Swelling behavior and thermal stability of poly(methylmethacrylate) crosslinked by the oxozirconium cluster Zr4O2(methacrylate)12

A new isomer of the oxozirconium cluster Zr4O2(methacrylate)(12) was obtained by reaction of zirconium butoxide with an excess of methacrylic acid, Contrary to the known isomer, the structure is centrosymmetric with a planar, rhombic Zr-4 core, Copolymerization with a 56-207-fold excess of methlylmethacrylate results in cluster-crosslinked poly(methylmethacrylate) that swells in ethyl acetate but does not dissolve. The solvent uptake during smelling decreases and the thermal stability improves with an increasing portion of the cluster. Copyright (C) 2001 John Wiley R:Sons, Ltd.