申请人:THE DOW CHEMICAL COMPANY
公开号:EP0133454A1
公开(公告)日:1985-02-27
Disclosed is an improved process for the production of organic polyisocyanate based molded polymers prepared from at least one organic polyisocyanate and at least one polyol in the presence of an internal release agent wherein the improvement comprises employing as said agent a polysiloxane having at least one unit of the formula
wherein R is selected from the group consisting of lower-alkyl and aryl, R' is a divalent hydrocarbon radical, and R2 is selected from the group consisting of lower-alkoxy, aryloxy, particular hydroxyalkyleneoxy, alkoxyalkyleneoxy, amino, and hydroxyalkylamino radicals.
The molding process can be repeated in many cycles before the molds require cleaning or treatment with release agent. The ease and rapidity with which the present process can be carried out makes it particularly suited to RIM production methods.
本发明公开了一种用于生产有机多异氰酸酯基模塑聚合物的改进工艺,该聚合物 由至少一种有机多异氰酸酯和至少一种多元醇在内含脱模剂的情况下制备而成,其中改进 工艺包括采用具有至少一个式中单元的聚硅氧烷作为所述脱模剂。
其中 R 选自由低级烷基和芳基组成的组,R'为二价烃基,R2 选自由低级烷氧基、芳氧基、特定羟基烷氧基、烷氧基烷氧基、氨基和羟基烷基氨基组成的组。
在模具需要清洗或使用脱模剂处理之前,可以多次重复模塑过程。本工艺简单快捷,特别适用于 RIM 生产方法。