Interpenetrating polymer networks and polymer blends with anomalous behaviour of the viscoelastic functions

This study examined thermo–crosslinked hydrophilisated unsaturated polyester resin (HUPR), urea–formaldehyde resin (UFR), melamine formaldehyde resin (MFR) and HUPR/UFR = 90/10, 70/30, 40/60% and HUPR/MFR = 90/10, 70/30% systems. By tracing the relaxation transitions from the glassy state (GS) to a highly–elastic state (HES) the modulus G′, G″, J′, J″ and the loss factor tgδ have been investigated for these polymers. By means of temperature dependencies of lgG′, lgG″, lgJ′, lgJ″, lg(tgδ) G′, J′, and the dependencies lgG″(lgG′), lgJ″ (lgJ′) an anomalous behaviour has been observed for the dynamical mechanical (visco–elastic) functions. An amorphous polymer structure have been established with many physical components. Under a weight–ratio of 90/10% polymer blends were obtained and under other weight–ratios interpenetrating networks (IPN) were found.