New layered mixed divalent metal vinylphosphonates Cu^II_1−xZn^II_x(O₃PC₂H₃)⋅H₂O have been prepared from a range of pre-formed copper–zinc oxides Cu^II_1−xZn^II_xO obtained by isomorphous substitution of zinc into the tenorite-type structure of Cu^IIO. The corresponding mixed divalent copper–zinc vinylphosphonates have been characterised by powder X-ray diffraction, elemental analysis, infrared spectroscopy and thermogravimetric analysis. All compounds have been shown to consist of a single-phase solid solution that crystallises in an monoclinic unit cell, space group P2₁/c with a=9.86–9.90, b=7.61–7.64, c=7.32–7.35 Å and β=95.9–96°, with the exception of the pure zinc vinylphosphonate (x=1), the structure of which is comparable to other Zn^II(O₃PR)⋅H₂O materials. Studies of the intercalation of n-butylamine into the range of copper–zinc vinylphosphonates have demonstrated that significant modulation of the adsorption properties occurs; whereas one mole of amine is intercalated into the pure zinc vinylphosphonate to give Zn^II(O₃PC₂H₃)⋅(C₄H₉NH₂), for all other members of the series two moles of amine are coordinated to give intercalated compounds of composition Cu^II_1−xZn^II_x(O₃PC₂H₃)⋅[(C₄H₉NH₂)_1−x(C₄H₉NH₂)_x]₂ from which the amine can be sequentially removed from the different metal sites; this opens up possibilities for further applications of these materials.