MICELLIZATION OF DIBLOCK COPOLY(OXYETHYLENE OXYBUTYLENE) IN AQUEOUS-SOLUTION

Six diblock copoly(oxybutylene/oxyethylene)s (E92B7, E50B13, E49B8, E5 0B4, E24B10 and E27B5, where E represents oxyethylene and B represents oxybutylene) have been prepared by sequential anionic copolymerisatio n and their micellisation in aqueous solution investigated. Surface te nsion, static and dynamic light scattering and gel permeation chromato graphy techniques were used to study solutions at temperatures in the range 20 to 50-degrees-C over a wide concentration range from dilute t o 100 g dm-3. The micellar properties reported are critical micelle co ncentrations, micellar molar masses and radii. The thermodynamics of m icellisation of E(m)B(n) diblock copolymers is discussed in relation t o that of related triblock copolymers (E(m)B(n)E(m) and E(m)P(n)E(m), where P represents oxypropylene).