NO803738L - NEW POLYMER PRODUCTS SUITABLE FOR INTERVENTION IN HYDRAULIC BINDING AGENTS - Google Patents

Abstract

1. Claims for the contracting States : BE, CH, LI, DE, FR, GB, IT, NL, SE Compositions which can be used in particular as adjuvants for mixtures based on hydraulic binders, characterised in that they comprise, by way of essential constituents : (a) a mixture of at least two aqueous dispersions of different vinyl polymers, chosen from at least two of the groups comprising : - the latices (designated by : latices A) which result from the copolymerisation of a monomer of the aromatic hydrocarbon type, containing from 8 to 14 carbon atoms and one or two bonds of ethylenic character, with a monomer of the acrylic or methacrylic type, which can be an acid, an ester of this acid with saturated aliphatic or cycloaliphatic alcohols having up to 8 carbon atoms, or a nitrile, an amide or an anhydride derived from this acid ; - the latices (designated by : latices B) which result from the copolymerisation of a monomer of the aromatic hydrocarbon type, containing from 8 to 14 carbon atoms and one or two bonds of ethylenic character, with a monomer of the diethylenic aliphatic hydrocarbon type, containing from 4 to 14 carbon atoms ; - the latices (designated by : latices C) which result from the homopolymerisation of a monomer chosen from the group comprising the vinyl esters of saturated aliphatic acids or of aromatic acids having up to 10 carbon atoms ; and - the latices (designated by : latices D) which result from the copolymerisation of at least two vinyl esters chosen from amongst those mentioned for the latex C ; and (b) an aqueous solution containing either a water-reducing agent or a mixture of a water-reducing agent with a water-soluble salt derived from an oxygen-containing, mineral or carboxylic monoacid or polyacid, at least one of the acid groups of which has an ionisation constant pKa, in water at 25 degrees C, of less than 2.5. 1. Claims for the Contracting State : AT Use of a composition obtained by mixing : (a) 10 to 95% by weight of at least two aqueous dispersions of different vinyl polymers, containing 30 to 60% of dry polymers and chosen from at least two of the groups comprising : - the latices (designated by : latices A) which result from the copolymerisation of a monomer of the aromatic hydrocarbon type, containing from 2 to 14 carbon atoms and one or two bonds of ethylenic character, with a monomer of the acrylic or methacrylic type, which can be an acid, an ester of this acid with saturated aliphatic or cycloaliphatic alcohols having up to 8 carbon atoms, or a nitrile, an amide or anhydride derived from this acid ; - the latices (designated by : latices B) which result from the copolymerisation of a monomer of the aromatic hydrocarbon type, containing from 8 to 14 carbon atoms and one or two bonds of ethylenic character, with a monomer of the diethylenic aliphatic hydrocarbon type, containing from 4 to 14 carbon atoms ; - the latices (designated by : latices C) which result from the homopolymerisation of a monomer chosen from the group comprising the vinyl esters of saturated aliphatic acids or of aromatic acids having up to 10 carbon atoms ; and - the latices (designated by : latices D) which result from the copolymerisation of at least two vinyl esters chosen from amongst those mentioned for the latex C ; and (b) 90 to 5% by weight of a 10-50% strength aqueous solution containing either a water-reducing agent or a mixture of a water-reducing agent with a water-soluble salt derived from an oxygen-containing, mineral or carboxylic monoacid or polyacid, at least one of the acid groups of which has an ionisation constant pKa, in water at 25 degrees C, of less than 2.5, as an adjuvant to be incorporated into mixtures based on hydraulic binders.

Description

The present invention relates to a polymer product particularly suitable as an additive in mixtures based on hydraulic binders, and the distinctive feature of the polymer product according to the invention is that it contains the following essential components: a) A mixture of at least two aqueous dispersions of vinyl polymers, and b) An aqueous solution containing either a water demand reducing agent or a mixture of a water demand reducing agent and a water-soluble salt derived from a monovalent or polyvalent oxygen-containing inorganic acid or carboxylic acid, in which at least one of the acid functions has an ionization constant pKa in water at 25°

C lower than 2.5.

These and other features of the invention appear in the patent claims.

The new synthetic polymer products can be used as additives, for example, for incorporation into mixtures for the production of mortars and concrete on the basis of hydraulic binders for adhesion to building materials consisting of a porous inorganic material such as brick, building stone or concrete, or for incorporation into mixtures for the production of thin mortar on the basis of hydraulic binders used for the production of industrial coatings on the basis of open asphalt pavements.

The term "hydraulic binders" refers to products such as cement and lime which solidifies and hardens in the presence of water to form stable compounds.

The difficulties that arise in getting mortars and fresh concrete to adhere to building materials represent an adhesion problem and this problem is encountered in particular in the following applications: Fixation of fresh mortar or fresh concrete to smooth hardened concrete or old concrete when carrying out over drafts either of the usual type or anti-dust coating, abrasion coating, production of protective plaster and interior and exterior plastering of buildings, repair of damage to all concrete work, reinforced concrete, building stone and brick and erection of masonry work.

One of the purposes of the present invention is to provide new additives which, for mortar or concrete in which they are incorporated, result in good adhesive properties (in the dry state as well as when immersed in water) to building materials and which lead to the following properties: for materials exposed enlarge : air and swelling in water for hardened mortar or concrete, the properties must be equivalent to mortar or concrete without additives (blind test); - and for materials with a strength equivalent to 24 hours and 28 days, these must be significantly improved compared to the blind test.

Another object of the invention is to provide new additives for mortar and concrete which result in less air mixing in commonly used quantities so that their use does not cause disadvantages, especially under the conditions of the mechanical mixing of mortar or concrete, for the mechanical strength and resistance against abrasion of the hardened material.

Another purpose of the invention is to provide new additives which are very effective in the quantities used,

in relation to the binder, so that these are profitable to use.

Other purposes and applications will be apparent from the following description in which:

the term "aqueous dispersion" denotes a mixture containing a continuous phase which consists of water and i

suspension in this aqueous solid particles or droplets of a polymer which is insoluble in water. Such an aqueous dispersion is hereinafter referred to as latex.

the term "vinyl polymer" denotes a macromolecular compound which results from the polymerization of one or more monomers containing at least one carbon-carbon double bond of an ethylene character.

the term "water demand reducer" denotes a product,

soluble in water, which, with a certain degree of workability, allows a reduction of the water content in a certain thin mortar, mortar or concrete or which, with the same water content, particularly increases this workability, or allows the achievement of both of these effects at the same time.

The production of aqueous dispersions of vinyl polymers can be carried out using methods described in the literature. Just as good as preparing a polymer separately and then dispersing it in water, it is more advantageous to use traditional methods for polymerization or copolymerization in emulsion or dispersion and for this you can refer to the following works:

- Schildknecht - Vinyl and Related Polymers -

John Wiley 1952

Bovey a coil. - Emulsion Polymerisation -

Interscience 1955

- Leonard - Vinyl and Diene Monomers - Wiley Interscience.

For the purpose of the invention, the vinyl polymers can be prepared

starting from different monomers and these monomers generally comprise 2 to 14 carbon atoms and one or two ethylenically unsaturated bonds and they can be selected in particular from the following products: unsaturated hydrocarbons of aliphatic nature such as, for example, idea mono-

ethylenically unsaturated hydrocarbons: ethylene, propene, butene, iso-butene or those ethylenically unsaturated hydrocarbons such as butadiene-1,3, methyl-2-butadiene-1,3, dimethyl-2,3-butadiene-1,3, methyl-2-pentadiene -1,3, aromatic hydrocarbons such as e.g. styrene, a- and 6-chlorostyrenes, a- and B-methylstyrenes, methyl-3-styrene, methyl-4-styrene, dimethyl-2,4-styrene, trimethyl-2,4,6-styrene, isopropyl-4- styrene, t-butyl-4-styrene, ortho-, meta- and parasMivinylbenzene, a- and 8-vinylnaphthalene

α-,,-g-unsaturated carboxylic acids which can be used in the production of latex and containing preferably 3 to 6 carbon atoms, such as e.g. acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid, citraconic acid, mesaconic acid, itaconic acid, esters of similar acids with saturated aliphatic or cycloaliphatic alcohols with up to 8 carbon atoms such as e.g. methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, isopropyl acrylate, isopropyl methacrylate, n-butyl acrylate, n-methacrylate, isobutyl acrylate, isobutyl methacrylate, cyclohexyl acrylate, the nitriles, the amides, the anhydrides derived from similar unsaturated acids such as e.g. acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, maleic acid, anhydride

vinyl derivatives such as vinyl chloride, vinylidene chloride,

vinyl esters of saturated aliphatic acids with up to 10 carbon atoms such as e.g. vinyl acetate, vinyl propionate, vinyl butyrate, vinyl laurate or aromatic acids with up to 10 carbons, such as vinyl benzoate.

Among the latexes which can be used in a mixture according to the invention and which are formed from the mentioned monomers, special mention may be made: latex (hereinafter referred to as latex A) which is formed from copolymerization in emulsion or suspension of a monomer of the unsaturated hydrocarbon type of aromatic type with a monomer belonging to the groups of acrylic and meth^acrylic compounds (acids, esters, nitriles, amides or anhydrides)

latex (hereinafter referred to as latex B) which results from the copolymerization of a monomer of the unsaturated hydrocarbon type containing an aromatic cyclic compound with a monomer belonging to the ethylenically unsaturated aliphatic hydrocarbons

latex (hereinafter referred to as latex C) which results from the homopolymerization of a monomer selected from the group of vinyl esters

latex (hereinafter referred to as latex D) which results from the copolymerization of at least two vinyl esters, which

.'e.g. vinyl acetate, vinyl proprionate and vinyl laurate

All of these aqueous dispersions of vinyl polymers or latex generally contain 30 to 60% dry polymer. The amount of the mixture A containing at least two latexes represents 10 to 95 percent by weight of the entire mixture of latex A + aqueous solution B.

Among the mixtures ^a) of latex that can be used in the present invention, preferred binary mixtures are mentioned: latex A + latex B. In this preferred group of mixtures, mixtures are particularly preferred in which: latex A which is obtained from the copolymerization of styrene with one of the following monomers: methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate and containing at least approximately 30% by weight bound styrene (latex hereinafter referred to as latex Al)

latex B is obtained from the copolymerization of styrene with one of the following monomers: butadiene-1,3, methyl-2-butadiene-1,3, dimethyl-2,3-butadiene-1,3 and containing at least about

trained 30% by weight bound styrene (latex hereinafter referred to as latex Bl)

The length of latex A in the mixture latex A + latex B, expressed as the weight ratio latex A/latex B can vary within wide limits and more particularly this quantity can be between 0.5 and 50.

As other mixtures (a) preferred for the production of polymer products according to the invention, ternary mixtures are mentioned: latex A + latex B + latex C. In this preferred group of mixtures, mixtures are particularly preferred in which: latex A has the meaning given above for latex Al

latex B has the meaning given above for latex

Bl

latex C which results from the homopolymerisation of the following vinyl esters: vinyl acetate, vinyl propionate, vinyl butyrate (latex denoted latex Cl).

The amount of latex C usually represents up to 30% by weight of the mixture latex A + latex B + latex C. It is noted that in these ternary mixtures the weight ratio latex A/latex B can vary between those that limit as mentioned earlier for the binary mixtures. The amount of latex C that is preferably used can represent between 4 and 20 percent by weight of the mixture latex A + latex B + latex C.

The second main component (b) of the polymer products according to the invention is an aqueous solution containing either a water demand reducing agent or a mixture of a water demand reducing agent with a water-soluble salt derived from a strongly oxygenated monovalent or polyvalent inorganic acid or carboxylic acid.

The choice of water demand reducing agent depends in particular on its solubility in water. As examples of such agents can be mentioned: the sulphonation products of sulphites or sulphonic acid of resins melamine/formalin (see in particular French patent document 1.510.314

acids obtained by conversion of the equation by means of sulfites or sulfuric acid as well as their water-soluble salts (see in particular US patent document 3,772,045)

- water-soluble salts of convention products obtained by condensation between formaldehyde and sulfonation products from phenol with one or more nuclei (see in particular French patent document 2,182,825)

the alkali salts or the ammonium salts of organic polyvalent acids such as fceks.ppolyvinylsulfonic acid, naphthalene-trisulfonic acid, carbazoletetrasulfonic acid, naphtholtrisulfonic acid (see in particular US patent document 2,905,565)

The water demand reducing agent which is preferably used for the purposes of the invention consists of water-soluble salts of condensation products with a molecular weight between 1500 and 10,000 obtained by condensing formaldehyde with products from sulfonation of aromatic monocyclic or polycyclic condensed aromatic hydrocarbons containing 1 to 12 benzene nuclei.

One can mention as an example the water-soluble salts obtained by condensation with formaldehyde of sulfonation products of aromatic hydrocarbons such as e.g. benzene, nnaphthalene, fluorene, anthracene, phenanthrene, pyrem; in naphthacene, pentacene, hexacene, octacene, nonacene, decacene, undecacene, dodecacene, and the derivatives of these aromatic compounds with 1 to 3 linear or branched alkyl substituents containing 1 to 3 carbon atoms.

The aforementioned condensation products that can be used in the invention are compounds with the formula:

in which:

Ar stands for monocyclic or polycyclic condensed aryl groups containing up to 12 benzene rings, such as those aryl groups derived from aromatic hydrocarbons mentioned above

R^ stands for linear or branched alkyl of 1 to 3 carbon atoms

X stands for a cationic residue of inorganic or organic origin, preferably so that the compound of formula I must be soluble in water

- m is an integer from 0 to 3

n is a number such that an average molecular weight is obtained

between 1,500 and 10,000

As salts of formula I suitable for the production of the polymer blends according to the invention can be mentioned those in which the cationic residues X, connected to sulfonate groups on the aromatic rings, are inorganic cations derived from alkali metals or alkaline earth metals such as lithium, sodium, potassium, calcium, barium or derivatives of metals from the group formed by lead, aluminium, zinc and copper. Ammonium ions NH^<+> or better quaternary ammonium ions with the formula N (R^R^R^R^)"^ in which radicals r^, R^, r^ and R, which can be the same or different each can also be used stands for linear or branched alkyl containing ethyl 1 to 4 carbon atoms.

Among the quaternary ammonium ions can be mentioned tetramethylammonium, tetraethylammonium, methyltriethylammonium, tetrapropylammonium, triethylbutylammonium, tetrabutylammonium.

The salts with formula (I) can also be simple salts and mixed salts obtained by mixing several of the aforementioned cationic residues X.

As salt with formula (I) which can preferably be used for the polymer products according to the invention, those in which:

Ar is a naphthyl group

R^ stands for methyl or ethyl

the cationic residues X which stand for inorganic cations derived from metals such as lithium, sodium, potassium, calcium, barium, ammonium ions NH^<+>, quaternary ammonium ions such as tetramethylammonium ion, tetrapropylammonium, tetrabutylammonium.

Among the preferred salts, the salts of sodium, potassium, calcium, barium, ammonium, tetramethylammonium of the condensation product with a molecular weight between 1500 and 10,000, obtained by condensation with formaldehyde of 3-naphthalene-sulfonic acid are particularly suitable. These salts of the condensation product, with a high molecular weight, of 6-naphthalene-sulfonic acid/formaldehyde are prepared using the method described in US Patent 2,141. 569.

One can likewise use as a water demand reducing agent a mixture comprising a salt of the condensation product with a high molecular weight selected from among those mentioned above, in connection with a water-soluble salt derived from the sulfonation product of aromatic polycyclic condensed hydrocarbons corresponding to the general formula:

in which:

- Ar' represents condensed polycyclic aryl groups containing 2 to 12 benzene nuclei, such as the aryl groups derived from condensed polycyclic aromatic hydrocarbons indicated above under the definition of the symbol Ar

R^, X and m have the meanings indicated above for f

formula (I)

p is a given number either 1 or 2

One can preferably use compounds of formula (II) in which:

Ar' is a naphthyl group

R^ stands for methyl or ethyl

X is a cationic residue that stands for inorganic cation derivatives of lithium, sodium, potassium, calcium, barium, ions NH^<+>, quaternary ammonium ions such as tetramethylammonium, tetrapropylammonium, tetrabutylammonium

- p is an integer equal to 1

The salts of formula (II) can likewise be simple or mixed salts.

The aromatic sulfonic acid which forms the salt of formula (II)

may be the same as that used to prepare the salt of formula (I) by subsequent condensation with formaldehyde.

In a similar case, the salt with formula (II) can optionally be used in whole or in part at the same time as the salt with formula (I), in the form of the intermediate product when the condensation reaction between the aromatic sulfonic acid and HCHO is incomplete and there is an unreacted residue of aromatic sulfonic acid left behind.

In the case where a mixture comprising a

salt of the condensation product with increased molecular weight (I)

and a salt of the sulfonation product (II), the weight ratio of the latter in the mixture is generally not more than 5%.

The aqueous solution (b) may, in addition to the water demand reducing agent, contain a water-soluble salt derived from an oxygen-containing strong monovalent or polyvalent inorganic acid or carboxylic acid and the following derivatives can be mentioned as usable salts: inorganic oxyacids such as nitric acid, sulfuric acid, sulfur acid, phosphoric acid, orthophosphoric acid, pyrophosphoric acid and chromic acid

- carboxylic acids such as cyanoacetic acid, cyanopropionic acid, maleic acid, oxalic acid, orthonitrobenzoic acid

The cationic part of these salts is not critical when they satisfy the condition of ice water solubility of these products. Alkali metal salts and ammonium salts are usually used.

Among these salts, sodium sulphate, sodium nitrate and sodium oxalate are particularly suitable.

The aqueous solution (b) generally comprises 10 to 50 percent by weight of the dry product(s) (water demand reducing agent + possibly the salt of a strong inorganic acid or carboxylic acid). When the aqueous solution (b) comprises a salt of a strong inorganic acid or carboxylic acid, the amount by weight of the latter in the mixture of dry products is at most 25%.

The amount of aqueous solution (b) usually represents 5

to 90% by weight of the entire mixture of latex (.a) + aqueous solution (b).

For the production of the polymer products according to the invention, the order of addition of the essential ingredients is

parts (a) and (b) not critical. The various industrially accepted mixer nodes can be used.

It is noted that the various components which are generally used in the field of related technology with hydraulic binders can be connected without disadvantages to the products according to the present invention during their manufacture or when they are used. Among these ingredients can be mentioned auxiliaries such as fillers and/or pigments (iron filings, asbestos fibres, glass fibres, talc, titanium oxide and kaolin as examples), vidéce emulsifiers of an ionic or non-ionic character, plasticisers such as e.g. dibutyl phthalate, tricresyl phosphate, thickeners such as e.g. carboxymethyl cellulose, methyl cellulose, ethyl cellulose, alkali metal and alkaline earth metal alginates, antigel agents, antifoam agents such as silicone products, dialkyl phosphates containing 15 to 20 carbon atoms, and fungicides. Some of these auxiliaries, especially the emulsifiers and softeners, can be present in all or parts of the polymer products according to the invention as additives for ... the latex used.

The polymer products corresponding to the invention are suitable for

all types of hydraulic binders, especially cement, hydraulic

slaked lime, lime mortar, artificial lime, mixtures of cement and hydraulic lime or lime mortar, or gypsum.

The polymer products according to the invention can be used with particularly good results for cements. The term "cement" denotes all chemical combinations of (lime + silicon oxide + alumina) or of (lime + magnesium oxide + silicon oxide + aluminum oxide + iron oxide) which are usually referred to as hydraulic cements. The preferred cements are the cements of the Portland type in which the clinker increases to at least 65 percent by weight and the possible additions, which amount to a maximum of 35 percent by weight, can be fly ash from heating plants, pouzzo slag, blast furnace slag or mixtures of these products. The aforementioned Portland cements usually contain calcium sulphate which is introduced in the form of gypsum or anhydride.

Other types of cement that can be used include slag cements which consist of 50 to 80 percent by weight slag and 50 to 20 percent by weight Portland clinker, such as e.g. mixed metallurgical cement, blast furnace cement, or slag-cement clinker. You can also use special cements such as masonry cement and other types of masonry.

One of the applications for the polymer products to be described consists of mixing in the content of additives in the production mixtures of mortars and concrete intended to adhere to building materials.

For the production of mortars and concrete, the type and amount of aggregate material such as sand, gravel, pebbles can vary within wide limits.

The polymer products according to the invention can be introduced into the binder and the aggregate material before the finished mixture or preferably into the mixing water before this is added. The polymer product can also be introduced into the mortar or the fresh concrete immediately before its use. It is noted that the term "mixing water" includes water introduced by the aqueous product.

The mortar or the fresh concrete with the addition of the polymer product according to the invention is then fixed on the building material which is treated using various working methods known to the person skilled in the art.

One can e.g. apply the mortar or fresh concrete directly to the building material, as the latter may be moistened with water in advance.

A preferred and often used way of working consists in beforehand coating the building material with a thin film of a booklet primer. Adhesion primer is understood to mean a mixture that is made up of approximately 20 to 98 percent by weight of the mortar or concrete that is to be brought to adhesion and approximately 80 to 2 percent by weight of water. The term "thin film" means that the adhesive primer has a thickness that is at most equal to the largest parts of the aggregate material in the mortar or concrete. The bonding primer that serves to provide adhesion to the substrate is determined so that satisfactory bonding conditions are achieved. Then, approximately 15 to 45 minutes after the substrate is covered with the adhesive primer, the remaining mortar or concrete is applied.

A working method which is particularly suitable in that it allows the polymer products according to the invention to be utilized to the maximum extent consists of applying the building material in advance using a thin film of enriched binder primer. The term "enriched" denotes that the primer includes, among other things, a supplementary quantity of the additive polymer product itself. A further use of the polymer products according to the invention is indicated here by introducing a certain amount of the said product into a binding primer beyond the part of the mortar or fresh concrete that is brought to binding with the water used for its production .

The mortar or the fresh concrete to be mentioned contains a certain amount of additive polymer product, but one does not go outside the scope of the invention if one starts from a mortar or fresh concrete that does not contain the aforementioned mixture if one only uses the product according to the invention as an additive in the adhesive primer used to attach the mortar or the fresh concrete that does not contain the polymer product.

The polymer products that are well suited on the one hand for producing mortars and fresh concrete for bonding to building materials and on the other hand for the production of bonding primers are those which, on a weight basis, contain:

- 50 to 95 and preferably 70 to 95% of mixture (a),

50 to 5% and preferably 30 to 5% of the aqueous solution (b) where the weight content of the dry product(s) is between 30 and 50%.

Among the products that can be used most advantageously are the polymer products in which:

- the mixture (a) is a binary mixture with formula: latex A

+ latex B (and preferably with formula: latex Al + latex Bl) or a ternary mixture with formula:' latex A + latex B + latex C (and preferred with formula: latex Al + latex Bl + latex Cl) in which the ratio latex A /latex B (or latex Al/latex Bl) is between 3 and 50, and

- the aqueous solution (b) contains:

- a water demand reducing agent selected from among the water-soluble salts of the condensation products with a molecular weight between 1,500 and 10,000 obtained by condensation with formaldehyde of sulfonation products of aromatic, monocyclic or polycyclic condensed hydrocarbons containing 1 to 12 benzene nuclei, and preferably selected from the salts of sodium , potassium, calcium, barium, ammonium, tetramethylammonium, or the condensation product of molecular weight between 1,500 and 10,000 obtained by condensing 3-naphthalene sulfonic acid with formaldehyde, and optionally a soluble salt of a strong oxygen-containing one acid selected from the alkali metal and ammonium derivative salts of nitric acid, sulfuric acid, sulfuric acid, phosphoric acid, brthophosphoric acid, pyrophosphoric acid, chromic acid, cyanoacetic acid, cyanopropionic acid, maleic acid, oxalic acid, orthonitribbenzoic acid and preferably from sodium sulfate, sodium nitrate and sodium oxalate

In the following, the term "used amount" of the polymer product according to the invention means the amount that is necessary to produce the snow mortar or the fresh concrete that is to be set (part of the said mortar or concrete can in the selected in some cases serve for the production of a booklet primer) + possibly the supplementary quantity for introduction into the booklet primer when you choose to work with an enriched booklet primer.

The doses used of the polymer product according to the invention, expressed as a percentage by weight in relation to the weight of the hydraulic binder, can vary within wide limits. For economic reasons, it is desirable that the doses used

of synthetic organic additives used in accordance with the invention does not exceed 20 percent by weight in relation to the weight of hydraulic: binder. This desire is fulfilled in particular by the fact that it has been found that the polymer products according to the invention can be successfully used in amounts of 1 to 2 percent by weight in relation to the hydraulic binder.

When using an enriched booklet primer technique, the amount of additive mixture that serves to enrich the booklet primer is more than 30 percent by weight of the applied dose of the additive polymer product.

When the mortar or the fresh concrete to be attached to the substrate does not contain an additive polymer product and when you want to use an adhesive primer containing the polymer product according to the invention, the amount of the latter used for the production of the adhesive primer represents no more than 30% by weight of the hydraulic binder present in the booklet primer.

The polymer product according to the present invention can also be used successfully for the production of thin mortars of hydraulic binders intended for the production of industrial coatings based on open bituminous coatings.

The industrial coatings based on bitumen-containing aggregates comprise two main components:

A bituminous mixture, prepared in a hot state,

of well-calibrated aggregates with a grain size between a few micrometers and 20 mm with a bitumen with a penetrability index between 60 and 100. The bituminous product that comes from this mixture produces the special

property that, after optimal compensation, it contains 10

40 percent cavities in the form of air cells with variable

shapes and dimensions. This special property is the origin of the term "open bituminous coatings". The usual thickness of this layer is about 20 to 50 mm.

A thin mortar of hydraulic binder, usually a cement thin mortar, which is deposited in a manner known per se on this bituminous layer to maximally fill the voids in the cellular structure to impart to the industrial coating a surface character or "finished" quality and also improved mechanical properties.

In order for the tyhn mortar to fulfill its role correctly, it is fluid and offers particularly good resistance to abrasion and good adhesion to the bituminous substrate. The polymer product according to the invention allows online production of thin mortar for industrial coatings on the basis of open bitumen-containing aggregates that fully correspond to the users' requirements.

It is noted that the polymer products are well suited for this type of application when they contain by weight:

10 to 50% and preferably 10 to 40% of the mixture (a),

- 90 to 50% and preferably 90 to 60% of aqueous solution (b) where the weight content of dry or dry products is between 10 and 30%.

Among these products, those that are most suitable are those in which the mixture (a) and the aqueous solution (b) correspond to the previously preferred definitions within the area of the production of mortars and fresh concrete intended to adhere to building materials but then with the condition of the mixture (a) that the ratio latex A/ latex B> (or latex Al/ latex Bl) is between 0.5 and 10.

Aggregates are used for the production of thin mortar

small dimensions, especially sand with a grain size between 0.01 and 0.3 mm.

The polymer product can be introduced into the binder and aggregates before mixing or can just as well be introduced into the mixing water immediately before its use. Preferably, the polymer product is introduced into the thin mortar after homogenization of the mixture consisting of water, hydraulic binder and the aggregates.

The application of the thin mortar takes place with the help of a blade

knife and the penetration into the layer of bituminous aggregate is carried out again with a device which - by those skilled in the art - is called a "vibrator roller". A suitable device is e.g. a vibratory roller with an axle with a weight of 500 kg and which e.g. marketed by the companies Boomag or Richier. A final treatment allows the removal of excess thin mortar and leaves the substrate or ground with a nice looking surface.

The amounts of the additive polymer product according to the invention that is used, expressed as a percentage by weight in relation to the hydraulic binder used for the preparation of the thin mortar, can vary within wide limits and it has been found that the polymer product according to the invention can be used successfully in amounts of 1 to 10 percent by weight in relation to the hydraulic binder.

One does not go outside the scope of the invention when the thin mortar containing the polymer product is used, after having served to consolidate the bitumen-containing aggregate, as an adhesive substrate between a coating of mortar or concrete and the bitumen-containing layer on which the said layer is deposited.

The following examples illustrate the invention and show how it is practiced. Examples 1 to 6 deal with products used for the production of mortars of Portland cement intended to adhere to building materials.

Example 7 treats a product used for the production of a thin mortar of Portland cement intended to serve for the production of an industrial covering based on open bituminous aggregates.

Example 1-3

l)___Def inis j_on_of_mortars

For each of these examples, the mortar has the following composition:

water:

for the production of control mortars (i.e. without polymer product): 202.5- g (E/C= 0.45) - for the production of mortars containing polymer product according to the invention, the water/cement weight ratio (E/C) is adjusted so that the workability of the control mortar is preserved. This setting is implemented by reducing the amount of mixing water.

The production of the mortar is carried out in accordance with standard NF.P. 15403. Cement and sand are mixed dry in the specified amounts and then the mixture cement + sand is added with the mixture (prepared in advance) of the additive polymer product according to the invention and water. 2) 3§£iSisi2D_§y_9i§2222}f ££t§_t§§£§£:

Flow test or measurement of the workability of the mortar:

This property is measured 10 minutes after mixing by expanding the mortar which has been previously cast into a truncated cone with a base diameter of 8 cm, an upper diameter of 7 cm and a height of 4 cm. The mortar is placed on a shaking table. The mortar is loosened manually in a manner known per se and after release from the mold the mortar is subjected to a series of 15 impacts with one impact per second. The shock is produced by a drop hammer from a height of 15 mm. The expansion is expressed in cm and corresponds to the average diameter of the cake obtained after different shocks.

Measurement of the resistance to compression (Rc) and to bending

(Rf) :

These are carried out according to standard NF.P. 15451. The resistances are determined on test pieces with dimensions 4 x 4 x 16 cm which, until the date of the test, have been stored under three types of conditions represented by the symbols: EH, SEC,

and H20 of which EH means that the samples have been stored at 20°C in a cabinet with 100% relative humidity, further SEC means that the samples have been stored at 20°C in a cabinet

with 50% relative humidity and finally E^O means that the test pieces are stored in water at 20°C.

For the bending test, the test piece is placed on 2 rollers with a diameter of 10 mm at a distance of 106.7 mm, with a third roller of the same diameter located at the same distance from the other two rollers transmitting a load that can be increased by 5 deca N/sec. The resistance to bending corresponding to the fracture of the test piece is expressed in bar.

The compression test is carried out with two test pieces from the bending test. The compression is carried out using two steel plates with at least 10 mm thickness, 40 mm width and 40 mm length. The load is increased until failure at a rate such that the increase amounts to 15 bar/sec. The result is expressed in bars.

The figures obtained are the average result of three test pieces subjected to bending and six measurements of compression.

- r- Measurement of adhesion:

This is measured using the so-called adhesion test, normalized by D.T.U. No. 26.1 (D.T.U: document Technique Unifié, published by the Center Scientifique et Technique du Batiment, Paris). The measurement of the adhesion is carried out using a pull-off dynamometer constructed by Société Sattec, division of C.E.B.T.P. (C.E.B.T.P.: Center d'Etudes du Batiment et des Travaux Publics, Paris),.

Each test piece is subjected to -measurement of adhesion and prepared by depositing the mortar, prepared as stated earlier by starting from 450 g of cement, on a support (French "comblancfiien"). with dimensions 30. x 30 cm (surface: 9.00 cm 2). It is noted that in all cases the support is covered approximately 30 minutes before the deposition of the mortar with a film of thin mortar comprising: in the case of the control sample: 150 g of mortar (without additive for deposition and 18 g of water

In the case of experiments according to the invention:

150 g mortar (additive added) for setting,

18 g of water and a supplementary amount of the additive itself.

The test piece is prepared and stored at 20°C in a cabinet with 50% relative humidity.

On the surface of the test piece, 9 circular sleeves with a diameter of 5 cm (surface area: 20 cm 2 ) are placed which go through the entire thickness of the mortar (approximately 1 cm) to the substrate, distributed so that there is the same distance between them. The test consists in detaching the isolated cylindrical parts by subjecting them to a perpendicular. tensile force against the plane of the specimen.

For this, a metal side is glued to each isolated part with the same diameter and one cm thickness and this disc is subjected to the pulling force against its axis with the apparatus constructed by Societe Sattec. Standard NF.P. 30062 defines the method of detachment using the pulling force that is exerted.

One obtains the value for the adhesion of the mortar to the substrate if the fracture takes place in their contact plane.

But it may turn out that the fracture takes place in a plane either in the mortar or in the substrate or just as easily in part with the contact plane and in the mortar or in the substrate.

In the first two cases, the obtained value is the adhesion of the mortar to the substrate and in the third case, the obtained value is not exact, but it indicates that the tensile strength in the mortar or substrate approximately corresponds to the adhesion and gives an average value.

In all these cases, however, the value obtained represents a minimum value for the adhesion.

The glue used for gluing the metal discs is epoxy glue, e.g. "araldite" which is suitable in all cases of mortars and where the curing time at a temperature of 20°C is 24 hours.

The gluing of the metal discs is carried out after the discharge

of 21 days. The value for adhesion of the mortar for adhesion of the mortar to the substrate is determined in a first series of measurements, after storage of the test piece for 28 days at 20°C in 50% relative humidity (SEC) and in a second series of measurements after storage of the test piece 2 8 days at 20°C in 50% relative humidity + 7 days in water at 20°C (H2O). The adhesion value is the arithmetic mean of the adhesion values determined for each cylinder of mortar isolated in the test piece.

For a mortar to be considered an adhesive mortar

no result must be lower than 3 bar at 28 days (SEC) or at 28 days + 7 days in water (H20).

Measurement of wasting and starvation:

These are defined using standard NF.P; 15433. Mon

measures as a function of time the variations in the length of test pieces of mortar with dimensions 4 x 4 x 16 cm which, after removal from the mold, have been stored for 90 days either in air at 50% relative humidity and 20°C for the shrinkage test or in water at 20° C for the swelling test. The variations are expressed as micrometres/metres.

Measurement of occluded air (entrained air):

At the end of 2 4 hours, the weight of the test pieces is measured

with dimensions 4 x 4 x 16 cm produced with control

mortar and with mortar added to the polymer product according to the invention. The amount of occluded air, expressed as a percentage, is given by the formula:

1Q0x weight of control specimen - Weight of test specimen weight of the control test piece 3) 3§finis2on_av_de_tilsetnin is used:

3.1) When carrying out these examples, the following are used:

A mixture of latex a) with formula: latex Al + latex Bl in which: latex Al consists of an aqueous dispersion with 50 percent by weight of a copolymer styrene/N-butyl acrylate, the glass transition temperature is 16°C and the particle diameter approximately 0.1 micrometer. The pH of the dispersion is approximately 5. The viscosity is measured using a Brookfiled RVT viscometer at 23°C and 50 rpm. is 500 cPo (latex A2); - latex Bl consists of an aqueous dispersion with 50% by weight of a copolymer styrene/butadiene-1,3. The lowest temperature for film formation is lower than 0°C and the diameter of the particles approximately 0.16 micrometres. The pH of the dispersion is approximately 7. The viscosity measured using a Brobkfleld RVT viscometer at 23°C at 50 revolutions/min. is 80 cPo (latex B2); an aqueous solution (b)_ containing 40% by weight sodium salt of the condensation product g-naphthalenesulfonic acid/formaldehyde with an average molecular weight of 4980. The production of this aqueous solution of sodium polymethylene-naphthalenesulfonate (abbreviated: solution of PNS-Na) is carried out in the following way: 640 g (6.5 mol) of concentrated sulfuric acid (d = 1.84) are introduced into a 3 liter flask equipped with a mechanical stirrer and heating system, which is brought to a temperature of 160°C. Stirring is continued and 640 g (5 mol) of purified naphthalene are added slowly, keeping the temperature at the mentioned value.

After the addition of naphthalene, the reaction mixture is stirred at 160°C until all the naphthalene has reacted. Time required is approximately 4 hours.

The sulfonation mixture is then cooled to 100°C and diluted with 282 g of water. The temperature in the mixture is brought to 80°C and 76.8 g of an aqueous solution of formaldehyde with 40% by weight HCHO is added. The reaction mixture is then stirred at 80°C for one hour.

At the end of this time, 76.8 g of the aqueous solution of formaldehyde are reintroduced into the reaction mixture and the stirring is continued at 80°C for one hour. This type of operation is repeated two more times.

After all the formaldehyde solution (307.2 g) has been added, the temperature in the reaction mixture is gradually increased to 95 - 100°C over a period of approximately 1 hour. After reaching this temperature, the reaction mixture is kept under stirring for a further 18 hours.

At the end of this time, it is cooled to normal temperature (25°C) and by means of potendiometic measurement, sulfuric acid (corresponding to 1.5 mol of sulfuric acid) and sulphonic acid (corresponding to 5 mol of sulphonic acid) are added. The reaction mixture is then accurately neutralized with an aqueous mixture containing 111.15 g of CaOH 2 and 200 g of NaOH. The lime neutralizes the sulfuric acid and gives a precipitate of hydrated calcium sulphate which is separated by filtration. After filtering the solution, this contains the desired sodium polymethylene naphthalene sulphonate. The filtrate is subjected to evaporation to isolate an aqueous solution containing 40% by weight of pure sodium polymethylene naphthalene sulfonate.

3.2) v Mixtures:

The following mixtures are produced:

The percentages are given as a percentage by weight.

4) Mørtelp_robber_02_results:

In each of the examples 1-3, the tests are carried out with a mortar prepared from 450 g of Portland cement of artificial type CPA-400 Guerville, using the additive polymer product according to the invention in an amount of 5 percent by weight in relation to cement (22.5 g).

For the adhesion test, as previously indicated, an enriched binder primer containing a supplementary amount of 6 g of the additive polymer product is used. To carry out the test, the polymer product according to the invention is then used in a total amount of 6.3% by weight in relation to the cement. The amount of additive polymer product (6 g) that serves to enrich the adhesive primer represents 21 percent by weight of the amount used (28.5 g) of the additive polymer product.

For comparison, a test is carried out with mortar without an additive polymer product (control mortar: test A).

The results obtained are reproduced in the following table:

Examples 4 to 6

When carrying out these examples, the following is used:

A mixture of latex 4a) with formula:

latex Al + latex Bl + latex Cl in which:

latex A1 has the meaning as latex A2 used in examples 1-3

latex Bl has the meaning of latex B2 used in examples 1-3;

latex Cl consists of an aqueous dispersion with 50% by weight of a homopolymer of vinyl acetate. The minimum film formation temperature is 2°C and the particle diameter approximately 1 to 3 micrometers. The pH of the dispersion is approximately 4.5 and the viscosity measured using a Brookfield RVT viscometer at 23°C and 50 rpm. is 1500 cPo (latex C2).

The aqueous solution (b) is ONS-Na used in examples 1-3.

1) Compositions:

The following mixtures are produced:

2) Trials with mortars and results:

One works with the same conditions as in examples 1-3. The control mortar is the same as in the previous experiment A.

The results are collected in the following table.

Example 7

1) DefinisiQn_a.Y_tYnnmortar:

It offers the following composition:

Normalized sand Fl (grain size between 0.06 and

0.3 mm): 50 parts by weight

Portland cement type CPA-400 HTS marketed by Societe Lafarge: 50 parts by weight

- water

for the production of control thin mortar (without addition): 30 parts by weight

for the production of thin mortar with addition where the amount of water is set so that the workability of the control thin mortar is maintained. This setting is implemented by reducing the amount of mixing water.

The production of the thin mortar is carried out using

of a mixing pump sold under the designation "Putzmeister P 13". In this apparatus, water is added in the order mentioned, first and then cement and sand. The additive polymer product is then added after homogenization of the aforementioned mixture. After production, the thin mortar is transported by means of a pump to the application site using the aforementioned device.

2) Definition of conducted tests:

- Measurement_of_the workability of the mortar;

This property of the cement mortar is measured using the so-called Marsh cone. Its dimensions are as follows: 1 liter total volume, discharge nozzle diameter 5 mm and length 50 mm. At 20°C, the cone is filled with fresh thin mortar and the time is measured in seconds required to completely empty the cone (with water, for example, a flow time of 32 sec. is required).

^l<i>i22_§Y_§^E§§i2Ssthe_resistance_for_the_thinning_mortar:

This measurement is carried out using the so-called Schokke device. The test consists of subjecting a parallel-epipedic test piece to the thin mortar, after 7 days of ageing, with a combined effect of longitudinal brushing and rotation in the dry state. The brush consists of stainless steel filaments. The dimensions of the test piece are 15 x 10 x 1 cm. The weight loss of the test piece is measured after 30 seconds, 1 minute, 3 minutes and 10 minutes.

A high loss means poor resistance, and a greater loss means better resistance to abrasion. The weight loss is expressed as percentages.

Målin^_av_inntr^n^n^n^_i_in^u^ :

The industrial substrate tested here is produced by applying cement-thinning mortar, as indicated earlier in the description, on a bituminous gravel prepared by Societe Chimique de la Route, with the following characteristics: it is produced by hot mixing of aggregates with grain size between a few micrometers and 14 mm and bitumen with penetration 60/70

it has percentage voids of about 30%'.,

- when deposited, it has an average thickness of 35 mm.

The measurement of the resistance to penetration is carried out after

7 days using a device developed by Societe Chimique de la Route and Sacer consisting of a metal disc with a 5 cm 2 surface that is loaded with variable weights from a few kg to 350 kg and placed on the industrial substrate or cover. The resistance is expressed in bar and is calculated directly by starting from the value of the weights which, during three hours at 25°C, cause a penetration from rrnm to a maximum in the industrial substrate or cover.

<3>) 2§£i2i§222J5Y_£ii§§£Din25rE2lYS§£2£2^!i3s£et:

One uses:

a mixture of latex (a) with formula:

latex Al + latex Bl in which:

latex A1 has the meaning of latex A2 used in examples 1-3

latex Bl has the meaning of latex B2 used in examples 1-3

an aqueous solution (b) containing 20% by weight of a mixture of the sodium salt of the condensation product of 3-naphthalenesulfonic acid/formaldehyde with an average molecular weight of 4980 (82%) with sodium sulfate (18%).

The production of this aqueous solution (b) is repeated in the following way: for the sulfonation step for naphthalene and the condensation with formaldehyde, the procedure described earlier in examples 1-3 is repeated

however, one proceeds at the end of the reaction with an exact neutralization of the mixture using only UaOH

The neutralization mixture is then subjected to evaporation so that an aqueous solution containing 40% by weight of a mixture of sodium polymethylene naphthalene sulphonate and Na^O^ is isolated. The concentrate is then diluted with an equal volume of water to obtain the aqueous solution (b) used in this example.

The following mixture is prepared:

Mixture (a):

Latex A2: 9.5% by weight

Latex B2: 9.5% by weight

Aqueous solution (b): 81% by weight

4) Test with thin mortar bg results:

This test is carried out with a thin mortar prepared as indicated previously under section 1) into which 2 parts by weight of the additive polymer product as previously indicated (4 percent by weight in relation to cement) and 25.5 parts by weight of water are introduced.

For comparison, a thin mortar is formed without the additive polymer product (control experiment A')

Claims (13)

1. Polymer products particularly useful as additives for mixtures based on hydraulic binders, characterized in that they contain the following main components: (a)_ a mixture of at least 2 aqueous dispersions of vinyl polymers, and (b) an aqueous solution containing either a water demand reducing agent or a mixture of a water demand reducing agent and a water-soluble salt derived from monovalent or polyvalent oxygen-containing inorganic acids or carboxylic acids, where at least one of the acid functions has an ionization constant pKa in water at 25°C lower than 2.5. 2) Polymer product as specified in claim 1, characterized in that the latexes used for the preparation of the mixture (al are selected from the group exercised by: - latex (designated latex A) which results from the copolymerization of a monomer of the aromatic hydrocarbon type containing 2 to 14 carbon atoms and one or two bonds of ethylene character with a monomer of the acrylic acid or methacrylic acid type which can be an acid, an ester of this acid with aliphatic or cycloaliphatic saturated alcohols but up to 8 carbon atoms, or a nitrile, an amide, or an anhydride derived from this acid latex (designated latex B); which results from the copolymerization of a monomer of the aromatic hydrocarbon type containing 2 to 14 carbon atoms and one or two bonds of ethylene character with a monomer of the aliphatic di-ethylene-unsaturated hydrocarbon type containing 2 to 14 carbon atoms latex (designated latex C) which results from the homopolymerisation of a monomer selected from the group of vinyl esters of saturated aliphatic acids or aromatic acids with up to 10 carbon atoms, latex (designated latex D) resulting from the copolymerization of at least two vinyl esters selected from those specified for latex C. 3. Polymer product as stated in claim 1 or 2, characterized in that the mixture (a) of latex is a binary mixture with the formula latex A + latex B in which latex A and B have the meanings given in claim 2. 4. Polymer product as stated in claim 1 or 2, characterized in that the mixture (a) of latex is a ternary mixture with the formula latex A + latex B + latex C in which latex A, B and C have the meanings given in claim 2 . 5. Polymer products as specified in claim 3, characterized in that the amount of latex A in the mixture latex A + latex B expressed as a weight ratio latex A/latex B is between 0.5 and 50. 6. Polymer products as stated in claim 4, character is shown by the fact that the weight ratio latex A/latex B has the value given in claim 5 and that the amount of latex C amounts to 30% of the weight of the mixture latex A + latex B + latex C. 7. Polymer product as stated in claim 1 6, characterized in that the water demand reducing agent consists of water-soluble salts of condensation products with molecular weights between 1,500 and 10,000 obtained by condensation with formaldehyde of the sulfonation products of aromatic monocyclic or polycyclic condensed hydrocarbons containing 1 to 12 benzene nuclei, or by the mixture of the aforementioned salts with water-soluble salts derived from sulfonation products of polycyclic condensed aromatic hydrocarbons containing 2 to 12 benzene nuclei. 8. Polymer product as stated in claims 1-7, characterized in that the layer of inorganic or strong carboxylic acid which can be introduced into the aqueous solution (b) next to the water demand reducing agent is selected from the group consisting of alkali metal salts and ammonium derivative salts of nitric acid, sulfuric acid, sulfuric acid, phosphoric acid, orthophosphoric acid, pyrophosphoric acid, chromic acid, cyanoacetic acid, cyanopropionic acid, maleic acid, oxalic acid and orthonitrobenzoic acid. 9. Polymer product as stated in claims 1-8, characterized in that it contains 10-95% by weight of the mixture (a) of at least two latexes, and 90-5% by weight of aqueous solution (b). 10} Polymer product as stated in claims 1-9, characterized in that the latex used contains 30 to 60 percent by weight of dry polymer. 11) Polymer product as specified in claims 1 - 10, characterized in that the aqueous solution (b) contains 10 to 50 percent dry or dry products. 12) Polymer product as specified in claim 11, characterized in that the weight ratio of soluble salt of inorganic acid or strong carboxylic acid in the mixture of dry products (water demand reducing agent and salt of organic acid or strong carboxylic acid) represents no more than 25%. 13) Use of the polymer products as stated in claims 1-12, as additives for mixing ..in mixtures for the production of mortars and concrete based on hydraulic binders intended for application to building materials or as additives for mixing in adhesive primers or thin mortars for fixing mortars and fresh concrete with hydraulic binders on the building materials.