Phase Behavior of Block Copolymers containing Poly(vinyl pyridine) by Coordination with Metal Chloride

We studied, via small angle X-ray scattering, rheology, and transmission electron microscopy, the change of the domain spacing (D) and the order-to-disorder transition temperature (T$_{ODT})$ with the amount of cadmium chloride (CdCl$_{2})$ for polystyrene-\textit{block}-poly(2-vinyl pyridine) copolymers (PS-P2VP) and polystyrene-\textit{block}-poly(4-vinyl pyridine) copolymers (PS-P4VP). With increasing amount of CdCl$_{2}$, both D and T$_{ODT}$ of PS-P2VP increased greatly. On the other hand, with increasing amount of CdCl$_{2}$, D of PS-P4VP decreased, whereas T$_{ODT}$ of PS-P4VP increased dramatically. These results are due to different types of the coordination between CdCl$_{2}$ and nitrogen atoms in the 2-position of pyridine ring (intra-chain coordination) in PS-P2VP, compared with nitrogen atoms in the 4-position (inter-chain coordination) in PS-P4VP. This work was supported by Creative Research Initiative Program supported by KOSEF