Determination of Functional Group Distribution within Rasta Resins Utilizing Optical Analysis

摘要

In recent reports from the laboratories at Parke-Davis, solid-supported living free radical polymerization (LFRP), initiated thermally by exposure of TEMPO-methyl resin 1 to styrenyl monomers 2, was employed to access large high loading isocyanate and silyl resins. These new resins (3) were coined "Rasta resins" and were believed to have a unique macromolecular architecture typified by long straight chain polymers bearing the desired functional groups, that emanate from the phenyl groups of a cross-linked polystyrene core. In Scheme 1, the initially proposed architecture of a generic Rasta resin can be depicted by a cartoon structure (4) in which hair-like appendages represent new polymer growth from the original cross-linked bead. Alternatively, Rasta resins can be depicted by 5 wherein the shaded inner circle represents the original cross-linked core while the outer clear circle represents new polymer growth. Our attention now centered on elucidation of the functional group distribution within Rasta resins.