INVERSE MELTING TRANSITION AND EVIDENCE OF 3-DIMENSIONAL CUBATIC STRUCTURE IN A BLOCK-COPOLYMER MICELLAR SYSTEM
Artikel i vetenskaplig tidskrift, 1992

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.

neutron-scattering

behavior

aqueous-solution

Författare

K. Mortensen

W. Brown

Bengt Nordén

Institutionen för fysikalisk kemi

Physical Review Letters

0031-9007 (ISSN) 1079-7114 (eISSN)

Vol. 68 2340-2343

Ämneskategorier

Fysik

DOI

10.1103/PhysRevLett.68.2340