In:
Journal of Applied Crystallography, International Union of Crystallography (IUCr), Vol. 31, No. 6 ( 1998-12-01), p. 881-889
Abstract:
A new instrument for simultaneous small-angle X-ray scattering and rheology experiments on soft solids is described. This device is based on a commercial rheometer with a shear sandwich geometry in which the sample is subjected to a planar oscillatory deformation. This instrument has been used for time-resolved small-angle X-ray scattering/rheology experiments at the Synchrotron Radiation Source, Daresbury Laboratory, England. The focus has been in particular on the effect of large-amplitude shearing on the orientation of cubic phases in gels of block copolymers formed in concentrated solutions, and on the bicontinuous cubic phase of a block copolymer melt. Representative results are presented for face-centred cubic (f.c.c.) and body-centred cubic (b.c.c.) phases in gels of poly(oxyethylene)–poly(oxybutylene) diblock copolymers, and for the bicontinuous cubic `gyroid' structure in a poly-(ethylene- alt -propylene)–poly(dimethylsiloxane) di-block copolymer melt. The orientations of the micellar b.c.c. phases in the gels and the gyroid structure (belonging to the b.c.c. space group Ia\bar 3d) following large-amplitude shearing are shown to be the same, i.e. directionally oriented crystals are produced in both cases, in which (111) directions are oriented along the shear direction.
Type of Medium:
Online Resource
ISSN:
0021-8898
DOI:
10.1107/S0021889898007699
Language:
Unknown
Publisher:
International Union of Crystallography (IUCr)
Publication Date:
1998
detail.hit.zdb_id:
2020879-0
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