Filled interpenetrating networks: their formation and viscoelastic properties

The kinetics of curing, the microphase separation process (MPS) and the viscoelastic properties of interpenetrating polymer networks (IPNs) based on crosslinked polyurethane and linear poly(butyl methacrylate) were studied in the presence of two fillers—talc and polymeric fine‐disperse triethylene glycol dimethacrylate. It was found that introducing filler into the reaction mixture changes the reaction kinetics and degree of microphase separation, which in turn affects the viscoelastic properties of the IPNs. The data obtained by dynamic mechanical spectroscopy and differential scanning calorimetry for filled semi‐IPNs and calculations of the degree of segregation of the components show that filler introduction results in MPS inhibition on account of a local increase in viscosity near the solid interface, i.e. compatibility is increased.