A series of segment polyurethane-ureas from different kind of aromahc diamine chain extenders were prepared by laboratory-scale RIM machine. IR

DSC

DMTA

SEM have been used in comparing with tensile testing results to study the stmcture and properties of PUU. The influences of hard segments consisting of disocyanate and one of the three extenders (MDA

DETDA and CAMDA) on structure and properties of RIM PUU elastomers showed that the interface force index of soft-hard segment domain for the MDA-based material was smaller and its degree of phase separation was greater than that based on either DETDA or CAMDA

while the DETDA-based one had ideal inter-face force index and adequate degree of phase separation resulting in its best properties among the three. Moreover

the RIM material based on DETDA had less dependence of modulus on temperature compared with materials based on either MDA or CAMDA.