MXPA00004073A - Polymer compositions - Google Patents

Abstract

The open time of a cementitious composition, such as a grout, may be increased by the incorporating therein, as a binder, a polymer composition comprising a film-forming copolymer formed by polymerization of a monomer mixture comprising 1 to 3%of at least one monomer selected from the group of monomers consisting of amides of a,b-unsaturated C3 to C6 carboxylic acids and N-vinyl lactams, and at least one hydroxy-(C1 to C8)alkyl (meth)acrylate monomer, wherein the total amount of these monomers is from 2 to 7.5%by weight of said monomer mixture.

Description

POLYMER COMPOSITIONS This invention relates to polymer compositions. More particularly, although not exclusively, the invention relates to polymer compositions suitable for use as a binder for cementitious slurries Ceramic tile adhesives are widely used to adhere ceramic tiles to substrate, such as walls, floors and bathroom ceilings and kitchens. Once the slabs adhere to the relevant substrate, a grout is often used to fill the spaces between the slabs and thus provide an appropriate finish. These slurries can be cementitious or non-cementitious and can be purchased as a ready-to-use product, a formulated system from a package (non-cementitious) or a two-pack system (cementitious), comprising a wet part that includes a polymer, water and a defoamer and a dry part, which includes the cementitious component. A variant of the two pack system involves the use of a re-dispersible powder polymer. In this case, the polymer, defoamer and g ^^^^ «cement comprises the dry component, while the wet component is only water. Once prepared, the cement slurry soon begins to cure, typically within 45 minutes of first mixing the cementitious component with the water. It is the curing of the grout that leads to a hard seal, impervious to water, between the slabs. The process of applying the grout is a manual process, carried out by professionals or DIY enthusiasts. If a professional or a DIY enthusiast, such as artisans, at least occasionally experience the need to have to place unused cement slurry, which was left before the craftsman had the opportunity to use it. This is particularly so when, for example, the craftsman has to leave the prepared slurry unused for a prolonged period of time, such as after lunch, or leave the slurry applied to a substrate for too long, before completing the appropriate task, such as in the case of a grout, before smoothing it to be flush with the surface of the slab. -. , -, -, -, t-,, ___ --- __ ^ ________ MaMM ____ M ____ MjtMg || MMM8a | Mj | th ^ The time that the grout takes to cure at a certain point count can no longer be worked, it is a measure of its time open. For example, a slurry with an open time of 45 minutes, can be worked up for 45 minutes after its preparation before its performance becomes damaged due to its cure. In other words, the grout can be used for up to 45 minutes after its preparation, before it becomes unable to work and has to be discarded. It is desirable that the grout has a very large open time, thus reducing unnecessary waste, but this should be tempered by the requirement that the grout cure sufficiently quickly for the bathroom or kitchen to be available for use within a period of time. of short time, after the placement of the slabs has been completed. Typically, the kitchen or bathroom should be able to be used within 24 hours after completing the placement of the slabs. Therefore, within 24 hours of application, the grout should be sufficiently hard and waterproof. , «--_ - __-_. -.__ ^ __.

The curing properties of the adhesive or cementitious slurry are controlled primarily by the process of hydration and crystallization between the cement and the water in the mixture. However, it is known that the curing regime can be affected by the nature of the polymeric binder used in the adhesive or slurry mixture. The binders used in adhesives or grouts of ceramic slabs are typically based on polymer compositions in which the polymer is a copolymer formed from a mixture of monomers, comprising at least two monomers selected from the slurry comprising, (meth) acrylates of alkyl (C x to C 8), (meth) acrylic acid and styrene. The compositions of aqueous polymers, commercially available, which are formed from a mixture of monomers, as described above, and which are promoted for use in adhesives and grouts of ceramic slabs, include Rhoplex FM-8814K, Rhoplex E-330, Rhoplex-2200, Rhoplex MC-76 and Rhoplex MC-1834, from Rhom and Haas Company and Acronal S-400 from BASF AG. Cement slurries formulated with these binders tend to have open times of the order of 40 to 50 minutes and cure sufficiently after 24 hours of application. To obtain economies of scale, manufacturers prefer to produce polymers that can be sold for use in various applications and formulators prefer to buy polymers that they can formulate into several different products. For example, it is preferred if a new polymer, primarily produced for use in a cementitious slurry, can also be used as a binder in a ceramic tile adhesive, cementitious or non-cementitious, a coating, such as a cementitious paint or not. Cement, or a mastic. In this way, the potential market for the new polymer is significantly increased. However, this is only true if the properties of the final product are not adversely affected in the replacement or replacement of an old polymer with the new polymer. In the most preferred situation, the new polymer is not only equal in performance to the old polymer, but also somewhat better in that performance.

EP-A-0810274 discloses binders useful in low-emission coatings, such as plasters, slab and paint slurries, especially low-emission dispersion paints, and offer improved resistance to wet abrasion. The binders comprise at least one aqueous dispersion of polymer having a minimum film-forming temperature of less than 10 ° C and prepared by aqueous radial emulsion polymerization of a mixture of monomers comprising: a) from 45 to 70 parts by weight of at least one monomer, whose homopolymer has a glass transition temperature (Tg) of less than 20 ° C, b) 30 to 55 parts by weight of at least one monomer, whose homopolymer has a higher Tg 50 ° C, c) from 0 to 1 part by weight of at least one monomer with acid groups, and d) from 0 to 2 parts by weight of at least one extra monomer, selected from C3 to C6 carboxylic acid amides, a , ß-unsaturated, their esters of hydroxy-C2 to C6 alkyl and / or N-vinyl lactams, with the proviso that the total parts by weight of a) plus b) add up to 100 parts by weight.

It is an object of the present invention to provide polymer compositions which are suitable for use in or as binders in cementitious slurries and which, once formulated in these slurries, are capable of contributing to an increased open time without detrimentally affecting any other expected property. of the slurry. Preferably, the polymer compositions can be used in other fields of application. In accordance with the present invention, a polymer composition comprising a film-forming copolymer is provided, preferably at a Tg of -40 to +30 ° C, obtained by the polymerization of a monomer mixture comprising: a.) minus one monomer selected from the group consisting of alkyl (meth) acrylates (C x to C 1), styrene, substituted styrenes, acrylonitrile, butadiene, isoprene, isobutylene, ethylene, propylene, vinyl acetate and other vinyl esters of carboxylic acids (Cx to C12), such as W-9 and W-10, from Shell Chemical Company, and Vinate 2-EH, from Union Carbide; b.) 1 to 3% by weight of the mixture of at least one monomer selected from the group consisting of C3 to C6, a, β-unsaturated carboxylic acid amides, and N-vinyl lactams; c. ) at least 1% by weight of the mixture of at least one hydroxy (C to C8) alkyl (meth) acrylate), in which the total amount of b) and c) constitutes from 2 to 7.5%, preferably from 2 to 6. %, more preferably from 2 to 5%, by weight of the monomer mixture, and d.) from 0 to 1% by weight of the monomer mixture of at least one polymerizable compound, comprising acid functional groups.

In another aspect of the present invention, a method is provided for increasing the opening time of a cementitious composition, comprising an aqueous polymer composition including a film-forming copolymer, preferably with a Tg of -40 to + 30 ° C. , obtained by the polymerization of a mixture of monomers, comprising: a.) at least one monomer selected from the group consisting of alkyl (meth) acrylates (C to C18), cycloalkyl (meth) acrylates (C5 to C10) , styrene, substituted styrenes, acrylonitrile, butadiene, isoprene, isobutylene, ethylene, propylene, vinyl acetate and other vinyl esters of carboxylic acids. { Cx to C12, such as the W-9 and W-10, "of Shell Chemical Company and Vinate 2-EH, of Union Carbide; b.) from 0 to 1% by weight of the monomer mixture of at least one polymerizable compound comprising acid functional groups; this method comprises incorporating within the monomer mixture, prior to its polymerization: c.) from 1 to 3% by weight of the mixture of at least one monomer, selected from the group consisting of carboxylic acid amides C3 to C6, , ß-unsaturated and N-vinyl lactams; and d.) at least 1% by weight of the mixture of at least one hydroxy-alkyl (meth) acrylate (Cx to C8); wherein the total amount of c) and d) constitutes from 2 to 7.5%, preferably from 2 to 6%, more preferably from 2 to 5%, by weight of the monomer mixture.

In yet another aspect of the present invention, the use is provided for increasing the open time of a formulated aqueous cementitious composition of a polymer composition, comprising a film-forming copolymer, preferably having a Tg of -40 to +30 °. C, obtained by the polymerization of a monomer mixture comprising: a.) At least one monomer selected from the group consisting of alkyl (meth) acrylates (Cx to C1S), styrene, substituted styrenes, acrylonitrile, butadiene, isoprene, isobutylene, ethylene, propylene, vinyl acetate and other vinyl esters of carboxylic acids (CL to C12), such as W-9 and W-10, from Shell Chemical Company, and Vinate 2-EH, from Union Carbide; b.) 1 to 3% by weight of the mixture of at least one monomer selected from the group consisting of C3 to C6, a, β-unsaturated carboxylic acid amides, and N-vinyl lactams, - c.) at least 1% by weight of the mixture of at least one hydroxy-alkyl (meth) acrylate. { Cx to C8), in which the total amount of b) and c) constitutes 2 to 7.5%, preferably 2 to 6%, more preferably 2 to 5%, by weight of the monomer mixture, and d.) Of 0 to 1% by weight of the monomer mixture of at least one polymerizable compound, comprising acid functional groups.

Surprisingly, it has been found that the cementitious formulated aqueous composition, comprising the polymer compositions of the present invention, such as a slurry, can have an increased open time, compared to conventional formulated compositions, and that this can be accomplished without any significant detrimental effect on the other properties of the material of the formulated composition. The film-forming copolymer is obtained by the polymerization of a monomer mixture, comprising at least one monomer selected from the group of monomers consisting of alkyl (meth) acrylates (C x to C 18), preferably alkyl (meth) acrylates ( C4 to C18), cyclo (C5 to C10) alkyl (meth) acrylates, styrene, substituted premieres, preferably styrene substituted by alkyl (Cx to C4), halogenated or non-halogenated, acrylonitrile, butadiene, isoprene, butadiene, isoprene, isobutylene, ethylene, propylene and vinyl acetate and other vinyl esters of carboxylic acids. { Cx to C12), such as the W-9 and W-10 of Shell Chemical Company, and Vinate 2-EH, of Union Carbide. Preferably, the group of monomers consists of butyl acrylate, n-octyl acrylate 2-ethylhexyl acrylate, n-decyl-acrylate, lauryl acrylate, stearyl acrylate, isobornyl acrylate, methyl methacrylate, ethyl methacrylate. , butyl methacrylate, isobutyl methacrylate, 2-ethylhexyl methacrylate, n-decyl methacrylate, lauryl methacrylate, stearyl methacrylate, isobornyl methacrylate, dibutyl maleate, monobutyl maleate, phosphoethyl methacrylate, sulfoethyl methacrylate, styrene , we are replaced by alkyls. { C1 to C4), acrylonitrile methacrylonitrile, vinyl acetate and other vinyl esters of carboxylic acids (Cx to C12), such as W-9 and W-10 of Shell Chemical Company, and Vinate 2-EH of Union Carbide, butadiene, isoprene, ethylene and propylene. More preferably, the monomer group consists of butyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, stearyl acrylate, isobornyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, isobutyl methacrylate, methacrylate 2, -ethylhexyl, lauryl methacrylate, stearyl methacrylate, methacrylate, isobornyl, styrene, vmiltoluene, a-methyl-styrene, acrylonitrile and meta-nitrile. More preferably, the monomer group consists of butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, styrene and acrylonitrile. The above monomers should be present in the monomer mixture preferably in an amount of up to 98%, more preferably 50 to 98% and even more preferably 70 to 98% by weight of the mixture. More preferably, acrylonitrile is present in the monomer mixture in an amount of up to 5%, preferably 0 to 3.5% by weight of the mixture. The film-forming copolymer is obtained by the polymerization of a monomer mixture comprising from 1 to 3% by weight of the mixture of at least one monomer, selected from the group of monomers consisting of the carboxylic acid amides C3 to Cs a , ß-unsaturated and the N-vinyl lactams. Preferably, the monomer group consists of amides of the C3 to C6 α, β-unsaturated carboxylic acids and N-vinyl pyrrolidone, more preferably (meth) acrylamide, N-methylol- (meth) acrylamide and N-vinyl- pyrrolidone. Acrylamide is the most preferred monomer. Preferably, the film-forming copolymer is obtained by the polymerization of a monomer mixture comprising at least 1%, preferably 1 to 4%, more preferably 1 to 3% by weight of the mixture of at least one hydroxy-alkyl (meth) acrylate. { C to C8).

More preferably, the monomer group consists of 2-Hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate. The most preferred monomer is 2-hydroxyethyl methacrylate). Preferably, the film-forming copolymer is obtained by the polymerization of a monomer mixture comprising from 0 to 1%, preferably from 0.05 to 0.75%, more preferably from 0.1 to 0.5%, by weight of the mixture of at least one polymerizable compound that includes acid groups. Preferably, the compound comprises at least one ethylenically unsaturated group and at least one acid group. More preferably, the compound is at least one monomer selected from the group of monomers consisting of the carboxylic acids (C3 to C6), a, β-unsaturated, dicarboxylic acids (C4 to C8), α, β-unsaturated, and aryl acids or (C2 to C8) alkyl-sulfonic, monoethylenically unsaturated. Preferably, the group of monomers consists of acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, methacrylic anhydride, maleic anhydride, itaconic anhydride, vinyl sulphonic acid, methallyl sulphonic acid, vinylbenzenesulphonic acid, styrene-sulfonic acid, acrylamido-ethanesulfonic acid, acrylamido-2-methylpropanesulfonic acid, 2-sulfoethyl (meth) acrylate and 2-sulfopropyl (meth) acrylate. Acrylic acid and methacrylic acid are the most preferred monomers. In addition to monomers a), b), c) and d), as defined above, the monomer mixture that is polymerized to produce the copolymer forming the film may comprise other polymerizable monomers, (e). These additional monomers can, once polymerized, contribute functionally to promote entanglement, adhesion, water resistance, resistance to pick up dirt, or to resist film more. Examples of monomers that can contribute to functionality include the polymerizable monomers containing a siloxane group, such as vinyl trialkoxysilane, for example, vinyltrimethoxysilane or vinyltriethoxysilane, alkylvinyl-dialkoxysilanes, (meth) acryloxyalkyl trialkoxy- silanes, for example (meth) acryloxypropyltrimethoxysilane, vinyltrichlorosilane, (meth) acryloxyethyl-methyldialkoxy-silanes, (meth) acryloxypropyl-methyldialkoxysilanes and vinyltris (beta-methoxyethoxy) silane and / or acetoxy (meth) acrylates -alkyl (C1 to C4), such as acetoacetoxy-ethyl methacrylate. The monomers which can contribute functionally (monomer (e)) can be present in the monomer mixture in a total amount of 0.05 to 20%, preferably 0.05 to 10%, more preferably 0.01 to 5%, by weight of the mixture of monomers. Monomers that contribute non-functionally can be present in ..__ -_- < -! «'- * - > - < -_-- > ._ a total amount of up to 20%, preferably up to. 10%, by weight of the total mixture. The polymer composition of the present invention may be an aqueous dispersion or solution of the copolymer described above. Preferably, the composition is an aqueous dispersion of the copolymer particles, this dispersion is preferably formed by the emulsion polymerization of the relevant monomers. Alternatively, the polymer composition may be in the form of a dry powder. In one embodiment, the film-forming copolymer can be a polymer obtained by the aqueous emulsion polymerization of a monomer mixture consisting of 68.3% butyl acrylate, 25.9% styrene, 1.5% acrylamide, 2% methacrylate, hydroxyethyl, 2% acrylonitrile and 0.3% methacrylic acid. In another embodiment, the copolymer forming the film can be a polymer formed by the aqueous emulsion polymerization of a monomer mixture consisting of 74.1% butyl acrylate, 20.1% isobornyl methacrylate, 1.5% acrylamide, 2% of hydroxyethyl methacrylate, 2% acrylonitrile and 0.3% methacrylic acid. In yet another modality, the film-forming copolymer can be a polymer formed by the aqueous emulsion polymerization of 68.3% butyl acrylate, 25.9% ethyl acrylate, 1.5% acrylamide, -2% hydroxyethyl methacrylate, 2% acrylonitrile and 0.3% acrylic acid. The polymer compositions are useful in or as binders for adhesives and grouts of cementitious ceramic slabs. They may also be useful in or as binders for other formulated compositions, which may or may not comprise a cementitious component. Such other formulated compositions include coatings, such as top coatings for interiors and exteriors, basic and sizing coatings, other adhesives, such as construction adhesives, pressure sensitive adhesives and wood gums, mastics, caulks, sealants, mortar concrete marches, self-leveling mortars, waterproof membranes, exterior insulation and finishing systems (EIFS) and aqueous pastes and roof tile coatings, and as binders in textiles, non-woven fabrics and paper. In addition to demonstrating increased open time in the cementitious formulated compositions, the polymer compositions of the present invention can also demonstrate improved adhesion properties in certain formulated compositions. For example, ceramic tile adhesives, comprising the aqueous polymer composition of the present invention, can demonstrate improved adhesion in concrete, ceramic or wood substrates, and mastics comprising the polymer composition of the present invention can demonstrate a improved adhesion in concrete and metal substrates. Depending on the particular application of the formulated compositions, which comprise the polymer compositions of the present invention, the copolymer preferably has a Tg in the approximate range of -50 to + 30 ° C, more preferably -40 to +30 ° C. C. When the formulated composition is cementitious, the copolymer preferably has a Tg in the range of -50 to +25 ° C. In the case where the composition ll i i "^ -» ***** - *. formulated to be a ceramic slab adhesive, slurry, water impermeable membrane, mastic, caulking or sealant, the copolymer preferably has a Tg in the approximate range of -30 to 10 ° C. When * the formulated composition is a pressure sensitive adhesive, the copolymer preferably has a Tg in the range of -50 to -20 ° C. When the formulated composition is a paint or sizing, the copolymer has a Tg in the approximate range of -10 to +30 ° C. When the polymer composition is a binder for paper applications, the film-forming copolymer will typically have a Tg in the range of 0 to +25 ° C, and when it is a binder for textile and non-woven products, the copolymer which Shape films will typically have a Tg in the range of -40 to + 20 ° C. For EIFS applications, the copolymer that forms the film will typically have a Tg in the range of -20 to +15 ° C. The Tg is determined by differential scanning calorimetry (DSC), measured at a heating rate of 3CC per minute, with the Tg taken at the midpoint of the transition.

The present invention will now be described more specifically in terms of the following examples of some of the preferred embodiments, which are provided for purposes of illustration only and may be contrasted with the comparative tests, also given below. In the following examples, reference is made to the following test procedures: Open Time: Open time is used as a measure of compatibility between the cement and the emulsion polymer modifier. The objective is to ensure that the modified mortar has enough compatibility with the cement to allow its use in a convenient time interval. Generally speaking, larger open times are preferred to the point where they extend to such an extent that they perform the setting time. The test is carried out by preparing a modified polymer slurry. The grout is mixed manually and checked in its working capacity every 5 minutes up to 30 minutes, and then every 10 minutes up to 2 hours elapsed time. After 2 hours, the working capacity is checked every 15 minutes. 24 Hour Compression: The purpose of the compression force measurement is to indicate the early development of resistance or, in other words, the degree of setting delay. The procedure involves the preparation of duplicate cubes of 5 cm, of modified mortar, using the procedure described in the ASTM C-109 standard (American Society for Testing and Materials). The test specimens were demoulded immediately before testing on a Tinus Olsen test apparatus, capable of delivering a force of 45,360 kg. Adhesion of quarry to wood, 7 days: The purpose of this evaluation is the measurement of the adhesive strength of a ceramic tile adhesive mortar between a quarry slab of low porosity and the wood, difficult to adhere to the substrate. The procedure used for this test is described in ANSÍ 118.4 (American National Standard Institute) for the quarry slab. The load rate used was 1089 kg / minute in the Tinius Olsen test apparatus. Adhesion of dry wall slab, 7 days: The adhesion strength in 7 days of a highly modified ceramic slab adhesive mortar showed the performance on a high porosity substrate of a glazed ceramic wall slab. The procedure used for this test is described in ANSÍ 118.4 for the wall slab. The transverse separation regime was 2.54 cm / minute in the Tinius Olsen test apparatus. Adhesion of wet wall slab 7 days / 7 days of drying: The purpose of this test is to measure adhesion strength retention under humid conditions and conducted using the protocol described for the 7-day dry test. After the slab sets were cured for 7 days, under dry conditions, they were submerged in water for 7 more days. Elongation to Rupture and Maximum / Rupture Stress: In addition to testing the properties of cementitious formulations, the purpose of this test is to measure the mechanical properties of a waterproof, non-cementitious membrane. The mechanical properties of the membrane were evaluated using the voltage tester Tinus Olson. A piece of film, in the form of a bobbin (ASTM D412 Type C) was cut out, and the central part was 2.54 cm in length and 6.35 cm in width. This was stretched at a rate of 5.08 cm per minute and the stress / strain curve was recorded. In general, the strongest and most elongated films are convenient, and the compositions of Examples 18-22 actually have a higher maximum strength and greater elongation at break in comparative form. In the Table, the values are given in MPa, except for the elongation, which is given in percentage.

Example 1 An aqueous polymer composition, comprising a copolymer of the composition: 67.7 BA / 30.8 St / l.5 AM / BA = butyl acrylate; St = styrene; AM = acrylamide) was prepared according to the following procedure. A stirred reactor, containing 490 grams of deionized water, was heated to 87 ° C. To this were added 65 grams of a preformed polymer emulsion, which contains 45% solids, with a particle size of 100 nm and 6.71 grams of sodium persulfate. Over the next four hours, an emulsion of monomers obtained was added of up to 230.0 g of deionized water, 21.2 g of a 23% solution of sodium dodecylbenzenesulfonic acid, 602.4 g of styrene, 1324.1 g of butyl acrylate and 29.35 g of acrylamide, while maintaining the reaction temperature of the copper at 86 ° C. A solution of 2.88 g of sodium persulfate in 250 g of water was added simultaneously to the reactor. After adding 60% of the monomer emulsion, 95.4 g of a preformed polymer emulsion with 41% solids content, with a particle size of 60 nm, were added to the reactor. After the addition of the monomer emulsion was complete, the remaining traces of the monomer were polymerized by reducing the temperature of the copper to 75 CC and adding to the reactor an aqueous solution of 0.01 g of ferrous sulfate heptahydrate in 5 g of water, 1.51 g of t-butyl hydroperoxide in 4 grams of water and 1.29 g of formaldehyde of sodium sulfoxylate in 28 g of water. After holding the reactor for a period of time, 6.1 g of t-butyl hydroperoxide in 16 g of water were added to the reactor, followed by the addition of 5.18 g of sodium sulfoxylate formaldehyde in 112 g of water. The reactor was then cooled to 50 ° C and 20.95 g of a 70% solution of an alkyl alcohol ethoxylate with 40 units of ethylene oxide in 50 g of water were added to the reactor, followed by 6 g of a solution 50% sodium hydroxide in 50 grams of water. The Kathon LX product (Rohm and Haas biocide) was added followed by dilution with water, to give an emulsion with 56.0% solids content, with a pH of 8.5, a viscosity of 132 centipoises and a Tg of -7 ° C. Examples 2 to 9 Substantially by the same procedure as for Example 1, described above, the aqueous compositions of polymers 2 to 9 were prepared, comprising the copolymers with the following compositions: Example 2: 67.8 BA / 30.4 St / l.5 AM / 0.3 MAA (MAA = methacrylic acid). Note that corresponds to Example 2 of the patent EP-A-0810274. The resulting emulsion had a solids content of 56.0%, a pH of 7.4 and a Tg of -5 ° C, Example 3: 67.6 BA / 30.4 St / l.5 AM / 0.5 HEMA (HEMA = hydroxyethyl methacrylate). The resulting emulsion had a solids content of 56.2%, a pH of 8.8 and a Tg of -5 ° C.

Example 4: 67.7 BA / 30 ST / l.5 AM / 0.5 HEMA / 0.3 MAA. The resulting emulsion had a solids content of 56.2%, a pH of 7.5 and a Tg of -7 ° C.

Example 5: 67.2 BA / 29.3 St / l.5 AM / 2 HEMA. The resulting emulsion had a solids content of 56.3%, a pH of 8.0 and a Tg of -5 ° C.

Example 6: 67.4 BA / 28.8 St / l.5 AM / 2 HEMA. The resulting emulsion had a solids content of 56.2%, a pH of 7.5 and a Tg of -4 ° C.

Example 7: 68.1 BA / 26.4 St / l.5 AM / 2 HEMA / 2 AN (AN = acplonitrile). The resulting emulsion had a solids content of 56.1%, a pH of 8.9 and a Tg of -8 ° C.

Example 8: 68.3 BA / 25.9 St / l.5 AM / 2 HEMA / 2 AN /? 3 MAA. The resulting emulsion had a solids content of 56.1%, a pH of 7.5 and a Tg of -7 ° C.

Example 9: 68.3 BA / 25.9 St / l.5 AM / 2 HEMA / 2 AN / 0.3 AA (AA = acrylic acid). The resulting emulsion had a solids content of 55.9%, a pH of 6.6 and a Tg of -5 ° C.

Example 10: Polymerization was carried out as in Example 1, except that the monomer emulsion consisted of 1294.74 g of butyl acrylate, 586.74 g of styrene, 39.12 g of hydroxyethyl acrylate, 29.34 g of acrylamide and 5.87 g of methacrylic acid, and the amount of sodium persulfate used was 8.49 g in the initial reactor charge and 3.64 g in the co-charge. Additionally, the polymerization was carried out at 84 ° C. The resulting emulsion had a solid content of 50%, a pH of 6.6 and a Tg of -4 ° C.

Example 11: Polymerization was carried out as in Example 10, except that the monomer composition was 36.2 BA / 30.0 LMA / 30 St / 2 HEMA / 1.5 AM / 0.3 MAA (LMA = lauryl methacrylate), and 9.8 g of methyl-beta-cyclodextrin were added in the initial charge of the reactor, with the deionized water. The resulting emulsion had a solids content of 57.1%, a pH of 6.4 and a Tg of -8 ° C.

Example 12: Polymerization was carried out as in Example 10, except that the monomer composition was 66 BA / 30 ST / 2 HEMA / 1.5 AM / 0.5 AA oligomer. The oligomeric AA species terminally used had a weight average molecular weight (Mw) of 1199 and a number average molecular weight (Mn) of 485. The resulting emulsion had a solids content of 56.0%, a pH of 4.9 and a Tg of -3 ° C.

Example 13: An aqueous composition of polymers, comprising a copolymer of the composition: 67.2 BA / 14.3 ST / 15 MMA / 1 AM / 2 HEMA / 0.5 MAA (MMA = methyl methacrylate) was prepared according to the following procedure. A stirred reactor, containing 600 g of deionized water - was heated to 85 ° C. To this was added 7.00 g of sodium persulfate and 65.5 g of a preformed polymer emulsion, with 45% solids content, with a particle size of 100 nm. In the next four hours, a monomer emulsion composed of 200.00 g of deionized water, 21.3 g of a 23% solution of sodium dodecylbenzenesulfonic acid, 279.6 g of styrene, 1314 g of butyl acrylate, 293. 4 g of methyl methacrylate, 19.55 g of acrylamide, 39.1 g of HEMA and 9.8 g of methacrylic acid were added in 4 hours, while the reaction temperature of the copper was maintained at 84 ° C. A solution of 2.3 g of sodium persulfate in 120 g of water was added simultaneously to the reactor. After 60% of the monomer emulsion had been added, 93 g of a preformed polymer emulsion with 41% solids content, with a particle size of 60 nm, were added to the reactor. After the addition of monomer emulsion was complete, the remaining traces of the monomer were polymerized by reducing the temperature of the copper to 75 ° C and adding to the reactor an aqueous solution of 0.02 g of ferrous sulfate heptahydrate in 15 g of water and 11.2 g of t-butyl hydroperoxide in 20 g of water. Then the formaldehyde of sodium sulfoxylate (5.8 g dissolved in 150 g of water) was added. The reactor was then cooled to 50 ° C and 28 g of a 70% solution of an alkyl alcohol ethoxylate with 40 units of ethylene oxide in 50 g of water were added to the reactor, followed by 6 g of a solution at 50% sodium hydroxide in 50 g of water, the dilution with water gave an emulsion with a content of 58.6% solids, with a pH of 7.0, a viscosity of 246 centipoises and a Tg of -10 ° C.

Examples 14 to 22 Depending on the test to be performed, each of the polymer compositions, prepared in Examples 1 to 9, were combined in the formulations described below: Open Time (formulation of grout mortar) Dry Components 200 g 60 mesh sand (local sand) 100 g Portland cement, Type I (gray) Liquid Components 20 g Emulsion polymer (based on dry weight) 43 g Water 0.2 g Nopco NXZ defoamer, available from Henkel Corp.

Compressive Strength, 24 hours (patch mortar formulation) Dry Components 750 g ASTM C-109 Sand 300 g Portland Cement, Type A (gray) Liquid Component 30 g Emulsion Polymer (based on dry weight) 145.5 g Water 0.3 g Defoamer Nopco NXZ Adhesion of Quarry to Wood, 7 days (Adhesive Mortar of Ceramic Slabs) Dry Components 180 g Sand mesh 60 120 g Portland Cement, Type I (gray) 1.2 g Cellulose Thickener Liquid Components 24 g Emulsion Polymer (dry basis) 60 g Water 0.24 g Nopco NXZ Adhesion 7 days dry and 7 days dry / 7 days wet (Ceramic Slab Adhesive) Dry Components 180 g Sand, mesh 60 120 g Portland Cement, Type I (gray) 1.2 g Cellulose Thickener Liquid Components 60 g Emulsion Polymer (base dry) 60 g Water 0.35 g Nopco NXZ Elongation to Rupture and Maximum Stress Strength / Rupture (water proof membranes): Grinding 30.6 g water 2.8 g Nopco NXZ 5.8 g Tamol 731, available from Rohm and Haas CO. 13.6 g TiONA RCL 575, available from Millennium Inorganic Chemicals 111.2 g of Omycarb 10, available from Omya (California), Inc 41.2 g Omycarb 2, available from Omya (California), Inc.

After mixing the milling at high speed in a Cowles dissolving apparatus, the milling was diluted with 200 g of 56% solids emulsion, 1.2 g of Acrysol SCT 275, available from Rohm and Haas CO., And 2 grams of Nopco NXZ. The formulations prepared in Examples 14 to 22 were then tested according to the respective test procedures, described below. In addition, as a comparison, a commercially available binder, Aronal S-400, sold by BASF AG, for use in ceramic tile and grouts adhesives, was formulated as before and tested. The results of these tests are shown in Table 1. It can be seen from Table 1 that the slurry formulations in Examples 18-22, each comprise the polymer compositions of the present invention, Examples 5 to 9 showed a significant improvement in open time, when compared to cement slurry formulations based on the comparative formulations and the other copolymers of Examples 1 to 4. This was achieved without significantly affecting the other properties expected for cement slurries. . In addition, it is shown in Table 1 that the other cementitious and non-cementitious formulations, based on the polymer compositions of the present invention, demonstrated a good balance of performance characteristics, which enables them as a broad application base for polymers.

Table 1 15

Claims (9)

R E I V I N D I C L I O N E S

1. A polymer composition, comprising a film-forming copolymer, obtained by the polymerization of a monomer mixture, which comprises: a.) At least one monomer selected from the group consisting of alkyl (meth) acrylates. { C to C18), cyclo (C5 to C10) alkyl (meth) acrylates, styrene, substituted styrenes, acrylonitrile, butadiene, isoprene, isobutylene, ethylene, propylene, vinyl acetate and other vinyl esters of carboxylic acids A to C12 ); b.) 1 to 3% by weight of the mixture of at least one monomer selected from the group consisting of C3 to C6, a, β-unsaturated carboxylic acid amides, and N-vinyl lactams; c.) at least 1% by weight of the mixture of at least one hydroxy-alkyl (meth) acrylate (Cx to C8), in which the total amount of b) and c) constitutes from 2 to 7.5%, by weight of the monomer mixture, and d.) from 0 to 1% by weight of the monomer mixture of at least one polymerizable compound, comprising acid functional groups.

2. A composition, as claimed in claim 1, wherein the monomer mixture comprises up to 98% by weight of the monomers a).

3. A composition, as claimed in claim 1, wherein the monomer mixture comprises a), at least one monomer selected from the group of monomers consisting of butyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate , n-decyl acrylate, lauplo acrylate, stearyl acrylate, isobornyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, isobutyl methacrylate, 2-ethylhexyl methacrylate, n-decyl methacrylate, lauryl methacrylate Stearl metacrylate, isobornyl methacrylate, dibutyl maleate, phosphoethyl methacrylate, sulfoethyl methacrylate, styrene, styrenes substituted by alkyl (Cx-C4), acrylonitrile, methacrylonitrile and vinyl acetate, and other carboxylic acid esters ( CLC ^).

4. A composition, as claimed in claim 3, wherein the monomer mixture a) up to 98% by weight of the mixture of at least one monomer selected from the group of monomers consisting of butyl acrylate, 2-ethylhexyl acrylate , methyl methacrylate and styrene, and from 0 to 3.5% by weight of the acrylonitrile mixture.

5. A composition, as claimed in claim 1, wherein the monomer mixture comprises .b) from 1 to 3% by weight of the mixture of at least one monomer selected from the group consisting of (meth) acrylamide, N- methylol- (meth) acrylamide and N-vinyl pyrrolidone.

6. A composition, as claimed in claim 1, wherein the monomer mixture comprises c) from 1 to 3% by weight of the mixture of at least one monomer selected from the group consisting of 2-hydroxyethyl (meth) acrylate and 2-Hydroxypropyl (meth) acrylate.

7. A composition, as claimed in claim 1, wherein the monomer mixture comprises d) from 0.1 to 0.5% by weight of the mixture of at least one monomer selected from the group consisting of (meth) acrylic acid.

8. A method for increasing the opening time of an aqueous cement composition, this method comprises a polymer composition including a film-forming copolymer, obtained by the polymerization of a monomer mixture comprising: a.) At least one selected monomer of the group consisting of alkyl (meth) acrylates (Cx to C18), (meth) acrylates of cycloalkyl (Cs to C10), styrene, substituted styrenes, acrylonitrile, butadiene, isoprene, isobutylene, ethylene, propylene, vinyl acetate and other vinyl esters of carboxylic acids (Cx to C12; b.) from 0 to 1% by weight of the monomer mixture of at least one polymerizable compound comprising acid functional groups; this method comprises incorporating within the monomer mixture, prior to its polymerization: c.) from 1 to 3% by weight of the mixture of at least one monomer, selected from the group consisting of carboxylic acid amides C3"to C6, a, ß-unsaturated and N-vinyl lactams, and d) at least 1% by weight of the mixture of at least one hydroxy-alkyl (meth) acrylate (Cx to C8), in which the total amount of c) and d) constitutes from 2 to 7.5%, preferably from 2 to 6%, more preferably from 2 to 5%, by weight of the monomer mixture.

9. The use of a polymer composition, as claimed in claim 1, to increase the opening time of a cement composition.