title: Fluctuation dynamics of block copolymer vesicles.
abstract: X-ray photon correlation spectroscopy was used to characterize the wave-vector- and temperature-dependent dynamics of spontaneous thermal fluctuations in a vesicle (L4) phase that occurs in a blend of a symmetric poly(styrene-ethylene/butylene-styrene) triblock copolymer with a polystyrene homopolymer. Measurements of the intermediate scattering function reveal stretched-exponential behavior versus time, with a stretching exponent slightly larger than 2/3. The corresponding relaxation rates show an approximate q(3) dependence versus wave vector. Overall, the experimental measurements are well described by theories that treat the dynamics of independent membrane plaquettes.
authors.affiliation: Department of Physics, Yale University, New Haven, CT 06511, USA.
authors.forename: P
authors.initials: P
authors.lastname: Falus
authors.forename: M A
authors.initials: MA
authors.lastname: Borthwick
authors.forename: S G J
authors.initials: SG
authors.lastname: Mochrie
mesh_terms: D003198:Computer Simulation; D007700:Kinetics; D008081:Liposomes / Q000737:chemistry*; D046911:Macromolecular Substances / Q000032:analysis / Q000737:chemistry; D008560:Membrane Fluidity; D008958:Models, Molecular; D008968:Molecular Conformation; D009038:Motion; D011108:Polymers / Q000032:analysis / Q000737:chemistry; D011137:Polystyrenes / Q000032:analysis / Q000737:chemistry*; D013052:Spectrometry, X-Ray Emission / Q000379:methods*
chemical_list: D008081:Liposomes; D046911:Macromolecular Substances; D011108:Polymers; D011137:Polystyrenes