| Abstract
| - The phase behavior of an oxyethylene/oxybutylene diblock copolymer (E22B7) in aqueous solution was definedusing three properties: yield stress (by rheometry and tube inversion), dynamic modulus (by rheometry), andstructure (by small-angle X-ray scattering). The boundary of immobile, structured gel (hard gel) was detectedby all three methods, giving satisfactory agreement. A structural transition within the hard gel, from bcc tohex, was detected by rheometry and SAXS. Two types of soft gel were detected and assigned to disorderedphases containing either spherical or cylindrical micelles. Comparison with results for other diblock EmBncopolymers showed a regularity of behavior influenced largely by oxyethylene-block length, with oxybutylene-block length having a minor but significant role.
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