Waterproofing membrane
View Patent ↗Disclosed is a waterproofing membrane that comprises a carrier sheet, a pressure sensitive adhesive layer on one surface of the carrier sheet, and a protective coating layer on the adhesive layer. The protective coating layer comprises a highly reflective protective coating layer operative to bond to concrete cast against it, particularly one that is produced from an aqueous coating comprising an acrylic emulsion, a filler, and a white pigment. The pigment volume concentration of the filler plus white pigment is greater than or equal to 40% by volume. The protective coating layer protects the membrane against weather exposure, tolerates foot traffic and strongly adheres to concrete cast against it. The protective coating comprises an acrylic polymer with a unique multi-domain morphology (i.e., at least two distinct polymer domains).
1. A waterproofing membrane in the form of a sheet-like laminate comprising:
a carrier sheet, a pressure sensitive adhesive layer on one surface of the carrier sheet, and a protective coating layer on the adhesive layer, wherein the protective coating layer has a penetration ≦20 dmm (ASTM D5), and a reflectivity ≧55%, measured by a reflectometer perpendicular to a surface illuminated at a 45° angle, and wherein the protective coating layer comprises an acrylic polymer with two or more distinct polymer domains, including a first polymer domain and a second polymer domain, wherein (a) the first polymer domain is softer than the second polymer domain, and/or (b) the first polymer domain has a lower glass transition temperature (Tg) than the glass transition temperature of the second polymer domain.
2. The waterproofing membrane of claim 1 wherein the first polymer domain and the second polymer domain are in a core/shell arrangement.
3. The waterproofing membrane of claim 2 wherein the shell incompletely encapsulates the core or wherein the shell surrounds a multiplicity of cores.
4. The waterproofing membrane of claim 2 wherein the core is the harder second polymer domain.
5. The waterproofing membrane of claim 4 wherein the second polymer domain is cross-linked.
6. The waterproofing membrane of claim 1 wherein the second polymer domain comprises discrete areas within a continuous network of the first polymer domain.
7. The waterproofing membrane of claim 6 wherein the second polymer domain is cross-linked.
8. The waterproofing membrane of claim 1 wherein the second polymer domain comprises polymeric nanoparticles.
9. The waterproofing membrane of claim 1 wherein the acrylic polymer includes the first polymer domain and the second polymer domain within an individual polymer particle.
10. The waterproofing membrane of claim 1 wherein the acrylic polymer comprises about 50-95% of the first polymer domain and about 5-50% of the second polymer domain.
11. The waterproofing membrane of claim 1 wherein the first polymer domain and the second polymer domain form an interpenetrating or semi-interpenetrating network.
12. The waterproofing membrane of claim 1 wherein the first polymer domain has a Tg of 0° C. to −50° C.
13. The waterproofing membrane of claim 12 wherein the second polymer domain has a Tg of 10° C. to 80° C.
14. The waterproofing membrane of claim 1 wherein the acrylic polymer comprises Rhoplex™ 2438.
15. The waterproofing membrane of claim 13 wherein the protective coating layer has a coating weight of 10 g/m 2 to 200 g/m 2 .
16. The waterproofing membrane of claim 13 wherein the protective coating layer has a textured surface and has a coating weight of 60 g/m 2 to 400 g/m 2 .
17. The waterproofing membrane of claim 1 wherein the protective coating layer additionally comprises a filler and a white pigment, wherein the pigment volume concentration of the filler plus white pigment is 40% to 90% based on total solids.
18. The waterproofing membrane of claim 17 wherein the pigment volume concentration of the filler plus white pigment is 50% to 80% based on total solids.
19. The waterproofing membrane of claim 1 additionally comprising a releasable bonding layer on the protective coating layer, wherein the releasable bonding layer comprises a water soluble polymer, an alkali soluble polymer, or a homopolymer or copolymer of polyvinyl acetate.
20. The waterproofing membrane of claim 19 wherein the releasable bonding layer comprises a polymer selected from the group consisting of polyvinyl alcohol (PVOH), polyethylene oxide (PEO), water soluble cellulosic polymers including hydroxypropyl methyl cellulose and hydroxyethyl cellulose, hydrolyzed maleic anhydride polymers and copolymers, polyvinylpyrrolidone, sulfonated polystyrene, polysulfoethyl acrylate, poly(2-hydroxyethylacrylate), polyacrylamide, poly(acrylic acid) and alkali metal salts thereof, natural or synthetically modified polysaccharides, proteins, alginates, xanthan gums, and guar gums, styrene maleic anhydride copolymers, copolymers of acrylic acid and styrene and/or alpha-methyl styrene, hydroxypropyl methylcellulose acetate succinate, copolymers of methacrylic acid and methylmethacrylate, acrylic acid-ethyl acrylate-methyl methacrylate copolymer, a copolymer of ethyl acrylate, methylmethacrylate, and acrylic acid, rosin acid, and homopolymers or copolymers of polyvinyl acetate.
21. The waterproofing membrane of claim 19 wherein the releasable bonding layer comprises a homopolymer of polyvinyl acetate.
22. The waterproofing membrane of claim 19 wherein the releasable bonding layer additionally comprises nanoscale silica in an amount of 30% to 70% by volume of the silica plus polymer.
23. The waterproofing membrane of claim 22 wherein the nanoscale silica has a particle size of 5 nm to 30 nm.
24. The waterproofing membrane of claim 23 wherein the releasable bonding layer has a coating weight of 1 g/m 2 to 15 g/m 2 .
25. The waterproofing membrane of claim 1 wherein the protective coating layer additionally comprises a filler and a white pigment, wherein the pigment volume concentration of the filler plus white pigment is 40% to 90% based on total solids, and wherein the membrane additionally comprising a releasable bonding layer on the protective coating layer, wherein the releasable bonding layer has a coating weight of 1 g/m 2 to 15 g/m 2 and comprises nanoscale silica and a binder.
26. The waterproofing membrane of claim 25 wherein the binder comprises a homopolymer of polyvinyl acetate, and wherein the nanoscale silica is present in an amount of 30% to 70% by volume of the silica and binder.
27. A method of waterproofing a concrete structure comprising: applying to a building substrate or concrete form the waterproofing membrane of claim 1 comprising a carrier sheet, a pressure sensitive adhesive layer on one surface of the carrier sheet, and a protective coating layer on the adhesive layer, wherein the protective coating layer has a penetration ≦20 dmm (ASTM D5), and a reflectivity ≧55%, measured by a reflectometer perpendicular to a surface illuminated at a 45° angle, and wherein the protective coating layer comprises an acrylic polymer with two or more distinct polymer domains, including a first polymer domain and a second polymer domain, wherein (a) the first polymer domain is softer than the second polymer domain, and/or (b) the first polymer domain has a lower glass transition temperature (Tg) than the glass transition temperature of the second polymer domain; and casting concrete against the membrane of claim 1 .
28. A waterproofing membrane in the form of a sheet-like laminate comprising:
a carrier sheet, a pressure sensitive adhesive layer on one surface of the carrier sheet, and a protective coating layer on the adhesive layer, wherein the protective coating layer has a penetration ≦20 dmm (ASTM D5), and a reflectivity ≧55%, measured by a reflectometer perpendicular to a surface illuminated at a 45° angle, and wherein the protective coating layer comprises an acrylic polymer with two or more distinct polymer domains, including a first polymer domain and a second polymer domain, wherein (a) the first polymer domain is softer than the second polymer domain, and/or (b) the first polymer domain has a lower glass transition temperature (Tg) than the glass transition temperature of the second polymer domain; and
the waterproofing membrane further comprising a releasable bonding layer on the protective coating layer, wherein the releasable bonding layer comprises a water soluble polymer, an alkali soluble polymer, or a homopolymer or copolymer of polyvinyl acetate.
29. The waterproofing membrane of claim 28 wherein the releasable bonding layer comprises a polymer selected from the group consisting of polyvinyl alcohol (PVOH), polyethylene oxide (PEO), water soluble cellulosic polymers including hydroxypropyl methyl cellulose and hydroxyethyl cellulose, hydrolyzed maleic anhydride polymers and copolymers, polyvinylpyrrolidone, sulfonated polystyrene, polysulfoethyl acrylate, poly(2-hydroxyethylacrylate), polyacrylamide, poly(acrylic acid) and alkali metal salts thereof, natural or synthetically modified polysaccharides, proteins, alginates, xanthan gums, and guar gums, styrene maleic anhydride copolymers, copolymers of acrylic acid and styrene and/or alpha-methyl styrene, hydroxypropyl methylcellulose acetate succinate, copolymers of methacrylic acid and methylmethacrylate, acrylic acid-ethyl acrylate-methyl methacrylate copolymer, a copolymer of ethyl acrylate, methylmethacrylate, and acrylic acid, rosin acid, and homopolymers or copolymers of polyvinyl acetate.
30. The waterproofing membrane of claim 29 wherein the releasable bonding layer comprises a homopolymer of polyvinyl acetate.
31. The waterproofing membrane of claim 29 wherein the releasable bonding layer additionally comprises nanoscale silica in an amount of 30% to 70% by volume of the silica plus polymer.
32. The waterproofing membrane of claim 31 wherein the nanoscale silica has a particle size of 5 nm to 30 nm.
33. The waterproofing membrane of claim 32 wherein the releasable bonding layer has a coating weight of 1 g/m 2 to 15 g/m 2 .