| 摘要 |
In the present invention there are disclosed highly active double metal cyanide (DMC) catalysts. The catalysts comprise a DMC complex, and organic complexing agent, and from about 5 to about 80 percent by weight, based on the amount of catalyst, of a polyether having a number average molecular weight less than about 500 and being free of tertiary hydroxyl groups. The invented catalysts polymerize propylene oxide at a rate in excess of about 1 kg PO/g Co/min, at catalyst concentration of 100 ppm, based on the weight of finished polyether, at a temperature of 105 degC. The catalysts, which are easy to prepare, give polyether polyols with exceptionally low unsaturation levels. |
