Kinetic Isolation of Macroradicals

Kinetics of irreversible reactions between polymer chains bearing reactive groups1-4 are interesting for many reasons. Every reaction event between a pair of functional groups relies on the motion and configurations of the host macromolecules to enable the groups to meet. Consequently, rate constants reflect not only the local chemistry of the reactive groups but also static and dynamical properties of polymer chains in the liquid state. Measurements of polymer-polymer reaction rate constants, kPP, thus probe fundamental aspects of polymer science. Interpolymeric reactions are also central to a great number of applications such as free radical polymerization (FRP).5 Many phenomena in FRP are driven by the dependence of kPP on chain length and concentration.6,7 A rather complete theoretical picture for kPP by now exists.2 Theory predicts universal scaling laws for sufficiently high degrees of polymerization, N. For example, for highly reactive functional groups