Xl. Luo et al., EXPLORATION OF THE DIFFERENCE OF REACTION-RATES FOR POLYESTER AND POLYETHER URETHANE PREPOLYMERS WITH 3,3'-DICHLORO-4,4'-DIAMINODIPHENYLMETHANE, Journal of applied polymer science, 57(4), 1995, pp. 467-472
Polyester (PEPA) and polyether (PTMO) prepolymers with NCO end groups
were synthesized. The chain extension reaction of these prepolymers wi
th MOCA diamine was studied by FTIR spectrometry and found to be a sec
ond-order reaction. Data on chain extension reaction rate constants an
d activation energy showed that the chain extension reaction rate of t
he PEPA prepolymer with MOCA. was faster than that of PTMO prepolymer
with MOCA. Such a difference of chain extension reaction rate for PEPA
and PTMO prepolymers with MOCA can be explained by hydrogen bonding i
nteraction and miscibility between hard and soft segments in the cast
polyurethane elastomer. The hydrogen bonding interactions of MOCA with
PEPA prepolymer and PTMO prepolymer without chain extension reaction
convincingly demonstrated the difference of chain extension reaction i
n the polyurethane-urea systems. (C) 1995 John Wiley and Sons, Inc.