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Pulsed field gradient (PFG) nuclear magnetic resonance (NMR) was applied to study self-diffusion in a ternary blend containing equal molar volumes of the homopolymers poly(dimethylsiloxane) (PDMS) and poly(ethylethylene) (PEE), and the nearly symmetric PDMS-PEE diblock copolymer. The blend forms a bicontinuous microemulsion (BμE) below ∼83 °C, while it is in the disordered state at higher temperatures. PFG NMR has also been applied to the individual components of the blend. In the blend, we find one diffusional process in the disordered state and two diffusional processes in the BμE state. The fast process in the BμE is due to the diffusion of the PDMS homopolymers through the BμE. This diffusion is ten times slower than that of bulk PDMS at the same temperature, indicating restricted diffusion of PDMS in the BμE. The diffusion coefficient of the slower process in the ternary blend is slightly increased compared with bulk PEE. It is tentatively assigned to PEE self-diffusion. The changes in homopolymer di...

This communication describes dynamic light scattering measurements on three low molar mass symmetric polystyrene–polybutadiene diblock copolymer melts. Above but close to the order–disorder transition, four modes contribute to the time‐dependent correlation function. In the depolarized geometry there is a very fast, broad relaxation typifying the segmental reorientational dynamics and a slower, single‐exponential mode related to chain orientation and stretching. In the polarized experiments two additional processes are seen: the heterogeneity mode related to the self‐diffusion of individual copolymer molecules and a slow mode representing the translational diffusion of large (≂100 nm) clusters. Just below the order–disorder transition (ODT), the slowest mode is shifted to very long times. The heterogeneity mode gives rise to depolarized scattering below the ODT because of the anisotropy induced by the lamellar structure. With the lowest molar mass copolymer above the ODT, it could be seen that the amplitu...

‘‘Living’’ anionic polymerization offers a readily feasible preparation of very well‐controlled homo‐ or copolymers in a wide range of molar masses and chemical structures. Such samples are vital in experimental polymer physics and the technique presented here offers self‐sufficiency with such samples. The technique of anionic polymerization performed under inert atmosphere is presented here. The components of the setup are described in detail. Purification procedures for glassware and chemicals for specific polymerizations are given. Illustrative examples and results are presented.