SYNTHESIS OF ALPHA-HYDROXY-OMEGA-AMINO POLY(ETHYLENE OXIDE) AND ITS USE IN REACTION INJECTION-MOLDING (RIM)

Computer simulations show that oligomers with two different terminal g roups with dissimilar reactivities for isocyanates give a delayed visc osity rise in polyurethanes. This is a desired behaviour for RIM proce sses. Therefore, an alpha-hydroxy-omega-amino poly(ethylene oxide) (HA PEO) has been prepared. The synthesis was carried out by the ethoxylat ion of 2-hydroxyethyl phthalimide as a blocked amine. Hydrazinolysis a ppears to be the best way to obtain the deblocked oligomer. The produc t properties were compared with an oligomeric diamine ether (Jeffamine D2000). The gel time of HAPEO (M(n) = 500) and JAD2000 (M(n) = 2000) was the same (2 sec.). The product with HAPEO had a higher modulus, a comparable impact and tensile strength and a lower elongation at break .