Thermoreversible gelation of syndiotactic polystyrene: Effect of solvent type

The temperature-concentration phase diagrams of syndiotactic polystyrene (sPS)/benzene gels and sPS/toluene gels establish the existence of two polymer-solvent compounds in both systems. In particular it is found that the stoichiometries of the compounds differ with the type of solvent : the stoichiometries, expressed as solvent molecules/monomer are respectively for the benzene 4/1 and 1/1 and for the toluene 0.8/1 and 1/4. Neutron diffraction patterns allow us to confirm the existence of differents compounds in sPS/toluene gel and sPS/benzene gel.