Process for preparing polyoxyalkylene glycol ethers using block polymers as demulsifiers

Abstract

The invention provides a process for preparing polyoxyalkylene glycol monoethers and/or diethers by reacting an alkoxide with an alkylating agent, which comprises adding water and block polymers which are obtainable from a compound which comprises from 1 to 30 carbon atoms and from 1 to 25 hydroxyl groups, amino groups or both by its blockwise alkoxylation with at least 2 different blocks of in each case from 1 to 200 mol of C2- to C4-alkylene oxide to the mixture of alkoxide, alkylating agent and polyoxyalkylene glycol ether which has formed.

Description

EXAMPLES

Example 1: (Comparative)

Preparation of Polypropylene Glycol Allyl Butyl Ether without Breaker Addition

In a stirred reactor with temperature and pressure monitoring, 96.4 g of a polypropylene glycol allyl ether having a mean molar mass of 1400 g/mol are admixed with 6.43 g of sodium hydroxide at 80° C. with stirring under nitrogen. Subsequently, 19.28 g of butyl chloride are added dropwise within one hour. The reactor is heated to 120° C. for postreaction and stirred at this temperature for another three hours. Subsequently, excess butyl chloride is distilled off and cooled to 90° C. With stirring, exactly the amount of water required to bring the amount of sodium chloride into solution is added.

Example 2

Preparation of Polypropylene Glycol Allyl Butyl Ether with Breaker Addition

The procedure is as in Example 1, with the difference that 50 ppm of a block addition product of 40% by weight of ethylene oxide and 60% by weight of propylene oxide to propylene glycol have additionally been added to the aqueous polypropylene glycol allyl butyl ether.

Example 3 (Comparative)

Preparation of Polyalkylene Glycol Allyl Butyl Ether without Breaker Addition

In a stirred reactor with temperature and pressure monitoring, 96.5 g of a polyalkylene glycol allyl ether having a mean molar mass of 1600 g/mol and a mixing ratio of ethylene glycol to propylene glycol of 3 to 1 are admixed with 3.7 g of sodium hydroxide at 80° C. with stirring under nitrogen. Subsequently, 11.6 g of butyl chloride are slowly added dropwise. The reactor is heated to 120° C. for postreaction and stirred at this temperature for three hours. Subsequently, excess butyl chloride is distilled off and the mixture is cooled to 90° C. With stirring, exactly the amount of water required to bring the amount of sodium chloride into solution is added.

Example 4

Preparation of Polyalkylene Glycol Allyl Butyl Ether with Breaker Addition

The procedure is as in Example 3, with the difference that 50 ppm of a block addition product of 40% by weight of ethylene oxide and 60% by weight of propylene oxide to propylene glycol, which has been crosslinked with bisphenol A diglycidyl ether up to a molecular weight Mw of 10 000 g/mol (measured by GPC), have additionally been added to the aqueous polyalkylene glycol allyl butyl ether.

Example 5 (Comparative)

Preparation of Polyalkylene Glycol Allyl Methyl Ether without Breaker Addition

In a stirred reactor with temperature and pressure monitoring, 99.6 g of a polyalkylene glycol allyl ether having a mean molar mass of 2000 g/mol and a mixing ratio of ethylene glycol to propylene glycol of 1 to 1 are admixed with 0.75 g of sodium hydroxide at 80° C. with stirring under nitrogen. Subsequently, 0.95 g of methyl chloride is slowly added dropwise. The reactor is heated to 120° C. for postreaction and stirred at this temperature for a further three hours. Thereafter, excess butyl chloride is distilled off and the mixture is cooled to 90° C. With stirring, the amount of water required to bring the amount of sodium chloride into solution is added.

Example 6

Preparation of Polyalkylene Glycol Allyl Methyl Ether with Breaker Addition

The procedure is as in Example 5, with the difference that 50 ppm of a block addition product of 40% by weight of ethylene oxide and 60% by weight of propylene oxide to propylene glycol, which has been crosslinked with bisphenol A diglycidyl ether up to a molecular weight Mw of 10 000 g/mol (measured by GPC), and has subsequently been propoxylated with 30 mol of propylene oxide, have additionally been added to the aqueous polyalkylene glycol allyl methyl ether.

Results of the Phase Separation Experiments:

To determine the effectiveness of the emulsion breaker, the water separation from the crude product emulsion was determined as a function of time. To this end, in each case 100 ml of the crude product emulsion were introduced into breakage bottles (conical, screw-closeable, graduated glass vessels). Thereafter, the breakage bottles were placed into a temperature-controlled bath and the water separation was monitored at 80° C.

	TABLE 1
	Water separation [ml] per unit time
Ex.	10 min	30 min	60 min	2 h	3 h	4 h	5 h	6 h	12 h	24 h
1	0	0	0	2	4	6.5	9	11.5	16.5	complete
2	2	4	8	10	13.5	16	17.5	complete
3	0	0	0	0	1	1	2.5	4	7	12.5
4	2	2.5	9	12.5	14.5	18	complete
5	0	0	0	0	0	0	0	1	3	4.5
6	5	11	16	complete

Claims

1. A process for preparing a polyoxyalkylene glycol monoether or a diether or a mixture thereof, said process comprising reacting a mixture comprising an alkoxide and an alkylating agent, said reacting comprising adding to said mixture water and a block polymer which is obtained from a compound which comprises from 1 to 30 carbon atoms and from 1 to 25 hydroxyl groups, amino groups or both by its blockwise alkoxylation with at least 2 different blocks of in each case from 1 to 200 mol of C2- to C4-alkylene oxide.

2. The process as claimed in claim 1, in which the polyoxyalkylene glycol monoether or diether or mixture thereof corresponds to formula 2 R—O-(AO)y—R1   (2)in whichR is hydrogen, a hydrocarbon group having from 1 to 24 carbon atoms or an R*—C(O)— group where R* is a hydrocarbon group having from 1 to 24 carbon atoms,R1 is a hydrocarbon group having from 1 to 12 carbon atoms,AO is an alkoxy group, andy is from 1 to 200.

3. The process as claimed in claim 2, in which y is from 2 to 100.

4. The process of claim 2 in which R is a group selected from the group consisting of an alkyl group having from 1 to 24 carbon atoms, an alkenyl group having from 2 to 24 carbon atoms, a group of the formula R*—C(O)— where R* is a hydrocarbon group having from 1 to 24 carbon atoms, a phenyl group, a benzyl group, an allyl group and mixtures thereof.

5. The process of claim 2, in which R comprises from 4 to 12 carbon atoms.

6. The process of claim 2, in which R1 is selected from the group consisting of an alkyl having from 1 to 12 carbon atoms, an alkenyl having from 2 to 12 carbon atoms, a phenyl, a benzyl, an allyl and mixtures thereof.

7. The process of claim 2, in which R1 comprises from 2 to 8 carbon atoms.

8. The process of claim 2, in which AO comprises at least one propoxy or butoxy group.

9. The process of claim 1, in which the block polymer corresponds to the formula 3

10. The process as claimed in claim 9, in which Y is NR5, the compound of the formula (3) has at least two active hydrogen atoms, and in which q is equal to 2 or greater than 2.

11. The process as claimed in claim 9, in which R3 bears alkoxy groups of the formula -(A-O)I—(B—O)m-(A-O)n—.

12. The process of claim 9, in which q is from 2 to 20.

13. The process of claim 1, in which the block polymer is crosslinked to provide a crosslinked block polymer.

14. The process as claimed in claim 13, in which the crosslinked block polymer is used in alkoxylated form, wherein the alkoxylation is performed with from 5 to 700 g of a C2- to C4-alkylene oxide per 100 g of crosslinked block polymer.

15. The process of claim 1, wherein the mixture further comprises a codemulsifier selected from the group consisting of a) an alkoxylated alkylphenol-aldehyde resinb) an alkoxylated polyethyleneimine, and a mixture thereof.

16. The process of claim 13, wherein the crosslinked block polymer is crosslinked by the reaction of the block polymer with an compound selected from the group consisting of a bi-glycidyl ether, a tri-glycidyl ether, a tetraglycidyl ether and mixtures thereof; or by esterification with a polybasic dicarboxylic acid or an anhydride of the dicarboxylic acid, or a mixture thereof; or by reaction with a polyvalent isocyanate.

17. The process of claim 14, wherein the alkoxylation is performed with from 30 to 300 g per 100 g of the crosslinked block polymer.