CBE/ENGR 225 Faculty Seminar: Rachel Segalman, Ph.D. Edward Noble Kramer Professor Professor and Chair in Department of Chemical Engineering Professor in Department of Materials University of California, Santa Barbara
Rachel A. Segalman, Ph.D.
Edward Noble Kramer Professor
Professor and Chair in Department of Chemical Engineering
Professor in Department of Materials
University of California, Santa Barbara
Tuesday, April 12, 2016
ESB, Room #2001
*Cookies and Coffee will be provided*
Sequence: Where Polymer Physics Meets Polypeptoids
Chain shape and monomer sequence are two handles that affect polymer properties and selfassembly;
however, it is difficult to control these handles in conventional synthetic polymers without
also changing other factors, such as chemistry. Polypeptoids, a class of sequence-specific bioinspired
polymers, have a chain shape that can be tuned by the introduction of monomers with bulky chiral
aromatic side chains, allowing one to induce a helical conformation while preserving the chemical
nature of the side chains. Here, we examine the rigidity of polypeptoid helices using small angle
neutron scattering to measure the persistence length of both a helical and a non-helical peptoid chain.
Incorporation of these polypeptoids into block copolymers enables a systematic study of the effect of
chain shape on self-assembly while maintaining similar enthalpic interactions. Because both the
helical and non-helical peptoid blocks have similar flexibilities, it is shown that the strength of
segregation depends much more on monomer composition. These studies are a promising basis for
further examining the effect of monomer sequence control on block copolymer self-assembly. In this
talk, I will also discuss the use of this model system to understand the role of sequence on chain
collapse and globule formation in solution, polymer crystallization, and potential application as surface active agents for anti-fouling.