Title

Surface initiated polymerizations utilizing organometallic catalysts

Date of Completion

January 2000

Keywords

Chemistry, Organic|Chemistry, Polymer

Degree

Ph.D.

Abstract

A system for producing organic-inorganic nanocomposites of precisely tailored dimensions has been developed. The inorganic core consists of a gold particle whose diameter can be systematically varied from about 2 to 20 nm, and is passivated by an alkanethiol monolayer. A transition metal catalyst is ligated to an appropriate functionality incorporated into the alkanethiol monolayer, and a polymeric coating is formed through a surface bound catalyst. The polymerization reaction is spectroscopically monitored in real-time, and is terminated when a desired quantity of polymer has been produced. This system allows the manipulation of the sizes of the inorganic core and of the polymeric coating through several orders of magnitude, so that a nanocomposite can be rationally designed, then precisely produced. The sizes of the resultant structures have been characterized by transmission electron microscopy, dynamic light scattering, thermogravimetric analysis, and gel permeation chromatography. While the majority of the work presented here consists of a gold core and a poly(hexyl isocyanate) coating produced by a titanium(IV) catalyst, the general utility of the technique has been demonstrated and a wide range of structures can be prepared with small modifications in procedure. ^