In-situ formed polyether polyols, a process for their preparation, and a process for the preparation of polyurethane foams

Patent metadata

Field	Value
Publication number	US-11718705-B2
Application number	US-202117386844-A
Country	US
Kind code	B2
Filing date	Jul 28, 2021
Priority date	Jul 28, 2021
Publication date	Aug 8, 2023
Grant date	Aug 8, 2023

Abstract

This invention relates to an in-situ formed polyether polyol blend having an overall functionality of 2 to 3 and an overall hydroxyl number of 40 to 220 mg KOH/g. A process for preparing these in-situ formed polyether polyol blends is also disclosed. These in-situ formed polyether polyol blends are suitable for a process of preparing viscoelastic flexible polyurethane foams.

First claim

What is claimed is:

1. An in-situ formed polyether polyol blend having an overall functionality of 2 to 3, an overall hydroxyl number of 40 to 220 mg KOH/g, and comprising:
(a) a monol initiated oxyalkylene ether having a hydroxyl number of less than or equal to 56 mg KOH/g polyol, and containing less than or equal to 20% of copolymerized oxyethylene, based on the total weight of monol initiated oxyalkylene ether (a);
(b) a polyether polyol having a functionality of 2 to 8, a hydroxyl number of 20 to 240 mg KOH/g and containing at least 50% of copolymerized oxyethylene, based on the total weight of component (b);
(c) a polyether polyol having a hydroxyl number of 80 mg KOH/g polyol to 220 mg KOH/g polyol, a nominal functionality of 2, and containing 5 to 45% of copolymerized oxyethylene, based on the total weight of polyether polyol (c);
and
(d) a polyether polyol having a hydroxyl number of 80 mg KOH/g polyol to 220 mg KOH/g polyol, a nominal functionality of greater than 2 to 8, and containing 5 to 45% of copolymerized oxyethylene, based on the total weight of polyether polyol (d);
wherein (a) said in-situ formed polyether polyol blend comprises from 15 to 40% by weight of said monol initiated oxyalkylene ether (a), from 3 to 45% by weight of said polyether polyol (b), from 8 to 30% by weight of said polyether polyol (c), and from 20 to 60% by weight of said polyether polyol (d), with the sum of the %'s by weight of (a), (b), (c) and (d) totaling 100% by weight of said in-situ formed polyether polyol blend.

2. The in-situ formed polyether polyol blend of claim 1 , wherein said in-situ formed polyether polyol blend is phase stable.

3. The phase stable in-situ formed polyether polyol blend of claim 2 , which comprises from 15 to 40% by weight of (a) the monol initiated oxyalkylene ether; from 3 to 10% by weight of (b) the polyether polyol; from 15 to 30% by weight of (c) the polyether polyol; and from 20 to 60% by weight of (d) the polyether polyol, with the sum of the %'s by weight of (a), (b), (c) and (d) totaling 100% by weight of the phase stable in-situ formed polyether polyol blend.

4. The in-situ formed polyether polyol blend of claim 1 , wherein the monol initiated oxyalkylene ether (a) is prepared with a starter comprising a polyoxypropylene monol having a hydroxyl number of 80 mg KOH/g or less.

5. The in-situ formed polyether polyol blend of claim 1 , wherein (a) the monol initiated oxyalkylene ether comprises an oxypropylene block next to a low equivalent weight starter residue, followed by a mixed oxypropylene and oxyethylene terminal block.

6. The in-situ formed polyether polyol blend of claim 1 , wherein (b) the polyether polyol comprises a 100% oxyethylene block next to a low equivalent weight starter residue, followed by a mixed block of oxypropylene and oxyethylene.

7. The in-situ formed polyether polyol blend of claim 1 , wherein (c) the polyether polyol comprises a first mixed oxypropylene and oxyethylene block followed by a second mixed oxypropylene and oxyethylene block that has a higher copolymerized oxyethylene content compared to the copolymerized oxyethylene content of the first mixed oxypropylene and oxyethylene block.

8. The in-situ formed polyether polyol blend of claim 7 , wherein the second mixed oxypropylene and oxyethylene block of polyether polyol (c) has a copolymerized oxyethylene content that is at least 10 weight % higher than the oxyethylene content of the first mixed oxypropylene and oxyethylene block of polyether polyol (c).

9. The in-situ formed polyether polyol blend of claim 1 , wherein (d) the polyether polyol comprises a first mixed oxypropylene and oxyethylene block followed by a second mixed oxypropylene and oxyethylene block that has a higher copolymerized oxyethylene content compared to the copolymerized oxyethylene content of the first mixed oxypropylene and oxyethylene block.

10. The in-situ formed polyether polyol blend of claim 9 , wherein the second mixed oxypropylene and oxyethylene block of polyether polyol (d) has a copolymerized oxyethylene content that is at least 10 weight % higher than the oxyethylene content of the first mixed oxypropylene and oxyethylene block of polyether polyol (d).

11. A process of preparing the in-situ formed polyether polyol blend of claim 1 , comprising:
I) introducing into a reaction vessel a mixture comprising:
(1) an initially charged starter (S i ) comprising a monofunctional compound having a hydroxyl number of less than or equal to 80 mg KOH/g,
and
(2) a double metal cyanide catalyst;

II) feeding
(1) an epoxide comprising propylene oxide and ethylene oxide in a weight ratio of 100:0 to 80:20,
into the reaction vessel;

III) allowing the epoxide mixture and the initially charged starter (S i ) to react and to polymerize by feeding the epoxide until the equivalent weight of the monofunctional compound is increased by at least 10% by weight and reaches a value between 1,500 and 6,000;
IV) feeding
(1) an epoxide comprising propylene oxide and ethylene oxide in a weight ratio of 50:50 to 20:80,
while continuously adding
(2) a low equivalent weight continuously added starter (S c ) having a nominal functionality of 2 to 8, and an equivalent weight of 28 to 400,
into the reaction vessel;

V) completing addition of the continuously added starter (S c );
VI) allowing the mixture to continue to polymerize in the reaction vessel thereby forming
(1) an intermediate in-situ formed polyether polyol blend which has an overall hydroxyl number of 10 to 200 mg KOH/g, an overall functionality of greater than 1 to 3, and which comprises
(a) a monol initiated oxyalkylene ether having a hydroxyl number of less than or equal to 56 mg KOH/g, and containing less than or equal to 20% by weight of copolymerized oxyethylene, based on 100% by weight of (a),
and
(b) a polyether polyol having a hydroxyl number of 20 to 240 mg KOH/g, a nominal functionality of 2 to 8, and containing at least 50% by weight of copolymerized oxyethylene, based on the total weight of the polyether polyol (b);

VII) feeding
(1) an epoxide comprising propylene oxide and ethylene oxide in a weight ratio of 95:5 to 55:45,
while continuously adding
(2) a low equivalent weight continuously added starter (S c ) having a nominal functionality of 2 to 8, and an equivalent weight of 28 to 100
into the reaction vessel;

VIII) completing addition of the continuously added starter (S c ) and epoxide thereby forming in addition to monol initiated oxyalkylene ether (a) and polyether polyol (b);
(c) a polyether polyol having a hydroxyl number of 80 to 220 mg KOH/g polyol, a nominal functionality of 2, and containing 5 to 45% by weight of copolymerized oxyethylene, based on the total weight of the polyether polyol (c),
and
(d) a polyether polyol having a hydroxyl number of 80 to 220 mg KOH/g polyol, a nominal functionality of greater than 2 to 8, and containing 5 to 45% by weight of copolymerized oxyethylene, based on the total weight of polyether polyol (d).

12. The process of claim 11 , wherein the in-situ formed polyether polyol blend is phase stable.

13. The process of claim 12 , wherein the phase stable in-situ formed polyether polyol blend comprises from 15 to 40% by weight of (a) the monol initiated oxyalkylene ether; from 3 to 10% by weight of (b) the polyether polyol; from 15 to 30% by weight of (c) the polyether polyol; and from 20 to 60% by weight of (d) the polyether polyol, with the sum of the %'s by weight of (a), (b), (c) and (d) totaling 100% by weight of the phase stable in-situ formed polyether polyol blend.

14. The process of claim 11 , wherein the contin

Assignees

• Covestro Llc

Inventors

• Lewis Sharlene A
• Reese Jack R

Classifications

• C08G18/485 Primary

  containing mixed oxyethylene-oxypropylene or oxyethylene-higher oxyalkylene end groups · CPC title

• C08G18/7621

  being toluene diisocyanate including isomer mixtures · CPC title

• C08G18/7671

  containing only one alkylene bisphenyl group · CPC title

• C08G65/12

  containing organo-metallic compounds or metal hydrides · CPC title

• C08J9/125

  Water, e.g. hydrated salts · CPC title