Timothy Long

Professor

Polymer Chemistry

Research Interests

Our research goal is to integrate fundamental research in novel macromolecular structure and polymerization processes with the development of high performance macromolecules for advanced technologies. Our research platforms focus on the design, performance, and societal implications of novel biomaterials for the following global impact: (1) gene/drug delivery, (2) tissue regeneration, and (3) biomedical devices. Our hypothesis states that biomaterial design involves fundamental and common structural parameters for performance and that the integration of biomaterials in various biological environments will involve common interfacial and performance challenges.

The development of efficient, nontoxic materials for the delivery of therapeutic nucleic acids and drugs is a fundamental and important problem in biotechnology research. For example, while many drugs are available to control cardiovascular disease (a leading global health problem), drug toxicity and lack of specificity leads to serious side effects. Delivery vehicles have the potential to minimize side effects while maximizing medicinal efficacy, yet fundamental studies on biomaterials-based delivery systems are severely lacking. Our research team focuses on the development and study of water-soluble polycations, particularly segmented block copolymer structures, for the binding, encapsulation, and delivery of anionic drugs and nucleic acids into cultured cells. We are currently examining structure-property effects of incorporating different cationic groups into these structures such as histidine-mimics and quaternary ammonium and phosphonium groups, and investigate the influence of nucleobase substitution in vector design, which may lead to novel binding strategies.

The tissue regeneration biotechnology seeks to replace failing organs, as opposed to treating the symptoms of underlying disease, functional restoration, improving quality of life. Our research builds on the discovery in the Long laboratories to fabricate nanometer-scale scaffolds based on nature-derived phospholipids and new families of photo-reactive amphiphiles.

Novel biomaterials that can transform the functionality and efficacy of medical devices and offer sustainable treatments with reduced cost are sought throughout the world to improve the quality of life. Recent efforts in our laboratories are focused on biomaterials for stents for sensing force needed to employ a device and also the incidence of tissue re-growth near the device interface with biological structure (Vlachos, Long) and biomaterial alternatives to acid-generation during polylactide absorption. Research efforts are proposed based on the synthesis and characterization of charged polyurethanes for subsequent performance as an elastomeric electromechanical transducer.

In addition to macromolecular chemistry and engineering at the interface with biology, our research group also addresses fundamental questions involving ionic liquids, charged polymers for electroactive devices, fuel cell membranes, novel adhesives, block copolymer elastomers, high impact engineering thermoplastics, and responsive polymer compositions based on tailored hydrogen bonding and electrostatic interactions. Recent efforts in self-healing compositions offer promise for novel families of cationic polymers.

1. Long, T.E., Reaction: Benign by Design Demands Innovation. Chem 2017, 2(1), 7-8. http://www.sciencedirect.com/science/article/pii/S245192941630242X

2. Nelson, A.; Pekkanen, A.; Forsythe, N.; Herlihy, J.; Zhang, M.; Long, T., Synthesis of Water Soluble Imidazolium Polyesters as Potential Non-viral Gene Delivery Vehicles. Biomacromolecules 2016, In-Press. http://pubs.acs.org/doi/abs/10.1021/acs.biomac.6b01316

3. Zhang, K.; Talley, S. J.; Yu, Y. P.; Moore, R. B.; Murayama, M.; Long, T. E., Influence of nucleobase stoichiometry on the self-​assembly of ABC triblock copolymers. Chemical Communications 2016, 52(48), 7564-7567. http://pubs.rsc.org/is/content/articlehtml/2016/cc/c6cc03502g

4. Zhang, K.; Nelson, A. M.; Talley, S. J.; Chen, M.; Margaretta, E.; Hudson, A. G.; Moore, R. B.; Long, T. E., Non-​isocyanate poly(amide-​hydroxyurethane)​s from sustainable resources. Green Chemistry 2016, 18, 4667-4681. http://pubs.rsc.org/is/content/articlehtml/2016/gc/c6gc01096b

5. Jangu, C.; Schultz, A. R.; Wall, C. E.; Esker, A. R.; Long, T. E., Diphenylphosphino Styrene-​Containing Homopolymers: Influence of Alkylation and Mobile Anions on Physical Properties. Macromolecular Rapid Communications 2016, 37, 1212-1217. http://onlinelibrary.wiley.com/doi/10.1002/marc.201600037/full

  • Named an AAAS Fellow, 2016
  • Virginia Outstanding Scientist of the Year, 2015
  • Robert L. Patrick Fellowship Award, 2014
  • Regional Chair, IUPAC World Polymer Congress, MACRO 2012 at Virginia Tech, June 2012
  • Inducted into the ACS Polymer Division Fellows program, 2012
  • Mark Scholar Award, 2012
  • Pressure Sensitive tape Council, Carl Dahlquist Award, 2012
  • PMSE Cooperative Research Award, 2011
  • Virginia Tech Alumni Award for Research Excellence for 2010
  • American Chemical Society Fellow, 2009
  • Elected Chair, Polymers Gordon Research Conference (GRC), summer 2009
  • Invited Wake Forest University, Affiliated Professor of the WFIRM Wake Forest Institute for Regenerative Medicine (2008)
  • Chair-elect, 2012 Polycondensation Conference (2008)
  • Symposium Co-chair, 2012 IUPAC World Polymer Congress (2008)
  • IRTF Interdisciplinary Research Team Fellowship Award, with Profs. Duncan and Thatcher
  • Collano Innovation Award, Lucerne, Switzerland - September 2006
  • Chair-elect, 2009 Polymers (East) Gordon Research Conference (2005)
  • Chair, ACS Division of Polymer Chemistry (2005)
  • Faculty Research Award, Department of Chemistry (May 2003)
  • Top Oral Presentation, ASI USER FORUM, June 2002 ($2000 award)
  • ACS, Division of Polymer Chemistry, Chair-elect, 2002-2005
  • IBM Faculty Award, 2002
  • 3M Company Faculty Award, 2000-2001
  • B.S. Chemistry, St. Bonaventure University, 1983
  • Ph.D. Chemistry, Virginia Tech 1987
  • Director, Macromolecules Innovation Institute, 2014–present
  • Associate Dean for Research and International Outreach, VT College of Science, 2011–2014
  • Associate Director of Interdisciplinary Research and Education, Fralin Life Sciences Institute, Virginia Tech, 2009
  • Principal Research Chemist, Eastman Chemical Company, Kingsport, TN, 1993
  • Advanced Technical Program Researcher (ATP, sponsored by NIST), 1991
  • Senior Research Scientist, Eastman Kodak Company, Rochester, NY, 1990
  • Advanced Research Scientist, Eastman Kodak Company, Rochester, NY, 1987
Timothy Long

Contact

Email: telong@vt.edu
Office: 313F Davidson Hall
Phone: 540-231-2480
Group Website: http://www.tlong.chem.vt.edu/

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