Novel Thermotropic Liquid Crystalline and Redox-Active Complexes of Ionically Self-Assembled Poly(ferrocenylsilane) and Dendritic Amphiphiles

A series of novel polyelectrolyte-amphiphilie complexes were prepared by ionic self-assembly of cationic linear poly(ferrocenylsilane) (PFS) of [Fe(eta-C5H4)(2)SiMe(OCH2CH2NMe3I)](n) (PFS) with anionic dendrons of 3,4,5-tris(n-alkan-1-yloxy)benzoic acid [(3,4,5)(n)G1-COOK, n = 12, 14, 16, where n was the number of carbon atoms in the alkyl tail]. These complexes PFS-(3,4,5)nG1 (n = 12, 14, 16) were characterized with XRD, FTIR, TG, DSC, cyclic voltammetry (CV), and polarized optical microscope (POM). XRD profiles indicated the presence of the crystalline phase in the complexes resulted from the dendritic amphiphiles, which formed the end-to-end bilayer lamellar structure with the long period d = 4.84, 5.34, and 5.76 nm for n, = 12, 14, and 16, respectively. With increasing the length of amphiphile alkyl tails, the stacking order was improved. The ionic thermotropic liquid crystalline state was obtained from these PFS-(3,4,5)nG1 complexes at temperature above the melting point of the dendron crystal. CV measurements indicated that these PFS-(3,4,5)nG1 complexes exhibited a good reversible redox process. Our work provides for the first time a simply and facile approach to fabricate redox-active PFS polymers with ionic thermotropic liquid crystalline phase by the ionic self-assembly.