Pulverulent primer composition

Abstract

The present invention relates to primer compositions in powder form that comprise a dispersion powder based on an acrylate polymer having a glass transition temperature in the range from 50 C. to +30 C. and cement. The compositions of the invention are notable for good water barrier effect, good dust-binding capacity, and a low tendency toward salt efflorescence. The compositions find use in the priming of masonry, concrete, rendered surfaces, abraded render, plaster surfaces, wall blocks, wood, and ceramic tiles. They can also be used as adhesion promoters with nonabsorbent substrates such as glazed ceramic or glass tiles, metal surfaces, or surfaces of plastic.

Claims

1. A primer composition in powder form, comprising a) 87.5 to 93.75 wt % of a dispersion powder based on a polymer having a glass transition temperature Tg of from 50 C. to +30 C., comprising: monomer units derived from a first monomer, which is at least one selected from the group consisting of an ester of an ,-ethylenically unsaturated C.sub.3-C.sub.6 monocarboxylic acid or C.sub.4-C.sub.8 dicarboxylic acid with a C.sub.3-C.sub.12 alkanol, wherein the first monomer optionally comprises up to 30 wt % of a C.sub.1-C.sub.2 alkanol ester, and units derived from a second monomer, copolymerizable with the first monomer, wherein the second monomer is a vinylaromatic compound, and b) 6.25 to 12.5 wt % of cement, wherein a weight ratio of the dispersion powder to the cement is of from 7:1 to 15:1.

2. The primer composition according to claim 1, wherein the polymer additionally comprises units derived from a third monomer, copolymerizable with the first and second monomers, and wherein the third monomer is at least one selected from the group consisting of an ,-ethylenically unsaturated C.sub.3-C.sub.6 monocarboxylic acid or C.sub.4-C.sub.8 dicarboxylic acid, (meth)acrylamide, a N,N-mono-di-C.sub.1-C.sub.4-alkyl(meth)acrylamide, (meth)acrylonitrile, a N-vinyl derivative of a cyclic lactam, a hydroxy-C.sub.2-C.sub.4-alkyl (meth)-acrylate, and a N,N-mono- or di-C.sub.1-C.sub.4-alkylaminoalkyl(meth)acrylate.

3. The primer composition according to claim 1, wherein the polymer additionally comprises units derived from fourth monomer, copolymerizable with the first, second and third monomers, and wherein the fourth monomer is a compound comprising at least two nonconjugated, ethylenic double bonds.

4. The primer composition according to claim 1, wherein the first monomer is at least one selected from the group consisting of n-propyl acrylate, methyl ethyl acrylate, n-butyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-hexyl methacrylate, and 2-ethylhexyl methacrylate.

5. The primer composition according to claim 2, wherein the third monomer is at least one selected from the group consisting of acrylamide, methacrylamide, acrylic acid, methacrylic acid, acrylonitrile, methacrylonitrile, 2-acrylamido-2-methylpropanesulfonic acid, vinylpyrrolidone, hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, and hydroxypropyl methacrylate.

6. The primer composition according to claim 3, wherein the fourth monomer is selected from the group consisting of butadiene, ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, 1,3-butylene and 1,4-butylene glycol di(meth)acrylate, 2,2-dimethylpropylene glycol di(meth)acrylate, divinyl maleate, diallyl maleate, divinyl fumarate, diallyl fumarate, divinyl phthalate, diallyl phthalate, divinylbenzene, cyclopentadienyl acrylate, cyclopentadienyl methacrylate, cyclohexenyl acrylate and cyclohexenyl methacrylate, tricyclodecenyl acrylate and tricyclodecenyl methacrylate, N,N-divinylimidazolin-2-one, and triallyl cyanurate.

7. The primer composition according to claim 1, wherein the polymer comprises units derived from 50 to 85 wt % of the first monomer.

8. The primer composition according to claim 1, wherein the cement is at least one selected from the group consisting of blast furnace cement, oil shale cement, Portland cement, white cement, hydrophobized Portland cement, rapid-setting cement, high-expansion cement and high-alumina cement.

9. The primer composition according to claim 8, wherein the cement has an Fe.sub.2O.sub.3 content of less than 5 wt %, based on a total mass of the cement.

10. The primer composition according to claim 9, wherein the cement is a white cement.

11. The primer composition according to claim 1, wherein the polymer has a glass transition temperature Tg of 30 C. to +15 C.

12. The primer composition according to claim 1, further comprising: an auxiliary.

13. The primer composition according to claim 9, comprising a polymer or oligomer comprising a functional group selected from the group consisting of a sulfonic acid group, a carboxylic acid group and salts thereof.

14. A method for priming an absorbent substrate, the method comprising: priming the absorbent substrate with the primer composition according to claim 1.

15. An adhesion promoter for promoting adhesion with at least one nonabsorbent substrate, wherein the adhesion promotor comprises the primer composition according to claim 1.

Description

EMBODIMENTS OF THE INVENTION

(1) 1. A primer composition in powder form, comprising

(2) a) a dispersion powder based on an acrylate polymer having a glass transition temperature Tg from 50 C. to +30 C. and

(3) b) cement,

(4) the weight ratio of dispersion powder to cement being in the range from 5:1 to 30:1.

(5) 2. The composition of embodiment 1, wherein the weight ratio of dispersion powder to cement is in the range from 5:1 to 21:1.

(6) 3. The composition of embodiment 2, wherein the weight ratio of dispersion powder to cement is in the range from 7:1 to 15:1.

(7) 4. The composition of any one of the preceding embodiments, wherein the polymer comprises monomer units of

(8) a1) at least one monomer selected from the esters of ,-ethylenically unsaturated C.sub.3-C.sub.6 monocarboxylic acids or C.sub.4-C.sub.8 dicarboxylic acids with C.sub.3-C.sub.12 alkanols.

(9) 5. The composition of embodiment 4, wherein the monomer is selected from esters of acrylic acid, methacrylic acid, maleic acid, fumaric acid, or itaconic acid.

(10) 6. The composition of embodiment 5, wherein the monomer is selected from esters of acrylic acid, methacrylic acid and mixtures thereof.

(11) 7. The composition of embodiment 4 or 5, wherein the monomer is selected from propyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, decyl (meth)acrylate, or dodecyl (meth)acrylate, dimethyl maleate, di-n-butyl maleate, and di-n-butyl fumarate.

(12) 8. The composition of embodiment 7, wherein the monomer is selected from n-butyl acrylate, 2-ethylhexyl acrylate, and mixtures thereof.

(13) 9. The composition of any one of embodiments 4 to 8, wherein the ester monomer optionally comprises up to 30 wt % of C.sub.1-C.sub.2 alkanol ester.

(14) 10. The composition of embodiment 9, wherein the ester monomer optionally comprises up to 20 wt % of C.sub.1-C.sub.2 alkanol ester.

(15) 11. The composition of embodiment 10, wherein the ester monomer optionally comprises up to 10 wt % of C.sub.1-C.sub.2 alkanol ester.

(16) 12. The composition of embodiment 4 to 8, wherein the ester monomer does not comprise a C.sub.1-C.sub.2 alkanol ester.

(17) 13. The composition of any one of the preceding embodiments, wherein the polymer additionally comprises units of

(18) a2) at least one other monomer, copolymerizable with the monomer (a1) and selected from vinylaromatic compounds and vinyl or allyl esters of C.sub.1-C.sub.12 carboxylic acids.

(19) 14. The composition of embodiment 13, wherein the monomer is selected from vinylaromatic compounds.

(20) 15. The composition of embodiment 13 or 14, wherein the monomer is selected from styrene, carboxylated styrene, sulfonated styrene, -methylstyrene, or vinyltoluenes, such as o-vinyltoluene.

(21) 16. The composition of embodiment 13, wherein the monomer is selected from vinyl and allyl esters.

(22) 17. The composition of embodiment 16, wherein the monomer is selected from vinyl acetate, vinyl propionate, vinyl n-butyrate, vinyl laurate, and vinyl stearate, and also allyl acetate, allyl propionate, allyl n-butyrate, allyl laurate, and allyl stearate.

(23) 18. The composition of any one of the preceding embodiments, wherein the polymer additionally comprises units of

(24) a3) at least one other monomer, copolymerizable with the monomer (a1) and (a2) selected from ,-ethylenically unsaturated C.sub.3-C.sub.6 monocarboxylic acids or C.sub.4-C.sub.8 dicarboxylic acids, (meth)acrylamide, N,N-mono- and di-C.sub.1-C.sub.4-alkyl(meth)acrylamides, (meth)acrylonitrile, N-vinyl derivatives of cyclic lactams, hydroxy-C.sub.2-C.sub.4-alkyl (meth)-acrylates, and N,N-mono- and di-C.sub.1-C.sub.4-alkylaminoalkyl (meth)acrylates.

(25) 19. The composition of embodiment 18, wherein the monomer (a3) is selected from acrylamide, methacrylamide, acrylic acid, methacrylic acid, acrylonitrile, methacrylonitrile, 2-acrylamido-2-methylpropanesulfonic acid, vinylpyrrolidone, hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, or hydroxypropyl methacrylate.

(26) 20. The composition of embodiment 19, wherein the monomer (a3) is selected from (meth)acrylic acid, (meth)acrylamide, (meth)acrylonitrile, hydroxyethyl (meth)acrylate, and hydroxypropyl (meth)acrylate.

(27) 21. The composition of any one of the preceding embodiments, wherein the polymer additionally comprises units of

(28) (a4) at least one further monomer, copolymerizable with the monomers (a1), (a2), and (a3), which is selected from compounds which comprise at least two nonconjugated, ethylenic double bonds.

(29) 22. The composition of embodiment 21, wherein the monomer (a4) is selected from the diesters of dihydroxy compounds with ,-ethylenically unsaturated C.sub.3-C.sub.6 monocarboxylic acids, the vinyl and allyl esters of C.sub.4-C.sub.8 dicarboxylic acids, divinylbenzene, cyclopentadienyl acrylate and methacrylate, cyclohexenyl acrylate and methacrylate, tricyclodecenyl acrylate and methacrylate, N,N-divinylimidazolin-2-one, butadiene, and triallyl cyanurate.

(30) 23. The composition of embodiment 21, wherein the monomer (a4) is selected from ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, 1,3-butylene and 1,4-butylene glycol di(meth)acrylate, glycidyl (meth)acrylate, 2,2-dimethylpropylene glycol di(meth)acrylate, divinyl maleate, diallyl maleate, divinyl fumarate, diallyl fumarate, divinyl phthalate, diallyl phthalate, and divinylbenzene.

(31) 24. The composition of any one of the preceding embodiments, wherein the polymer comprises

(32) (a1) units of esters of acrylic acid or methacrylic acid or a mixture thereof with a C.sub.3-C.sub.12 alkanol, preferably a C.sub.3-C.sub.8 alkanol, or a mixture thereof,

(33) (a2) units of styrene,

(34) (a3) units of acrylamide or methacrylamide or a mixture thereof,

(35) (a4) optionally units of a crosslinking monomer (a4).

(36) 25. The composition of any one of the preceding embodiments, wherein the polymer comprises units of 50 to 85 wt % of the monomer (a1), based in each case on the total monomer amount.

(37) 26. The composition of any one of the preceding embodiments, wherein the polymer comprises units of 15 to 50 wt % of the monomer (a2), based in each case on the total monomer amount.

(38) 27. The composition of any one of the preceding embodiments, wherein the polymer comprises units of 0.5 to 15 wt % of the monomer (a3), based in each case on the total monomer amount.

(39) 28. The composition of any one of the preceding embodiments, wherein the polymer comprises units of 0.1 to 10 wt % of the monomer (a4), based in each case on the total monomer amount.

(40) 29. The composition of any one of the preceding embodiments, wherein the polymer comprises units of

(41) 50 to 80 wt % of the monomer (a1),

(42) 15 to 40 wt % of the monomer (a2),

(43) 0.5 to 15 wt % of the monomer (a3), and

(44) 0 to 10 wt % of the monomer (a4),

(45) based in each case on the total monomer amount.

(46) 30. The composition of any one of the preceding embodiments, wherein the polymer comprises units of

(47) 60 to 80 wt % of the monomer (a1),

(48) 15 to 30 wt % of the monomer (a2),

(49) 0.5 to 10 wt % of the monomer (a3), and

(50) 0 to 5 wt % of the monomer (a4),

(51) based in each case on the total monomer amount.

(52) 31. The composition of embodiment 21, wherein the polymer comprises units of 60 to 80 wt % of the monomer (a1), selected from n-butyl acrylate, 2-ethylhexyl acrylate and mixtures thereof,

(53) 15 to 30 wt % of the monomer (a2) selected from styrene and vinyl acetate,

(54) 0.5 to 10 wt % of the monomer (a3) selected from acryl amide, methacryl amide, acrylic acid, methacrylic acid and mixtures thereof, and

(55) 0 to 5 wt % of the monomer (a4),

(56) based in each case on the total monomer amount.

(57) 32. The composition of any one of the preceding embodiments, wherein the polymer has a glass transition temperature Tg of 30 C. to +15 C.

(58) 33. The composition of embodiment 32, wherein the polymer has a glass transition temperature Tg of 20 C. to +5 C.

(59) 34. The composition of any one of the preceding embodiments, wherein the cement is selected from blast furnace cement, oil shale cement, Portland cement, white cement, hydrophobized Portland cement, rapid-setting cement, high-expansion cement, high-alumina cement, and mixtures thereof.

(60) 35. The composition of embodiment 34, wherein the cement has an Fe.sub.2O.sub.3 content of less than 5 wt %, based on the total mass of the cement.

(61) 36. The composition of embodiment 34 or 35, wherein the cement is white cement.

(62) 37. The composition of any one of the preceding embodiments obtainable by preparing an aqueous dispersion of the polymer, subjecting the polymer dispersion to drying and admixing the dried polymer powder with cement.

(63) 38. The composition of any one of the preceding embodiments in the form of an aqueous dispersion.

(64) 39. The composition of embodiment 38, obtainable by redispersing the composition of any one of embodiments 1 to 32.

(65) 40. The composition of any one of the preceding embodiments, further comprising auxiliaries such as defoamers, thickeners, fillers, natural or synthetic fibers, drying assistants, or antiblocking agents.

(66) 41. The composition of embodiment 40, comprising as drying assistant a polymer or oligomer comprising a functional group selected from sulfonic acid and carboxylic acid group and the salts thereof.

(67) 42. The composition of embodiment 40, wherein the polymer or oligomer is a condensate of formaldehyde with naphthalene sulfonic acid, melamine sulfonic acid, phenol sulfonic acid, lignin sulfonic acid, homo or copolymers of 2-acrylamido-2-methylpropane sulfonic acid and the salts thereof.

(68) 43. The composition of embodiment 41 or 42 comprising 1 to 40 wt % of the polymer or oligomer, based on the total weight of the polymer.

(69) 44. The use of the composition of any of the preceding embodiments for priming absorbent substrates, such as masonry, concrete, rendered surfaces, abraded render, plaster surfaces, wall blocks, wood, and ceramic tiles.

(70) 45. The use of the composition of any of embodiments 1 to 43 as an adhesion promoter with nonabsorbent substrates, such as glazed ceramic or glass tiles, metal surfaces, or surfaces of plastic.