Selective Molecular−Complex Phase Formation of Syndiotactic Polystyrene with a Styrene Dimer

The possible formation of molecular−complex phases of s-PS with styrene dimers has been investigated by their sorption in amorphous and nanoporous δ-form films. X-ray diffraction, 13 C solid state NMR, and FTIR analyses have shown that only 1,3-diphenylbutane (dpb), but not 1,4-diphenylbutane, forms a highly stable molecular−complex with s-PS. Preliminary structural considerations indicate that this s-PS/dpb molecular−complex phase presents an intercalate structure, with host-monomer-unit/guest stoichiometric ratio of 4/1 and with a guest conformation with anti C2−C3 bond. Guest conformational behavior has allowed to discriminate, for the first time by a NMR technique, between guest molecules located in crystalline and amorphous s-PS phases. Presently dpb is the s-PS guest with maximum volume (≈0.36 nm 3 ) and maximum number of non-hydrogen atoms ( n = 16).