Uniform, High-Aspect-Ratio, And Patchy 2d Platelets By Living Crystallization-Driven Self-Assembly Of Crystallizable Poly(Ferrocenyldimethylsilane)-Based Homopolymers With Hydrophilic Charged Termini

Two-dimensional (2D) seeded growth of poly-(ferrocenyldimethylsilane) (PFS) homopolymers that possess hydrophilic charged termini in solution has been investigated using the living crystallization-driven self-assembly method. The charge-terminated homopolymers, PFSn[NMe3]I, were synthesized through a combination of living anionic polymerization and post-polymerization thiol-ene "click" chemistry. Uniform and patchy high-aspect-ratio 2D structures were obtained by seeded growth in solution. We show that the aspect ratio of the resultant 2D platelets could be controlled over a wide range (ca. 2-20) by changing either the solvent polarity of the medium in which seeded growth was conducted, the substituents on the charged terminal group, or the characteristics of the seed micelle. The counteranion associated with the charge-terminated PFS[NMe3](+) homopolymers was found to have a substantial effect on the resulting morphology and colloidal stability of the resulting 2D platelets, which may be a consequence of relatively high charge density of the terminal quaternary ammonium cation.