The invention concerns thermoplastic moulding compounds containing (A) between 5 and 95 wt % of a vinylaromatic polymer having a syndiotactic structure, and (B) between 5 and 95 wt % of a copolymer of a vinylaromatic monomer and 1,1-diphenyl ethylene or its derivatives substituted at the aromatic rings optionally with alkyl groups having up to 22 carbon atoms.
