Direct non-radiative energy transfer across a sharp polymer interface

Abstract

A simple interfacial model system is chosen in which fluorescent donors and acceptors attached to incompatible polymer chains are randomly distributed in respective phases separated by a sharp interface. Direct non-radiative energy transfer (DET) across the interface between the labeled polymer phases is observed by fluorescence decay measurements. The quantum efficiency of energy transfer ( Φ ET) is used to quantify DET. We show that Φ ET increases as the interfacial contact area between the phases increases and is inversely proportional to the diameter of the dispersed spherical donor-labeled particles. The data indicate that the degree of interpenetration at the interface is less than 2 nm.