We investigate the development of mesophase order in compositionally asymmetric (13 wt % styrene) polystyrene−polyisoprene (SI) diblock and SIS triblock copolymers. The equilibrium ordered morphology of these polymers is a body-centered-cubic (bcc) lattice of spherical S microdomains. The ordering kinetics are measured by quenching the material from above the order−disorder transition temperature (T ODT) to a temperature where the ordered phase is stable and following the structure development by time-resolved small-angle X-ray scattering and dynamic oscillatory rheological measurements. The kinetics are significantly slower than those observed for nearly symmetric polymers of similar T ODT, resulting in a wider range of experimentally accessible quench depths. The temporal evolution of the storage modulus G‘ measured at constant frequency displays a two-step increase after a quench from above the ODT, for sufficiently low temperatures and/or high molecular weights. The long-time step corresponds to the development of a bcc lattice of spherical microdomains, while the first step results from the finite time required for large-amplitude composition fluctuations to develop fully.

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Quality sample preparation for SEM is important to observe fine details without artifacts, and good preparation requires proper fixation, dehydration, drying and coating, An alternative 5 min passage in hexamethyldisilazane (HMDS) can replace critical point crying (CPD) and gives satisfactory results on many biological samples. CPD procedure may take up to 1 h per sample to ensure adequate drying, therefore a brief rinse in HMDS followed by air drying requires less time and equipment yet provides excellent results.Various biological samples were fixed in 3% glutaraldehyde; rinsed 3 times in Millonig's phosphate buffer for 10 min each; post-fixed in 1% osmium tetroxide for 1 h; rinsed as before; fixed again in 1% tannic acid (TA) for 30 min-1 h; rinsed well and partially dehydrated to 70% ethanol; placed in 1% uranyl-acetate (UA) in the dark, overnight: rinsed with 70% ethanol until UA cleared and then dehydrated through 100% ethanol.