| 摘要 |
The amount of high molecular weight impurity present in a polyether polyol produced by alkoxylation of an active hydrogen-containing initiator using a double metal cyanide complex catalyst may be advantageously lowered by treating the catalyst prior to use in polymerization with a silylating agent. Suitable silylating agents include trialkyl halosilanes and trialkyl alkyoxysilanes. The higher purity polyether polyols thereby produced are particularly useful in the preparation of slab and molded polyurethane foams, which tend to collapse or become excessively tight when elevated levels of high molecular tail are present in the polyether polyol. |
