Coassembly of Poly(ethylene oxide)-block-poly(methacrylic acid) and N-Dodecylpyridinium Chloride in Aqueous Solutions Leading to Ordered Micellar Assemblies within Copolymer Aggregates
Abstrakt
Formation of polyelectrolyteMINUS SIGN surfactant (PEMINUS SIGN S) complexes of poly(ethylene oxide)-block-poly(methacrylic acid) (PEO705MINUS SIGN PMAA476) and N-dodecylpyridinium chloride (DPCl) in aqueous solution was studied by static and dynamic light scattering (SLS, DLS), small-angle neutron scattering (SANS), small-angle X-ray scattering (SAXS), and cryogenic transmission electron microscopy (cryo-TEM). While it was found previously [Macromolecules 1997, 30, 3519] by microcalorimetric titration that in a similar system (PEO176MINUS SIGN PMAA186) crystallization of aliphatic tails of N-dodecylpyridinium bromide did not occur, in our system it was evidenced by SAXS that upon addition of DPCl to fully ionized PEO705MINUS SIGN PMAA476 the ordered arrangement of the surfactant occurs in a certain range of PEO705MINUS SIGN PMAA476 concentrations and surfactant-to-polyelectrolyte charge molar ratio.