双金属氰化物催化二氧化碳与环氧丙烷聚合

研究了双金属氰化配合物(DMC)催化剂催化二氧化碳(CO2)与环氧丙烷(PO)的共聚及PO的均聚反应,考察了DMC催化剂的诱导现象。结果表明,共聚时DMC催化的诱导期比均聚短,尤其是在低CO2压力(1.0MPa)下更明显,诱导期由均聚时的45min缩短为共聚时的15min。共聚时诱导期随CO2压力升高而增加,当反应压力由1.0MPa升高至7.0MPa时,诱导期由15min增至40min。PO与CO2共聚时的引发现象不同于PO均聚:共聚引发时温度和压力突然异常升高并迅速降低至引发前的状态,而均聚引发时温度突然升高后逐渐下降。由此可知CO2能促进DMC催化剂的活化。

Copolymerization of CO2 and Propylene Oxide Catalyzed by Double Metal Cyanide Complex

The copolymerization of propylene oxide(PO) with CO2 and homopolymerization of PO catalyzed by double metal cyanide(DMC) catalyst were investigated with focus on the reaction induced period. The results showed that the copolymerization initiated by DMC catalysts has shorter induced period than that of PO homopolymerization. At low pressure(1.0 MPa) of CO2, the induction period of homopolymerization was shorten from 45 min to 15 min. The initiation time prolongs with the increase of, the induction period, and increases from 15 min for copolymerization to 40 min for homopolymerization with enhancing the CO2 pressure from 1.0 to 7.0 MPa, respectively. The induction phenomenon of copolymerization differs dramatically from that of homopolymerization. For the former case, the pressure and temperature experience a sudden abnormal increase and then rapidly return to the state before induction. While in homopolymerization process, the temperature will slowly dropped after a sudden increase occurred in the induction period. Those observations suggest that CO2 can promote the activation of the DMC catalysts.