Process for the in-situ production of polyol blends, the in-situ produced polyol blends, and their use in the production of viscoelastic foam

摘要

This invention relates to a process for the in-situ production of a blend of a polyether monol and a polyether polyol. This process comprises introducing a monol (S_i) and a double metal cyanide (DMC) catalyst into a reaction vessel, feeding an epoxide mixture into the vessel and allowing the epoxide to react with the initial starter and continuing to polymerize by feeding epoxide until the equivalent weight of the monol reaches the desired level, then continuously adding a polyfunctional starter (S_c) to the reaction vessel while continuing to feed an epoxide mixture, completing addition of the starter, and allowing the mixture to continue to polymerize until the resultant blend of polyether monol and polyether polyol has an average equivalent weight of from about 350 to about 750, and an average functionality of from about 2 to about 4. In-situ polymerized blends of a polyether monol and a polyether polyol are also part of the present invention. The present invention also relates to a process for the production of viscoelastic foams. This process comprises reacting a polyisocyanate component with an isocyanate-reactive component, in the presence of additives, wherein the isocyanate-reactive component comprises at least 50% by weight of the in-situ polymerized blend of a polyether monol and a polyether polyol as described above.