ASSOCIATION OF TRIBLOCK COPOLYMERS OF ETHYLENE-OXIDE AND BUTYLENE OXIDE IN AQUEOUS-SOLUTION - A STUDY OF B(N)E(M)B(N) COPOLYMERS

Three oxyethylene/oxybutylene triblock copolymers of similar E-block l ength but different B-block lengths (B(4)E(40)B(4), B(5)E(39)B(5), and B(7)E(40)B(7)) were prepared by sequential anionic polymerization and characterized by gel permeation chromatography and NMR spectroscopy. Their association in aqueous solution was investigated by static and d ynamic light scattering, and evidence was found for small molecular as sociates, micelles, and micelle clusters (bridged micelles). Values of the critical micelle concentrations and micellar association numbers were determined and compared with those for related diblock (E(m)B(n)) and triblock (E(m)B(n)E(m)) copolymers.