On the Clathrate Structures of Syndiotactic Poly(m-methylstyrene)

摘要

The crystal structures of clathrate forms of syndiotactic poly(m-methylstyrene) containing guest molecules having different steric hindrance (CS_2, benzene and orto-dichlorobenzene) are presented. The structures are all characterized by polymer chains in s(2/1)2 helical conformation and guest molecules packed in an orthorhombic unit cell according to the space group Pcaa. All the presented clathrates belongs to p class indipendently from the dimensions of the guest molecule. In this aspect they differ both from clathrate forms of syndiotactic polystyrene, all belonging to a class, and from clathrate forms of syndiotactic poly(p-methylstyrene) that belong to a or 3 class according to the steric hindrance of the guest molecule.