Process for making polyether alcohols having oxyethylene units by polymerization of ethylene carbonate in the presence of double metal cyanide catalysts

Patent metadata

Field	Value
Publication number	US-9758619-B2
Application number	US-201214234577-A
Country	US
Kind code	B2
Filing date	Aug 15, 2012
Priority date	Aug 25, 2011
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

Ethylene carbonate is polymerized by itself or together with another cyclic monomer such as 1,2-propylene oxide in the presence of a double metal cyanide catalyst. Most of the ethylene carbonate adds to the chain to form a terminal carbonate group, which decarboxylates to produce a hydroxyethyl group at the end of the polymer chain. The polymerization of more ethylene carbonate onto the chain end results in the formation of poly(ethyleneoxy) units. Therefore, the process provides a method for making poly(ethyleneoxy) polymers without the need to polymerize ethylene oxide. The process is useful for making polyethers that are useful as water-absorbable polymers, surfactants and as raw materials for polyurethanes. The process is also useful for increasing the primary hydroxyl content of a polyether.

First claim

What is claimed is:

1. A process for preparing a polyether containing ether-linked ethyleneoxy units, comprising copolymerizing a mixture of 5-35 weight-% ethylene carbonate and 65-95 weight-% 1,2-propylene oxide, based on the combined weight of the ethylene carbonate and 1,2-propylene oxide, wherein the ethylene carbonate is dissolved in the 1,2-propylene oxide prior to being polymerized, in the presence of an initiator compound having one or more oxyalkylatable groups and a double metal cyanide catalyst and in the substantial absence of ethylene oxide, wherein 80 to 98% of the ethyleneoxy units are ether-linked.

2. The process of claim 1 wherein the oxyalkylatable groups are hydroxyl, primary amino or secondary amino groups, or a mixture of any two or more of such groups.

3. The process of claim 2 wherein the oxyalkylatable groups are hydroxyl groups.

4. The process of claim 3 wherein the initiator contains from 2 to 8 hydroxyl groups per molecule and has a hydroxyl equivalent weight of from 70 to 2500.

5. The process of claim 3 wherein the initiator is a polyether that has a hydroxyl equivalent weight of from 500 to 2000.

6. The process of claim 1 wherein carbon dioxide is removed at least once during the polymerization.

7. The process of claim 1 , wherein the product contains carbonate groups.

8. The process of claim 1 , wherein the product contains terminal poly(ethyleneoxy) groups.

9. The process of claim 8 , which contains terminal primary hydroxyl groups.

10. The process of claim 1 , further comprising continuing the polymerization in the presence of ethylene carbonate alone or together with up to 25% by weight of 1,2-propylene oxide to introduce terminal poly(ethyleneoxy) groups and increase the primary hydroxyl content of the polyether.

Assignees

• Quintanilla Esther E
• Van Der Wal Hanno R
• Floyd Daniel C
• Linke Myriam
• Casati Francois M
• Villa Carlos M
• Masy Jean-Paul
• Borella Ricco B
• Cookson Paul
• Dow Global Technologies Llc

Inventors

• Quintanilla Esther E
• Van Der Wal Hanno R
• Floyd Daniel C
• Linke Myriam
• Casati Francois M
• Villa Carlos M
• Masy Jean-Paul
• Borella Ricco B
• Cookson Paul

Classifications

• C08G65/34 Primary

  from hydroxy compounds or their metallic derivatives {(C08G65/26 takes precedence)} · CPC title

• C08G65/2663

  Metal cyanide catalysts, i.e. DMC's · CPC title

• C08G65/00 Primary

  Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule · CPC title