MACROMOLECULAR SCIENCE AND ENGINEERING

LEI ZHU

Research Interests

Nanoscale structure and morphology of crystalline/liquid crystalline polymers and block copolymers; ferroelectric and dielectric polymers for electric energy storage; polymer/inorganic hybrid nanocomposites; biodegradable polymers for diagnostic and drug delivery.

Overview of Research

Our research mainly focuses on polymer ordering at nanoscales. Here, polymer ordering refers to polymer crystallization, liquid crystal formation, and block copolymer self-assembly. Our goal is to connect information on polymer structure and morphology at nanoscales to unique electrical, optical, and biological properties for both energy and health applications. To pursue this goal, our research is steered into the following directions; 1) Nanoconfined polymer ferroelectricity and its applications in high energy storage; 2) Polymer/inorganic nanocomposites for advanced electrical, optical, and barrier properties; 3) Biodegradable block copolymers and dendrimer-like star polymers (DLSPs) as novel nanobiomaterials for diagnostic and medicinal applications; 4) Polymeric Janus nanoparticles and their self-assembly.

Current Activity

Our current research activity includes the following four main thrust topics:

1. Nanoconfined ferroelectric polymers and their applications in high electric energy storage;
2. Polymer-coated inorganic nanoparticles and their nanocomposites;
3. Multivalent aptamer-DLSP conjugate nanomaterials as artificial antibody;
4. Polymeric Janus nanoparticles and their self-assembly in solvents.

For details, please refer to our group webpage.

Recent Publications

1. Zhu, L.*; Wang, Q.* Novel ferroelectric polymers for high energy density and low loss dielectrics.Macromolecules 2012, 45, doi: 10.1021/ma2024057.
2. Mackey, M.; Flandin, L.; Schulele, D.; Zhu, L.*; Wolak, M.; Shirk, J.; Hiltner, A.; Baer, E.* Reduction of dielectric hysteresis in multilayered film via nanoconfinement. Macromolecules 2012, 45, doi: 10.1021/ma202267r.
3. Su, R.; Tseng, J.-K.; Lu, M.-S.; Lin, M.; Fu, Q.; Zhu, L.* Ferroelectric behavior in the high temperature paraelectric phase in a poly(vinylidene fluoride-co-trifluoroethylene) random copolymer. Polymer 2012, 53, 728-739.
4. Zhong, G.; Wang, K.; Zhang, L.; Li, Z.-M.; Fong, H.*; Zhu, L.* Nanodroplet formation and exclusive homogenously nucleated crystallization in confined electrospun immiscible polymer blend fibers of polystyrene and poly(ethylene oxide). Polymer 2011, 52, 5397-5402.
5. Pan, M.*; Yang, L.; Guan, B.*; Zhong, G.; Zhu, L.* Surface nucleation-induced fluoropolymer Janus nanoparticles via emulsifier-free batch-seeded emulsion polymerization. Soft Matter 2011, 7, 11187-11193.
6. Wu, S.; Lin, M.; Lu. S. G.; Zhu, L.; Zhang, Q. M.* Polar-fluoropolymer blends with tailorednanostructures for high energy density low loss capacitor applications. Appl. Phys. Lett. 2011, 99, 132901.
7. Wang, Q.; Zhu, L. Polymer nanocomposites for electric energy storage. J. Polym. Sci., Part B: Polym. Phys. 2011, 49, 1421-1429.
8. Guan, F.; Wang, J.; Pan, J.; Wang, Q.; Zhu, L.* Effects of film processing conditions on electric energy storage for pulsed power applications. IEEE Dielectr. Electr. Insul. 2011, 18, 1293-1300.
9. Guan, F.; Wang, J.; Yang, L.; Guan, B.; Han, K.; Wang, Q.; Zhu, L.* Confined ferroelectric properties in poly(vinylidene fluoride-co-chlorotrifluoroethylene)-graft-polystyrene graft copolymers for electric energy storage applications. Adv. Funct. Mater. 2011, 21, 3176-3188.
10. Cao, W.; Zhou, J.; Mann, A.; Wang, Y.*; Zhu, L.* Folate-functionalized unimolecular micelles based on a degradable amphiphilic dendrimer-like star polymer for cancer cell-targeted drug delivery. Biomacromolecules 2011, 12, 2697-2707.
11. Guo, J.; Zhu, L.; Jiang, M.; Chen, D.* Deliberately designed processes to physically tether the carboxyl groups of poly(pentacosadiynoic acid) to poly (vinyl alcohol) glassy matrix to make poly(pentacosadiynoic acid) thermochromically reversible in the matrix. Langmuir 2011, 27, 6651-6660.
12. Wang, Y.; Yang, G.; Tang, P.*; Qiu, F.; Yang, Y.; Zhu, L. Mixed homopolymer brushes grafted onto a sphere. J. Chem. Phys. 2011, 134, 134903.
13. Zhong, G.; Zhang, L.; Su, R.; Wang, K.; Fong, H.*; Zhu, L.* Understanding polymorphism formation in electrospun fibers of immiscible poly(vinylidene fluoride) blends. Polymer 2011, 52, 2228-2237.
14. Guan, F.; Wang, J.; Yang, L.; Tseng, J.-K.; Han, K.; Wang, Q.; Zhu, L.* Confinement-induced high field antiferroelectric-like behavior in a poly(vinylidene fluoride-co-trifluoroethylene-co-chlorotrifluoroethylene)-graft-polystyrene graft copolymer. Macromolecules 2011, 44, 2190-2199.
15. Cao, W.; Zhu, L.* Synthesis and unimolecular micelles of amphiphilic dendrimer-like star polymer with various functional surface groups. Macromolecules 2011, 44, 1500-1512.
16. Lai, C.; Zhong, G.; Yue, Z.; Chen, G.; Zhang, L.; Vakili, A.; Wang, Y.; Zhu, L.*; Liu, J.*; Fong, H.*Investigation of post-spinning stretching process on morphological, structural, and mechanical properties of electrospun polyacrylonitrile copolymer nanofibers. Polymer 2011, 52, 519-528.
17. Guan, F.; Wang, J.; Pan, J.; Wang, Q.; Zhu, L.* Time and poling history dependent energy storage and discharge behaviors in poly(vinylidene fluoride-co-hexafluoropropylene) random copolymers. Chin. J. Polym. Sci. 2011, 29, 65-80.
18. Cao, W.; Zhou, J.; Wang, Y.*; Zhu, L.* Synthesis and in-vitro cancer cell targeting of folate-functionalized biodegradable amphiphilic dendrimer-like star polymers. Biomacromolecules 2010, 11, 3680-3687.
19. Jiang, X.; Zhao, B.*; Zhong, G.; Jin, N.; Horton, J. M.; Zhu, L.; Hafner, R. S.; Lodge, T. P. Microphase separation of high grafting density asymmetric mixed homopolymer brushes on silica particles. Macromolecules 2010, 43, 8209–8217.
20. Guan, F.; Wang, J.; Pan, J.; Wang, Q.; Zhu, L.* Effects of polymorphism and crystallite size on dipole reorientation in poly(vinylidene fluoride) and its random copolymers. Macromolecules 2010, 43, 6739-6748.
21. Jiang, X.; Zhong, G.; Horton, J. M.; Jin, N.; Zhu, L.; Zhao, B.* Evolution of phase morphology of mixed poly(t-butyl acrylate)/polystyrene brushes grafted on silica particles with the change of chain length disparity. Macromolecules 2010, 43, 5387–5395.
22. Miao, J.; Zhu, L.* Hydrogen bonding induced supramolecular self-Assembly of linear doubly discotic triad supermolecules. Chem. Asian J. 2010, 5, 1634-1641.
23. Miao, J.; Zhu, L.* Columnar liquid crystalline assembly of doubly discotic supermolecules based on tetra-triphenylene-substituted phthalocyanine. Soft Matter 2010, 6, 2072-2079.
24. Miao, J.; Zhu, L.* Topology controlled supramolecular self-assembly of octa triphenylene-substituted polyhedral oligomeric silsesquioxane (POSS) hybrid supermolecules. J. Phys. Chem. B 2010, 114, 1879–1887.
25. Miao, J.; Zhu, L.* Hydrogen bond-assisted supramolecular assembly of doubly discotic supermolecules based on porphyrin and triphenylene. Chem. Mater. 2010, 22, 197-206.
26. Guan, F.; Pan, J.; Wang, J.; Wang, Q.; Zhu, L.* Crystal orientation effect on electric energy storage in poly(vinylidene fluoride-co-hexafluoropropylene) copolymers. Macromolecules 2010, 43, 384-392.
27. Zhao, B.*; Zhu, L. Mixed polymer brush-grafted particles: A new class of environmentally responsive nanostructured materials. Macromolecules 2009, 42, 9369-9383 (persective article).
28. Cheng, F.; Zhang, K.; Chen, D.*; Zhu, L.*; Jiang, M. Self-assembly of heteroarm core-shell polymeric nanoparticles (HCPNs) and templated synthesis of gold nanoparticle clusters within HCPNS and the Superparticles. Macromolecules 2009,42, 7108-7113.
29. Guan, F.; Yuan, Z.; Shu, E. W.; Zhu, L.* Fast discharge speed in poly(vinylidene fluoride) graft copolymer dielectric films achieved by confined ferroelectricity. Appl. Phys. Lett.2009, 94, 052907.

Recent Presentations

Presented over 100 public lectures/seminars at national and international meetings, workshops, companies, or other universities.

Awards

Polymer Program Director's Award for Faculty Excellence, 2008
Rogers Teaching Excellence Award, 2005
DuPont Young Professor Award, 2005
3M Nontenured Faculty Award, 2004
NSF CAREER Award, 2004
Gencorp University Signature Award for Outstanding Academic and Research Work, 1999