The characterization of polymer interfaces by fluorescence decay measurements

Fluorescence decay measurements of energy transfer between donor (D) and acceptor (A) chromophores covalently attached to polymers can provide rich information about a polymer system. Here we use these techniques to study two quite different polymer phenomena. The first involves the diffusion of polymer molecules across the interfaces created during latex film formation. We are able to determine diffusion coefficients for this process. The second involves the phase separation which occurs in mixtures of homopolymers and graft copolymers. Here we are able to show that where a component of the graft is highly incompatible with the homopolymer matrix, interconnected domains of very small size can form. Under certain circumstances fluorescence decay measurements in conjunction with the recent model for “energy transfer in restricted geometrics” can be used to map out the size and shape of these domains.