Silane-functional polymeric polyurethanes

Patent metadata

Field	Value
Publication number	US-10844161-B2
Application number	US-201716323604-A
Country	US
Kind code	B2
Filing date	Aug 8, 2017
Priority date	Aug 9, 2016
Publication date	Nov 24, 2020
Grant date	Nov 24, 2020

Abstract

The invention relates to a method for producing polyurethanes containing silane groups, to products that can be obtained by means of said method, and to the use of said products for producing cross-linkable binders, in particular for coatings, sealant raw materials, or glue raw materials.

First claim

The invention claimed is:

1. A process for preparing silane-containing polyurethanes comprising the reaction of
A) at least one polymeric polyol having an acid number determined according to DIN EN ISO 2114:2002-06 of 0.01 to 30.0 mg KOH/g based on the solids content with
B) at least one compound which has at least one carboxyl-reactive group and contains at least one epoxy group, carbodiimide group and/or 2-oxazoline group to obtain a reaction product and the reaction of the reaction product with
C) at least one alkoxysilane-functional isocyanate.

2. The process as claimed in claim 1 , wherein the polymeric polyol A) is an at least difunctional polymeric polyol having a number-average molecular weight M n of 270 to 22000 g/mol.

3. The process as claimed in claim 1 , wherein the polymeric polyol A) is a polyester polyol, polycarbonate polyol and/or polyacrylate polyol.

4. The process as claimed in claim 1 , wherein the compound B) having at least one carboxyl-reactive group is at least one mono- or polycarbodiimide based on 2,6-diisopropylphenyl isocyanate and/or 1,3,5-triisopropylbenzene-2,4-diisocyanate.

5. The process as claimed in claim 1 , wherein the reaction of the polymeric polyol A) with the at least one compound B) having carboxyl-reactive groups is carried out while maintaining an equivalent ratio of carboxyl groups to carboxyl-reactive groups of 1.5:1 to 1:5.

6. The process as claimed in claim 1 , wherein the employed alkoxysilane-functional isocyanate C) is at least one compound which comprises precisely one isocyanate group and precisely one silane group having at least one alkoxy substituent.

7. The process as claimed in claim 1 , wherein the employed alkoxysilane-functional isocyanate C) is at least one compound of general formula (I)

in which
R 1 , R 2 and R 3 independently of one another represent identical or different saturated or unsaturated linear or branched, aliphatic or cycloaliphatic or optionally substituted aromatic or araliphatic radicals having up to 18 carbon atoms which may optionally contain up to 3 heteroatoms from the group of oxygen, sulfur, nitrogen with the proviso that at least one of the radicals R 1 , R 2 or R 3 is connected to the silicon atom via an oxygen atom and
X represents a linear or branched organic radical having up to 6 carbon atoms.

8. The process as claimed in claim 7 , wherein in the formula (I)
R 1 , R 2 and R 3 independently of one another represent identical or different alkyl radicals having up to 6 carbon atoms and/or alkoxy radicals having up to 6 carbon atoms which may contain up to 3 oxygen atoms with the proviso that at least one of the radicals R 1 , R 2 or R 3 is an alkoxy radical and
X represents a linear or branched organic radical having 1 to 4 carbon atoms.

9. The process as claimed in claim 1 , wherein the employed alkoxysilane-functional isocyanate C) is at least one compound of general formula (II)

which is present in admixture with subordinate amounts of silane-functional compounds of general formula (III),

and wherein
R 1 , R 2 and R 3 independently of one another represent identical or different saturated or unsaturated linear or branched, aliphatic or cycloaliphatic or optionally substituted aromatic or araliphatic radicals having up to 18 carbon atoms which may optionally contain up to 3 heteroatoms from the group of oxygen, sulfur, nitrogen, with the proviso that at least one of the radicals R 1 , R 2 and R 3 is connected to the silicon atom via an oxygen atom,
X represents a linear or branched organic radical having up to 6 carbon atoms, and
Y represents a linear or branched, aliphatic or cycloaliphatic radical having 4 to 18 carbon atoms or an optionally substituted aromatic or araliphatic radical having 6 to 18 carbon atoms and
wherein the compounds of general formula (III) account for a proportion of 2% to 15% by weight of the total mass of the compounds of general formulae (II) and (III).

10. The process as claimed in claim 9 , wherein the alkoxysilane-functional isocyanate C) is at least one reaction product of 3-mercaptopropyltrimethoxysilane and/or 3-mercaptopropyltriethoxysilane with 1,5-diisocyanatopentane, 1,6-diisocyanatohexane, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane, 2,4′- and/or 4,4′-diisocyanatodicyclohexylmethane or a mixture thereof.

11. The process as claimed in claim 1 , wherein the employed alkoxysilane-functional isocyanate C) is at least one compound of general formula (IV)

which is present in admixture with subordinate amounts of silane-functional compounds of general formula (V),

and wherein
R 1 , R 2 and R 3 independently of one another represent identical or different saturated or unsaturated linear or branched, aliphatic or cycloaliphatic or optionally substituted aromatic or araliphatic radicals having up to 18 carbon atoms which may optionally contain up to 3 heteroatoms from the group of oxygen, sulfur, nitrogen, with the proviso that at least one of the radicals R 1 , R 2 and R 3 is connected to the silicon atom via an oxygen atom,
X represents a linear or branched organic radical having up to 6 carbon atoms, and
Y represents a linear or branched, aliphatic or cycloaliphatic radical having 4 to 18 carbon atoms or an optionally substituted aromatic or araliphatic radical having 6 to 18 carbon atoms;
and
wherein the compounds of general formula (V) account for a proportion of 2% to 15% by weight of the total mass of the compounds of general formulae (IV) and (V).

12. The process as claimed in claim 1 , wherein the reaction of the reaction product with the alkoxysilane-functional isocyanate C) is carried out while maintaining an equivalent ratio of isocyanate groups to hydroxyl groups of 0.7:1 to 1.5:1.

13. A silane-containing polyurethane prepared by a process of claim 1 .

14. A method comprising utilizing the silane-containing polyurethanes as claimed in claim 13 for preparing a crosslinkable binder.

15. A crosslinkable binder containing silane-containing polyurethanes as claimed in claim 13 .

Assignees

• Covestro Deutschland Ag

Inventors

• Laas Hans-Josef

Classifications

• C08G18/6258 Primary

  the acid groups being esterified with polyhydroxy compounds or epoxy compounds during or after polymerization · CPC title

• C08G18/683

  containing cyclic groups · CPC title

• C09J175/14

  Polyurethanes having carbon-to-carbon unsaturated bonds · CPC title

• C08G18/797

  containing carbodiimide and/or uretone-imine groups · CPC title

• C08G18/227

  of antimony, bismuth or arsenic · CPC title