Long‐range order in physical networks of gel‐forming triblock copolymer solutions

Structural studies on physical gels, based on a triblock copolymer and a solvent selective for its midblocks, are presented. Gel formation in such systems arises due to interconnected microdomains that form the junctions in a three‐dimensional network. Small angle X‐ray scattering studies revealed that the physical networks show either short‐range order, described by an effective hard sphere model, or long‐range order, where junctions are arranged on a cubic lattice. The emerging morphology depends on the thermal conditions during preparation of such systems, which essentially reflects a competition among microdomain ordering and formation of the physical network. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 1833–1840, 1999