Miscibility studies of some semi-interpenetrating polymer networks based on an aromatic polyurethane and epoxy resin

Glass transition temperatures of some semi-interpenetrating polymer networks based on aromatic polyurethane and cross-linked epoxy resin were determined by differential scanning calorimetry. The influence of increasing epoxy network content on the glass transition temperatures was studied. Absolute heat capacities and cross-linking densities were determined. It was observed that the glass transition temperatures increased with increasing epoxy resin content until phase separation. Miscibility studies were conducted by applying Fox and Gordon-Taylor equations. Morphological studies were conducted by optical microscopy and scanning electron microscopy.