Hydrolysis-stable polyurethane for coating elements in maritime applications

• US 10,442,885 B2
• Filed: 12/11/2013
• Issued: 10/15/2019
• Est. Priority Date: 12/13/2012
• Status: Active Grant

• Current Assignee: BASF SE
• Original Assignee: BASF SE
• Inventors: Kamm, Andre, Liese, Julia, Gust, Karl
• Primary Examiner(s): Walters, Jr., Robert S
• Application Number:
  US14/102,687
• Publication Number:
  US 20140170352A1
• Time in Patent Office: 2,134 Days
• Field of Search: None
• CPC Class Codes: C08G 18/4812 Mixtures of polyetherdiols with polyetherpolyols having at least three hydroxy groups
• CPC Class Codes: C08G 18/4837 and other oxyalkylene units
• CPC Class Codes: C08G 18/4866 having a low unsaturation value
• CPC Class Codes: C08G 18/6674 with compounds of group C08G18/3203
• CPC Class Codes: C08G 18/724 Combination of aromatic polyisocyanates with (cyclo)aliphatic polyisocyanates
• CPC Class Codes: C08G 18/7664 containing alkylene polyphenyl groups
• CPC Class Codes: C08G 18/792 formed by oligomerisation of aliphatic and/or cycloaliphatic isocyanates or isothiocyanates
• CPC Class Codes: C09D 175/08 from polyethers
• CPC Class Codes: F16L 59/143 Pre-insulated pipes
• CPC Class Codes: Y10T 29/49826 Assembling or joining
• CPC Class Codes: Y10T 428/1393 Multilayer [continuous layer]

Abstract

A process for producing a polyurethane-coated conduit element includes mixing a) a mixture of aromatic and aliphatic polyisocyanate with, b) at least one polymeric compound having at least two hydrogen atoms which are reactive toward isocyanate, c) at least one chain extender, d) a catalyst, and e) optionally at least one other auxiliary, additive, or both, to form a reaction mixture; applying the reaction mixture to a conduit element; and allowing the reaction mixture to react to form a polyurethane layer. The polyurethane-coating conduit element is suitable for maritime applications in the oil and gas industry, which polyurethane has improved hydrolysis stability at high temperatures and nevertheless satisfies the high mechanical demands in the oil and gas industry.

Claims

1. A process for producing a polyurethane-coated conduit element, the process comprising:

mixing

a) a mixture of aromatic and aliphatic polyisocyanate with,

b) at least one polymeric compound having at least two hydrogen atoms

which are reactive toward isocyanate,

c) one or more chain extenders,

d) a catalyst, and

e) optionally at least one other auxiliary, additive, or both,

to form a reaction mixture;

applying the reaction mixture to a conduit element; and

allowing the reaction mixture to react to form a polyurethane layer,

wherein;

an equivalence ratio of isocyanate groups to a sum of isocyanate-reactive hydrogen atoms ranges from 1;

0.5 to 1;

1.30; and

a chain extender index KV of the reaction mixture calculated according to formula (1);

2. The process according to claim 1, wherein the chain extender index KV is from 30 to 95.

3. The process according to claim 1, wherein the one or more chain extenders c) have a functionality of from 2 to 4 and a hydroxyl number of from 500 to 2500 mg KOH/g.

4. The process according to claim 1, wherein

the aliphatic polyisocyanate in the polyisocyanate mixture a) comprises an isocyanurate-, allophanate- or biuret-modified aliphatic isocyanate, and

a proportion of monomeric aliphatic isocyanates is less than 1% by weight, based on a total weight of the aliphatic polyisocyanate.

5. The process according to claim 4, wherein the isocyanurate-, allophanate-, or biuret-modified aliphatic isocyanate is formed from hexamethylene diisocyanate.

6. The process according to claim 1, wherein the chain extender index KV is from 35 to 85.

7. The process according to claim 1, wherein the at least one polymeric compound b) has a molecular weight of at least 450 g/mol.

8. A process for producing a polyurethane-coated conduit element, the process comprising:

mixing

a) a mixture of aromatic and aliphatic polyisocyanate with,

b) at least one polymeric compound having at least two hydrogen atoms which are reactive toward isocyanate,

c) one or more chain extenders,

d) a catalyst, and

e) optionally at least one other auxiliary, additive, or both,

to form a reaction mixture;

introducing the reaction mixture into a mold;

curing the reaction mixture to form a molding;

removing the molding from the mold; and

applying the molding to a conduit element to form a polyurethane-coating conduit element,

wherein;

an equivalence ratio of isocyanate groups to a sum of isocyanate-reactive hydrogen atoms ranges from 1;

0.5 to 1;

1.30; and

a chain extender index KV of the reaction mixture calculated according to formula (1);

9. The process according to claim 8, wherein the chain extender index KV is from 30 to 95.

10. The process according to claim 8, wherein the one or more chain extenders c) have a functionality of from 2 to 4 and a hydroxyl number of from 500 to 2500 mg KOH/g.

11. The process according to claim 8, wherein

the aliphatic polyisocyanate in the polyisocyanate mixture a) comprises an isocyanurate-, allophanate- or biuret-modified aliphatic isocyanate, and

a proportion of monomeric aliphatic isocyanates is less than 1% by weight, based on a total weight of the aliphatic polyisocyanate.

12. The process according to claim 11, wherein the isocyanurate-, allophanate-, or biuret-modified aliphatic isocyanate is formed from hexamethylene diisocyanate.

13. The process according to claim 8, wherein the chain extender index KV is from 35 to 85.

14. The process according to claim 8, wherein the at least one polymeric compound b) has a molecular weight of at least 450 g/mol.