The kinetics of dibutyltin dilaurate(DBTDL) catalyzed fast urethane polymerization of polyoxypropylenepolyoxyethlene triol with uretonimine modified 4, 4’-diphenylmethane diisocyanate (l-MDI) in RIM was studied by in...The kinetics of dibutyltin dilaurate(DBTDL) catalyzed fast urethane polymerization of polyoxypropylenepolyoxyethlene triol with uretonimine modified 4, 4’-diphenylmethane diisocyanate (l-MDI) in RIM was studied by infrared spectroscopy and adiabatic temperature rise. For isothermal reaction, the overall reaction order was found to change from 3/2 to 2 with increasing reaction temperature. For adiabatic reaction, the overall reaction order was found to change from 3/2 to 2 with increasing catalyst concentration and hard segment content. The phase separation occured during the RIM urethane polymerization leads to a deviation of the kinetics relationships for higher conversion from those for lower.展开更多
文摘The kinetics of dibutyltin dilaurate(DBTDL) catalyzed fast urethane polymerization of polyoxypropylenepolyoxyethlene triol with uretonimine modified 4, 4’-diphenylmethane diisocyanate (l-MDI) in RIM was studied by infrared spectroscopy and adiabatic temperature rise. For isothermal reaction, the overall reaction order was found to change from 3/2 to 2 with increasing reaction temperature. For adiabatic reaction, the overall reaction order was found to change from 3/2 to 2 with increasing catalyst concentration and hard segment content. The phase separation occured during the RIM urethane polymerization leads to a deviation of the kinetics relationships for higher conversion from those for lower.