In the copolymerization of CO2 and propylene oxide

the copolymers with designed molecular weight and OHfunctionality can be obtained by addition of certain regulators. The copolymerization was found slower than that without regulators. The regulation is recognized to be the chain transfer reaction between the active hydrogen and the active centers of the catalyst. Mechnism for this copolymerization was suggested and a rate equation was accordingly deduced. The transfer constants were determined for regulators such as H2O

1

4-butanediol

1

6-hexanediol

and 1

1

1-trimethanolpropane.Yields of the copolymerization in the presence of such regulators at various reaction time were calculated according to the developed principle.The results were consistent with the experimental data.