Damping materials based on polyurethane/polyacrylate IPNs: dynamic mechanical spectroscopy, mechanical properties and multiphase morphology

Four kinds of polyurethane/polyacrylate interpenetrating polymer networks ( crosslinked polyacrylate semi-IPNs, crosslinked polyurethane semi-IPNs, all -IPNs and all-IPNs with opposite charge groups) were synthesized by a simul taneous polymerization process. Their damping properties, mechanical proper ties and multiphase morphology were investigated by automatic torsional bra id analysis, an Instron tester, small-angle X-ray scattering (SAXS) and tra nmission electron microscopy (TEM). The results show that the attraction be tween positively charged groups and negatively charged groups improved the miscibility of the two components. When the weight ratio of polyurethane/po lyacrylate was 1:2, the resulting IPN materials possessed better damping an d mechanical properties, and the specific surface area reached a maximum. ( C) 1999 Society of Chemical Industry.