Arco Chemical Technology, L.p.

Bruce H Isaacs

Leah J Langsdorf

John E Hayes

Nigel Barksby

Stephen D Seneker

Gary L Allen

Fred J Armellini

A process for activating double metal cyanide catalysts is disclosed. A polyol starter or starter/catalyst mixture is heated under vacuum under conditions effective to achieve improved stripping compared with that which can be achieved through conventional vacuum stripping. Coupling vacuum stripping with inert gas sparging or stripping in the presence of an organic solvent gives a starter/catalyst mixture that activates rapidly in an epoxide polymerization process. Rapid activation makes process start-ups reliable and reduces cycle time. The process gives polyols with lower viscosity, lower polydispersity, and lower unsaturation for better polyurethanes.

Process for rapid activation of double metal cyanide catalysts

Polyurethane elastomers exhibiting improved green strength while maintaining short demold times are prepared from ultra-low unsaturation polyoxypropylene polyols containing up to 20 weight percent internal random oxyethylene moieties. The elastomers adsorb less than 10 weight percent water at 0.degree. C. The internal polyoxyethylene moiety-containing polyoxypropylene polyols may be used to prepare ultra-low unsaturation polyoxyethylene capped polyols which are haze-free and which may be used to prepare haze-free 4,4'-MDI prepolymers. Multidisperse blends of monodisperse internal oxyethylene moiety-containing polyoxypropylene polyols of ultra-low unsaturation provide yet further improvements in elastomer processing.

Polyurethane elastomers exhibiting improved demold, green strength, and

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Media, PA, United States of America

Bruce H Isaacs