener University (2007) and the University of Pennsylvania (2013), respectively. Before starting at Penn State in 2016, he was a postdoctoral researcher (2013-2016) at the University of Minnesota. As an assistant professor, Robert has been awarded the Air Force Office of Scientific Research Young Investigator Prize, the NSF CAREER Award, and was selected as a 2019 ACS PMSE Young Investigator.
Hee Jeung Oh, Assistant Professor, Chemical Engineering, Penn State
“3D printed biosponge polymers for capturing drugs before they spread through the body”
Due to longer life expectancies, the prevalence of age-related diseases is increasing rapidly, and the need for developing biomedical devices that can solve big health problems is similarly greater. Inspired by adsorption columns, which are routinely used in industry to remove pollutants from chemical streams, this research describes the design of biosponge polymers for capturing unwanted toxins in the body. One significant benefit of using polymer membranes is their tunable binding affinity to target molecules using specific chemical, physical, or biological features. One example is using properly designed biosponge polymers to remove cancer chemotherapy drugs that are not taken up by the target tumor during chemotherapy to reduce the drugs’ toxic side effects.
Cancer is becoming the leading cause of death in most developed nations. Despite efforts to develop targeted and personalized cancer therapeutics, dosing of the cancer chemotherapeutics is limited by toxic side effects. During intra-arterial chemotherapy infusion to a target organ, typically, more than 50-90% of the injected drug is not trapped in the target organ and bypasses the tumor to general circulation, causing toxicities in distant locations.
In the context of reducing the toxicity of chemotherapy, we have designed, built, and deployed porous biosponge polymer adsorbers for capturing chemotherapy drugs before they spread through the body. The porosity was obtained by 3D printing of lattice structures. The surface of porous cylinders was coated with an ion-containing nanostructured block polymer which is responsible for capturing doxorubicin, a widely used chemotherapy drug with significant toxic side effects. Using a swine model, our initial design enables the capture of 69 % of the administered drug without any adverse effects. Additional improvement may be obtained by changing the chemical composition of the selective membrane layer and controlling the lattice structure and size with elastomers.
Dr. Hee Jeung Oh is an Assistant Professor of Chemical Engineering at the Pennsylvania State University. The Oh research group studies the relationship between polymer chemistry, processing, structure, and transport properties for separation science. Specifically, the Oh lab explores the influence of polymer’s chemical and physical structures on transport properties such as sorption, diffusion, and permeation of small molecules in polymers and polymer-based materials. These fundamental studies are critical for membranes for liquid, gas and vapor separations, energy storage, selective removal of unwanted molecules from various chemical streams, biomedical devices, controlled drug-delivery, and barrier materials for food and packaging. Dr. Oh earned her bachelor’s degree in Chemical Engineering from the Korea Advanced Institute of Science and Technology (KAIST). Dr. Oh completed her graduate training in Chemical Engineering working in Profs. Benny Freeman’s and Donald Paul’s research groups at the University of Texas at Austin, exploring a variety of polymeric materials for membrane-based separation. Her postdoctoral training, working in Prof. Nitash Balsara’s research group at UC Berkeley, focuses on designing porous nanostructured polymers for energy storage, as well as for a new emerging biomedical application, “drug capture,” to minimize toxic side effects of cancer chemotherapy drugs. Dr. Oh has 16 peer-reviewed publications and two patents and has been recognized with several awards including the 3M Non-Tenured Faculty Award, Young Membrane Scientist Award from the North American Membrane Society (NAMS), and the University of Texas at Austin Professional Development Award.
Nelson W. Taylor Awardees
* Nobel Laureate
1970 John Saylor
1970 Horst Scholze
1971 Clarence Zener
1972 Gene Haertling
1973 Linus Pauling*
1974 Herman Mark
1975 Cyril Smith
1976 John A. Duffie
1977 Elburt E. Osborn
1978 Edward Teller
1979 Turner Alfrey, Jr.
1980 Morris Cohen
1981 Irving Wender
1982 W. Dave Kingery
1983 William O. Baker
1984 Pierre-Gilles de Gennes*
1985 Julian Szekely
1986 Paul B. Weisz
1987 David W. Johnson, Jr.
1988 Makoto Kikuchi
1989 Sir Samual Edwards
1990 Mats Hillert
1991 Richard Balzhiser
1993 Richard E. Smalley*
1994 Gerhard Wagner
1995 Thomas W. Eagar
1997 Larry L. Hench
1998 Alan G. MacDiarmid*
1999 John Price Hirth
2001 George Craford
2003 Charles M. Lieber
2004 Robert S. Langer
2005 Marvin L. Cohen
2006 Lawrence L. Kazmerski
2007 Timothy P. Lodge
2008 John B. Goodenough*
2009 Tobin J. Marks
2010 Chad A. Mirkin
2012 Subra Suresh
2013 P. M. Ajayan
2015 Thomas Kelly
2016 Shuji Nakamura*
2017 Jennifer Lewis
2018 Ramamoorthy Ramesh
2019 Giulia Galli
2020 Cato T. Laurencin