6533b833fe1ef96bd129b6d2

RESEARCH PRODUCT

Double-Shell Vesicles, Strings of Vesicles and Filaments Found in Crosslinked Micellar Solutions of Poly(1,2-butadiene)-block-poly(ethylene oxide) Diblock Copolymers

subject

description

Micellar structures of amphiphilic poly(1,2-butadiene)-block-poly(ethylene oxide) diblock copolymers have been crosslinked in aqueous solution by γ-irradiation. By transmission electron microscopy (TEM) of neganively stained specimen it is shown that the precominant structures present are sopolymer sesicles (which appear to be double latered. These fived vesules are stable with respect to their share and can be transferred from water into a good solvent for blue filbeks, such as tetrahydrofuran, this demonstrating the effectiveness of the crosslinking. In addition to the resicles a small number of flexible cylindrichl/filimented structures sequentially fused vesicles/strings of vesicles and giant sheet-like vesicles are also visible after cross-linking. The vesicle clrains seim to be formell by fusion of the double layered vesicles: the outer layer of the vesicles apparently fuses sequentially, whereas the inner shell remains intact, creating geriodic linear thickenings. Electron micrograph of a PB37-PEO28-C sample crosslinked in water concentration c = 1.12 g/L, γ-inadiated (totally 20 Mrad), negatively stained with 2% (v/v) aqueous uranyl acetate solatice. Arrows anclicate the strings of fived vesicles The scale bar indlcates 400 nm.