Complexing P2VP and P2VP-b-PEO with Wedge-Shaped Amphiphiles

We report on the structure of a system of wedge-shaped molecules with a sulfonic end group incorporated into the both the homopolymer P2VP and the block copolymer P2VP-b-PEO, at degrees of complexing of 25%, 50%, and 100%. From X-ray scattering in the bulk all three homopolymer complexes reveal a lamellar phase, which is, however, for 100% mixed with a hexagonal phase. In agreement with earlier work on thin films, the corresponding block copolymers show all a structure of PEO cylinders perpendicular to lamellae of the ligands. Between 25% and 50% neutralization the packing changes from relatively loose layers consisting of several backbone chains with ligands for 25% to a situation of single backbones with highly stretched ligands for higher degrees of neutralization. In the latter cases crystallization of the confined PEO blocks is strongly reduced.