Genetically Directed Syntheses of New Polymeric Materials

California Institute Of Technology, Pasadena CA

Investigators

Abstract

The statistical nature of step and chain growth polymerization processes ensures that the products of such reactions must be heterogeneous. Conventional p9olymeric materials therefore consist of complex mixtures of chains, often characterized by broad distributions of chain length, sequence and stereochemistry. In many materials applications, this kind of molecular heterogeneity is acceptable, and in some applications it is advantageous, insofar as it may suppress crystallization and preserve desirable properties such as optical clarity, elasticity or ease of processing. On the other hand, synthetic developments that have afforded improved control of macromolecular architecture, such as Ziegler-Natta catalysis and living polymerization, have had profound impact on polymer science and technology. %%% Over the past decade, several laboratories - including the PI's - have exploited the capacity of the protein biosynthetic apparatus of bacterial cells to make new macromolecular materials characterized by essentially complete control of molecular architecture. The most important advantages of this method appear to lie in two areas: i). In the integration of material properties with biological function, and ii). In the design and fabrication of small-scale structures (sometimes called nanostructures), in which uniformity of molecular architecture is critical. This proposal addresses the latter objective, with a specific focus on the assembly behavior of systems containing monodisperse macromolecular rods related to poly (g-benzyl a,L-glutamate) (PBLG). This research is co-funded by the Polymers Program in the Division of Materials Research and the Molecular Biochemistry Program in the Division of Molecular and Cellular Biosciences. ***