摘要 |
Double metal cyanide (DMC) catalysts and methods for making them are disclosed. The catalysts comprise a DMC compound, an organic complexing agent, and optionally, a functionalized polymer. The key component is the complexing agent, which comprises a C3-C5 aliphatic alcohol a cyclic, bidentate compound selected from lactams and lactones. Polyether polyols made from the catalysts contain reduced levels of high-molecular-weight (Mn greater than 400,000) components and consistently perform better in urethane applications such as flexible and molded foams. |