Liquid-applied waterproofing membrane for roofs comprising a long-chain aldimine

Patent metadata

Field	Value
Publication number	US-10487237-B2
Application number	US-201414762349-A
Country	US
Kind code	B2
Filing date	Jan 21, 2014
Priority date	Jan 22, 2013
Publication date	Nov 26, 2019
Grant date	Nov 26, 2019

Abstract

The present invention describes a one-part moisture-curing liquid-applied waterproofing membrane having a polyurethane polymer, a long-chain aldimine and a hardener selected from an oxazolidine and another aldimine. The membrane has a low viscosity at low solvent content and a good shelf life stability and cures fast to form a solid elastic material. The membrane is particularly suitable for roofing applications, possessing high strength, high elongation and good durability under outdoor weathering conditions in a broad temperature range.

First claim

The invention claimed is:

1. A one-part moisture-curing liquid-applied waterproofing membrane comprising:
at least one isocyanate-functional polyurethane polymer;
at least one aldimine of the formula (I),

wherein
m is 2 or 3,
A is a divalent or a trivalent hydrocarbyl moiety of average molecular weight in a range of 800 to 4,000 g/mol containing ether groups, and
Z is a monovalent C 3 to C 30 hydrocarbyl moiety; and
at least one hardener which is an oxazolidine or an aldimine different from formula (I), wherein a ratio between a number of aldimino groups from aldimines of the formula (I) and a number of isocyanate-reactive groups from oxazolidines and aldimines different from formula (I) is in a range of 2/98 to 40/60.

2. The membrane according to claim 1 , wherein A is a divalent or a trivalent hydrocarbyl moiety of average molecular weight in a range of 1,000 to 3,000 g/mol containing oxyethylene units and/or 1,2-oxypropylene units.

3. The membrane according to claim 1 , wherein the aldimine of the formula (I) is an aldimine of the formula (I a),

wherein
R 1 and R 2 are the same or different C 1 to C 12 linear or branched alkyls, or are joined together to form a divalent linear or branched C 4 to C 12 hydrocarbyl moiety which is part of a 5- to 8-membered carbocyclic ring;
R 3 is hydrogen or a linear or branched C 1 to C 12 alkyl or arylalkyl or alkoxycarbonyl; and
X is a monovalent moiety of the formulae

wherein
R 4 and R 5 are the same or different linear or branched C 1 to C 20 alkyls or cycloalkyls or aralkyls optionally containing ether groups, or are joined together to form a divalent linear or branched C 4 to C 12 hydrocarbyl moiety which is part of a 5- to 8-membered heterocyclic ring which, besides the nitrogen atom, may contain an ether or thioether or tertiary amino group, and R 6 is hydrogen or a monovalent C 2 to C 20 hydrocarbyl moiety.

4. The membrane according to claim 1 , wherein the aldimine of the formula (I) is selected from the group consisting of: N,N′-bis(2,2-dimethyl-3-(N-morpholino)-propylidene)-polyoxypropylenediamines with an average molecular weight in a range of 1,300 to 4,400 g/mol, N,N′-bis(2,2-dimethyl-3-lauroyloxypropylidene)-polyoxypropylenediamines with an average molecular weight in a range of 1,500 to 4,600 g/mol, N,N′,N″-tris(2,2-dimethyl-3-(N-morpholino)-propylidene)-polyoxypropylenetriamines with an average molecular weight in the range of 3,000 to 4,000 g/mol, N,N′,N″-tris(2,2-dimethyl-3-lauroyloxypropylidene)-polyoxypropylenetriamines with an average molecular weight in a range of 3,300 to 4,300 g/mol, N,N′-bis(2,2-dimethyl-3-(N-morpholino)-propylidene)-polyoxyethylene-polyoxypropylenediamines with an average molecular weight in a range of 2,000 to 2,600 g/mol, and N,N′-bis(2,2-dimethyl-3-lauroyloxypropylidene)-polyoxyethylene-polyoxypropylenediamines with an average molecular weight in a range of 2,200 to 2,900 g/mol.

5. The membrane according to claim 1 , wherein the at least one hardener is an aldimine of the formula (III),

wherein
n is 2 or 3, and
G is a divalent or trivalent hydrocarbyl moiety of molecular weight in a range of 28 to 500 g/mol optionally containing ether or urethane groups.

6. The membrane according to claim 5 , wherein the aldimine of the formula (III) is an aldimine of the formula (III a)

7. The membrane according to claim 6 , wherein in the at least one aldimine of the formula (III a), X is N-morpholino.

8. The membrane according to claim 5 , wherein in the at least one aldimine of the formula (III), Z is phenyl.

9. The membrane according to claim 6 , wherein in the at least one aldimine of the formula (III a), X is lauroyloxy.

10. The membrane according to claim 1 containing 100 g VOC per liter or less.

11. A method for waterproofing a roof, comprising:
applying the membrane according to claim 1 in a liquid state on at least a surface of the roof; and
curing the membrane.

12. Waterproofing system, consisting of:
optionally a primer and/or an undercoat;
one or more than one layer of the membrane according to claim 1 , in combination with a fibre reinforcement mesh; and
optionally a top coat.

13. Method of waterproofing a roof structure, comprising:
applying the membrane according to claim 1 in liquid state onto a substrate of the roof structure in a layer thickness in a range of 0.5 to 3 mm;
contacting the membrane with a fibre reinforcement mesh within an open time of the membrane;
exposing the membrane to moisture to thereby cure the membrane partially or fully to obtain an elastic coating; and
optionally applying a second layer of the membrane according to claim 1 in a layer thickness in a range of 0.5 to 3 mm and curing it by exposure to moisture.

14. The membrane according to claim 1 , wherein Z contains ether.

15. The membrane according to claim 3 , wherein R 6 contains ether, carbonyl, or both.

16. The membrane according to claim 3 , wherein the aldimine of the formula (I) is selected from the group consisting of: N,N′-bis(2,2-dimethyl-3-(N-morpholino)-propylidene)-polyoxypropylenediamines with an average molecular weight in a range of 1,300 to 4,400 g/mol, N,N′-bis(2,2-dimethyl-3-lauroyloxypropylidene)-polyoxypropylenediamines with an average molecular weight in a range of 1,500 to 4,600 g/mol, N,N′,N″-tris(2,2-dimethyl-3-(N-morpholino)-propylidene)-polyoxypropylenetriamines with an average molecular weight in a range of 3,000 to 4,000 g/mol, N,N′,N″-tris(2,2-dimethyl-3-lauroyloxypropylidene)-polyoxypropylenetriamines with an average molecular weight in a range of 3,300 to 4,300 g/mol, N,N′-bis(2,2-dimethyl-3-(N-morpholino)-propylidene)-polyoxyethylene-polyoxypropylenediamines with an average molecular weight in the range of 2,000 to 2,600 g/mol, and N,N′-bis(2,2-dimethyl-3-lauroyloxypropylidene)-polyoxyethylene-polyoxypropylenediamines with an average molecular weight in a range of 2,200 to 2,900 g/mol.

17. The membrane according to claim 16 , wherein the at least one hardener is an aldimine of the formula (III),

wherein
n is 2 or 3, and
G is a divalent or trivalent hydrocarbyl moiety of molecular weight in a range of 28 to 500 g/mol optionally containing ether or urethane groups.

18. The membrane according to claim 1 , wherein the membrane has a Brookfield viscosity in the range of 2,000 to 15,000 mPa·s.

Assignees

• Sika Tech Ag

Inventors

• Burckhardt Urs
• Stadelmann Ursula
• Haberle Hans
• Byrne Michael
• Gatrell Mark
• Coward Alexander

Classifications

• C09D175/12

  from compounds containing nitrogen and active hydrogen, the nitrogen atom not being part of an isocyanate group · CPC title

• C08G18/307

  Atmospheric humidity · CPC title

• C08G18/755 Primary

  and at least one isocyanate or isothiocyanate group linked to a secondary carbon atom of the cycloaliphatic ring, e.g. isophorone diisocyanate · CPC title

• Y10T442/10

  Scrim [e.g., open net or mesh, gauze, loose or open weave or knit, etc.] · CPC title

• C08G18/12 Primary

  using two or more compounds having active hydrogen in the first polymerisation step · CPC title