“Soft Material Design at the Interfaces with Catalysis and Biology”

Professor Zhibin Guan

Department of Chemistry

1102 Natural Sciences II

University of California

Irvine, CA 92697-2025, USA

Email: zguan@uci.edu

Phone: 949 824-5172

http://www.chem.uci.edu/people/faculty/zguan/

Our research is centered on the design of new polymeric materials at two interfaces: one with catalysis and the other with biology. In this presentation, I’ll first provide a quick overview of our efforts at the catalysis interface. Our efforts at this interface are focused on the development of efficient catalytic synthesis of soft nanomaterials. By using late-transition-metal chain walking catalysts, we can synthesize functional dendritic nanoparticles directly from very simple olefin monomers. The second part of the talk will be focused on our recent results at the second interface area: new biomimetic polymer synthesis. Inspiration from natural biopolymers is used in our lab to design macromolecular materials having precise secondary structures for advanced mechanical properties. Modular domain structures are commonly seen in natural biopolymers such as adhesion proteins and skeletal muscle protein, titin, which assume important mechanical functions in biological systems. The remarkable combined strength and toughness of titin was proposed to derive from its modular structure comprising a linear array of domains, in which each domain is held together by secondary forces.  We have synthesized a number of titin-mimicking modular polymers having multiple domain structures. Single molecule experiments revealed sequential unfolding of the loops on a polymer chain. This talk will discuss the design principle, synthesis, single molecule studies, and correlation of single molecule and macroscopic mechanical properties of the modular polymer.