Process for preparing capped polyoxyalkylene block polyethers

Claim 2

A process for the preparation of capped polyoxyalkylene block polyethers, comprising: (a) sequentially oxyalkylating an initiator molecule having one or more active hydrogens (i) with ethylene oxide in the presence of a basic cesium-containing catalyst; and (ii) one or more higher alkylene oxides in the presence of a basic oxyalkylation catalyst; and (b) capping the product of step (a) to form an alkyl, cycloalkyl, or aralkyl ether terminated polyoxyalkylene block poly­ether.

Claim 3

The process of claim 1 wherein said higher alkylene oxide is selected from the group consisting of propylene oxide and butylene oxide.

Claim 4

A process of claims 1 or 2 for the preparation of a capped polyoxyalkylene block polyether comprising (a) sequentially oxyalkylating an initiator having the formula R- -ORʹ- OH wherein R is alkyl, cycloalkyl, alkyl or aralkyl, Rʹ is ethylene, propylene, isopropylene, or butylene, and n is a natural number from 0 to about 30, with two or more alkylene oxides at least one of which is ethylene oxide, wherein said oxyalkylation with ethylene oxide take place in the presence of a basic cesium-containing catalyst, and (b) capping the resulting monohydroxyl functional polyoxyalkylene block polyether to form an alkyl, cycloalkyl, or aralkyl ether terminated polyoxyalkylene block polyether.

Claim 5

The process of claims 1 to 3 wherein said basic cesium-containing catalyst comprises cesium hydroxide.

Claim 6

The process of claims 1 to 4 wherein said baisc cesium-containing catalyst is utilized for both oxyalkyla­tion with ethylene oxide and oxyalkylation with one or more higher alkylene oxides.

Claim 7

The process of claims 1 to 3 wherein said basic catalyst is potassium hydroxide.

Claim 8

The process of claims 1 to 3 wherein said basic catalyst is a mixture comprising potassium hydroxide and cesium hydroxide.

Claim 9

The process of claims 1 to 3 wherein said cappping is accomplished by reacting a metalized polyether with a capping reagent selected from the group consisting of alkyl, cycloalkyl, and aralkyl halides.

Claim 10

The process of claim 3 wherein said initiator is selected from the group consisting of methanol, ethanol, propanol, butanol, 2-ethylhexanol, methyl carbitol, ethyl carbitol, octylphenol, nonylphenol, and C₈-C₁₈ alcohols.

Claim 11

The process of claim 3 wherein a catalyst comprising cesium hydroxide is utilized for all oxyalkyla­tions.

Claim 12

The process of claims 1 to 3 and 9 wherein said basic cesium-containing catalyst is selected from the group consisting of cesium oxide, cesium acetate, cesium carbo­nate, and the cesium alkoxides of C₁-C₈ lower alkanols.

Claim 13

The process of claim 8 wherein said metallized polyether is prepared by reacting the polyether prepared in steps (a)(i) and (ii) with a metalizing reagent selected from the group consisting of the hydrides and alkoxides of the alkali metals, alkaline earth metals, and aluminum metal.