Formation of Lenticular Platelet Micelles via the Interplay of Crystallization and Chain Stretching: Solution Self-Assembly of Poly(ferrocenyldimethylsilane)-block-poly(2-vinylpyridine) with a Crystallizable Core-Forming Metalloblock

Abstract

The influence of solvent composition on micelle morphology has been investigated for two crystalline-coil poly(ferrocenyldimethylsilane-block-2-vinylpyridine) (PFS-b-P2VP) diblock copolymers with different block ratios (5:1 and 1:1). The solution self-assembly of these materials was explored in solvent mixtures containing different ratios of a good solvent for both blocks (THF) and a selective solvent for the P2VP block (isopropanol). Various micellar morphologies such as spheres and platelets were characterized using transmission electron microscopy (TEM), selected area electron diffraction (SAED), dynamic light scattering (DLS), wide-angle X-ray scattering (WAXS), and atomic force microscopy (AFM). The results showed that the solution self-assembly of PFS-b-P2VP block copolymers (5:1, 1:1) gave spherical micelles with an amorphous PFS core at low THF content (10 vol %). Subsequently, the amorphous spheres were slowly transformed into platelet micelles with a lenticular shape that consisted of a crystall...