Abstract
After a brief overview of the Macromolecules and Interfaces Institute (MII) at Virginia Tech, this lecture will focus on two distinctly different research topics in the Turner group: 1) the copolymerization of stilbene derivatives to new classes of rigid polyampholytes and rod-coil block copolymers, and 2) two different projects to molecularly engineer a high performance thermoplastic, polysulfone for enhanced performance.
The polymerization of 1,2-disubstituted monomers has always been problematic and the poly(phenylmethylene) backbone structure, prepared from the polymerization of stilbene, is unknown. Such polymers should have interesting rod-like behavior. Numerous substituted stilbene derivatives are known in the literature and are readily accessible synthetically so functional group containing rod-like copolymers would be made available from such structures. We are pursuing both the “homo” polymer of stilbene and functionalized copolymers. Using “donor-acceptor” alternating copolymerization of substituted stilbene monomers, novel highly functional rod-like copolymers have been synthesized and characterized by SEC, TGA and DSC. With 4,4’-dialkylaminostilbene as the donor and maleic anhydride as the acceptor, the solubility of the alternating copolymers in organic solvents is strongly affected by the length of the alkyl substituents on the amino groups. The water solubility of these alternating copolymers is pH dependent. Living radical processes can be applied to these alternating copolymers to yield rod-coil structures which appear to have unique self-assembly characteristics.
The melt flow characteristics of engineering plastics are extremely important in the processing of high performance polymers like polysulfones into useful parts. One recent patent claims the attachment of bulky dendritic structures to the terminal ends of thermoplastics leads to significant lowering of the low shear melt viscosity with minimal depression of the Tg. We have prepared a series of polysulfones that are terminated with aryl ether ketone dendrons. Recent physical characterization results indicate that these unique polymers show significant shear thinning without negatively impacting the mechanical properties.
Processing requirements for flexible displays and solar cells are not met by current semicrystalline thermoplastic polymers (PET and PEN) that can be extruded into performance films because of thermal deformation at the temperatures needed for optimal device fabrication. Our objective is to modify high Tg amorphous polysulfone with the incorporation of linear monomers to enhance crystallization so that these polymers can be biaxially oriented into films with enhanced resistance to thermal induced flow.
Biography
S. Richard Turner is currently the Director of the Macromolecules and Interfaces Institute and a Research Professor in the Department of Chemistry at Virginia Tech. He retired as a Research Fellow at Eastman Chemical Company in Kingsport, TN in December of 2004 to accept this position. A native of Nashville, TN he received his undergraduate training in chemistry at Tennessee Tech. He obtained his Ph.D. in organic polymer chemistry from the University of Florida in 1971 (with G.B. Butler) and spent one year as a post doc in polymer chemistry in Darmstadt, Germany (with R.C. Schulz). After working in the corporate research labs of Xerox and Exxon, he joined the Research Laboratories of the Eastman Kodak Company in 1982 and transferred to the Eastman Chemical Company in Kingsport in 1993. During his industrial polymer research career he has had the opportunity to be involved in a broad range of polymer research topics, both fundamental and applied, including: photoconducting polymers, water soluble polymers, ionomers, microresists, living radical polymerizations, dendritic/hyperbranched polymers, and high performance polyesters.
Richard was a member of the Advisory Board of the Petroleum Research Fund of the ACS from 1999 to 2005 and has served on several NSF review panels. He was a member of the industrial advisory board for the Department of Chemistry of the University of Florida and currently serves on the scientific advisory board for KensaGroup and Novomer, Inc. He has served on the editorial board of several journals and is currently an editorial board member for Journal of Polymer Science—Part A: Polymer Chemistry and Polymer Reviews. He was named the Americas Editor of Chemistry and Synthesis for POLYMER in 2005. He holds over 100 patents and has over 80 publications in various areas of polymer chemistry. He was a CUMIRP lecturer at UMass in 1990 and presented the Stein-Bayer lecture at UMass in 2002. He received a Distinguished Inventor’s Award from Eastman Kodak in 1993. In 2004 he was named an alumnus of the year at Tennessee Tech, received the University of Florida College of Liberal Arts and Sciences Chemistry Department outstanding alumni award, and was named as one of Tennessee’s Top Ten Scientists by Business Tennessee magazine. He received the “Speaker of the Year” award from the Northeast Tennessee section of the ACS in 2005.
Richard has been active in various functions in the Division of Polymeric Materials: Science and Engineering (PMSE) of the American Chemical Society. He served as PMSE Chairman in 1992. During his tenure as chairman PMSE established the Cooperative Research Award endowed by the Eastman Kodak Company and the Distinguished Service Award. Richard was also General Secretary of the Macromolecular Secretariat in 1995 and was the PMSE representative to the Secretariat for almost ten years. He was named a PMSE Fellow in 2002 and received the PMSE Distinguished Service Award in 2006.
Richard currently has a research group of seven Ph.D. students involved in the synthesis and properties of several different polymer systems including: novel functional and responsive polymers based on rigid polyampholytes and polyelectrolytes, polymeric antimicrobial materials, and engineering plastics with enhanced properties such as flow, controlled crystallinity, and environmental stability
