| Abstract: | Two series of semi-2-IPNs based on a polyurethane and a poly(methyl acrylate) crosslinked with divinyl benzene were prepared and investigated using dynamic mechanical analysis, sonic velocity measurements, and electron microscopy. In the one series, the level of crosslinking was varied to give ultratight networks. In the other, the composition was altered, but the amount of the crosslinking agent used was kept constant. For the first series, it was concluded that the degree of crosslinking had a significant influence on the morphology and properties by controlling the amount of enforced mixing. The dynamic mechanical data for the second series fitted the Davies modulus–composition equation, indicating that both phases are continuous. |
