Proton spin diffusion (SD) experiments performed on low-field NMR spectrometers are a valuable means for the estimation of domain sizes in phase-separated polymers. We here investigate the interplay of the SD effect and fast T1 relaxation by means of fits of data taken for two different polystyrene-polybutadiene di- and multiblock copolymers to numerical simulations. We demonstrate the necessity to explicitly include an interphase of intermediate mobility, and further show that a previously published, popular calibration of the SD coefficient for mobile polymer phases based on the transverse relaxation time T2 should be revised.
- Henriette W Meyer
- Horst Schneider
- Kay Saalwächter
