A series of semi-interpenetrating polymer networks (semi-IPNs) based on acrylonitrile and poly(metal acrylates) of chromium, zinc, and copper were prepared. They are formed by cross-linking the acrylonitrile (monomer II) with divinylbenzene in the presence of linear poly(metal acrylate) (Polymer I). Investigations were carried out by swelling measurements, LR spectroscopy, differential scanning calorimetry, thermal analysis, and scanning electron microscopy. It was concluded that the swelling and, therefore, M(c) follow the order Zn-TPN > Cr-IPN > Cu-TPN. The thermal stability of the various IPNs at 200, 300, and 400 degrees C have the following order : Cu-IPN > Cr-IPN > Zn-IPN. The T-g values have also been determined for the IPN samples.