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- Mortensen, K., et al.
(författare)
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INVERSE MELTING TRANSITION AND EVIDENCE OF 3-DIMENSIONAL CUBATIC STRUCTURE IN A BLOCK-COPOLYMER MICELLAR SYSTEM
- 1992
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Ingår i: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 68:15, s. 2340-2343
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Tidskriftsartikel (refereegranskat)abstract
- Structural studies on aqueous solutions of PEO-PPO-PEO block copolymers show three phases as the temperature is varied. At low T, the tri-block units are dissolved Gaussian chains. As T is increased still more unimers aggregate in micelles, until a volume fraction of 0.52 is reached. The micelles then crystallize in a body-centered-cubic lattice. Upon the application of a small shear, the high-T polycrystalline phase abruptly transforms into a single crystal, characterized by only quasi-long-range order in bond length, but true long-range correlations in the bond angle.
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