The self-diffusion of macromolecules in binary blends of poly(ethylene glycol)

The concentration and molecular mass dependencies of the self-diffusion coe fficients were obtained for higher molecular mass component in binary blend s of the homopolymer poly(ethylene glycol) (PEG) by a nuclear magnetic reso nance method with pulsed magnetic field gradient. The shape of the diffusio n decay and its dependence on the diffusion observation time in binary PEG blends have been investigated. The experimental results were explained by h ypothesizing the existence of cluster formation in polymer melts and polyme r blends and the possibility of molecular exchange between clusters. The en tanglement time in such systems was evaluated. Copyright (C) 1999 John Wile y & Sons, Ltd.