WO2010146252A2

WO2010146252A2 - Composition for waterproofing and improving the beading effect of construction materials

Info

Publication number: WO2010146252A2
Application number: PCT/FR2010/000437
Authority: WO
Inventors: Christian Maliverney; Frédéric MARCHAL
Original assignee: Bluestar Silicones France
Priority date: 2009-06-19
Filing date: 2010-06-15
Publication date: 2010-12-23
Also published as: WO2010146252A3

Abstract

The invention relates to a waterproofing liquid silicon composition intended for impregnating porous construction materials, for example mineral or (ligno)cellulosic materials.

Description

COMPOSITION FOR HYDROFUGGING AND ENHANCING THE PERLING EFFECT OF CONSTRUCTION MATERIALS

The field of the invention is that of hydrofugation of porous construction materials (especially mineral or [ligno] cellulosic), therefore sensitive to moisture. In general, water repellency is performed on building material elements when assembled to form parts of buildings.

Water repellency is a surface treatment intended to limit the penetration of water, by application of a product that modifies the surface tension of the treated material. A water repellency treatment is required to:

- reduce the water intake by capillarity (reduction of the water absorption coefficient> 90%);

- has little effect on the water vapor permeability (variation of the permeability coefficient <20%), and

- does not change the appearance of the treated material (color, gloss, roughness)

Surface water repellents are colorless products which make it possible to waterproof the surface layer of the porous construction material, without substantially modifying its appearance or permeability to water vapor. For example, when the porous building material is concrete, it is desirable that the pores and capillaries of the concrete be coated inside, but not filled. There is no film formation on the surface.

This waterproofing is intended in particular to better protect the material against the penetration of water, usually from driving rain or rising water from the ground. It is well known to hydrofuge construction materials, either during their manufacture or after their installation, using water-repellent agents which, in the case of materials such as stones, plaster or brick, are more generally silicone-based compositions.

Water-repellency using the water-repellent agent previously dissolved or dispersed in a suitable solvent or liquid, aqueous or otherwise, may be effectively made on the surface, in which case the surface of the material is coated with whitewash or the water-repellent agent, or be made in depth and, in this case, the water-repellent agent is introduced into the mass, which is possible for example for bricks, wood, concrete, plaster or reconstituted stones .

In the case of natural stones or in situ materials forming for example existing walls, it is possible to carry out a surface treatment or to inject the water-repellent agent into the mass by forcing under pressure using a cannula introduced into a hole. injection properly practiced in the material; the water-repellent agent can also be infiltrated or penetrated by imbibition and diffusion by capillarity in the material.

Silicone liquid waterproofing compositions exist either in the form of solutions in organic solvents such as "white spirit" or heptane, or in the form of aqueous emulsions appeared more recently on the market. Conventionally, after the impregnation, the organic solvent phase or the aqueous phase of these compositions volatilises and the silicone active material remains in the mass and at the periphery of the porous construction material, so as to form a barrier against moisture.

In order for water repellency using a liquid silicone composition to be successful, it is important to:

- that the rheology of the latter allows penetration into the porous construction material over a thickness ranging from several millimeters to several centimeters,

that a reaction occurs between the porous building material and the active silicic acid waterproofing material,

and that, preferably, this active silicic material cross-links in the porous construction material, this crosslinking possibly being the reaction which will generate the creation of bonds between the porous construction material and the silicic water-repellent material.

However, one of the difficulties encountered in the formulation of liquid water-repellent composition is the search for a satisfactory beading effect. The beading effect is an important property for the application because it is directly perceived by the end user. It characterizes the visual aspect of the support once for example that the latter has been wet by rain. The less water that stays on the surface, the better the beading effect.

The water-repellency treatments of interest in the context of the invention are those carried out using liquid silicone compositions, comprising polyorganosiloxane resins. The porous building materials considered can be for example stones based on calcium carbonate and / or silica and / or alumino-silicates, concretes, mortars, plasters, terra cotta (bricks, tiles, etc. .), wood or other similar building materials having a certain porosity or a surface condition for the implementation of a water repellent.

By wood, we mean the wood used especially in existing buildings, old or new, such as external and internal woodwork, beams, half-timberings, carpentry. Wood is, as we know, a porous material that strongly absorbs water. Thus, an object of the present invention is to develop a liquid silicone composition no longer having the disadvantages mentioned above.

To achieve this objective, the inventors have had the merit of highlighting, quite surprisingly and unexpectedly, that a water-repellent composition based on silicone resin and in carefully chosen contents of each of the constituents of a mixture of catalyst containing at least one metal alkoxide, a crosslinking agent preferably chosen from silicates and a specific guanidine makes it possible to obtain compositions which have, in addition to interesting water repellency properties, a remarkable beading effect.

In particular, the invention relates to the use of silicone liquid waterproofing compositions for impregnating porous materials of construction, for example mineral or (ligno) cellulosic.

The invention also relates to a process for the hydrophobicization of porous construction materials, preferably mineral or (ligno) cellulosic materials, using the aforementioned liquid silicone composition.

These objectives, among others, are achieved by the present invention which firstly relates to a liquid silicone composition comprising: a) at least one polyorganosiloxane resin A having, per molecule, on the one hand at least two different siloxyl units selected from those of types M, D, T, Q, one of the units being a unit T or a unit Q and, on the other hand, at least three hydrolyzable / condensable groups of types OH and / or OR ¹ where R ¹ is a linear alkyl radical or branched C ₁ to C ₆ ; b) at least one metal alkoxide B in which the metal M may optionally be partially bound to one or more ligands, in a content of> 0.5% by weight, preferably> 3.5% by weight and even more preferentially> to 7 % by weight relative to the polyorganosiloxane resin A, said metal alkoxide having the general formula:

M [(OCH ₂ CH ₂ ) _a -OR ² ] _n (I) in which:

M is a metal selected from the group consisting of: Ti, Zr, Ge, Mn and Al;

n = valence of M;

the substituents R ² , which are identical or different, each represent a linear or branched C ₁ to C ₁₂ alkyl radical; - a represents zero, 1 or 2; with the conditions according to which, when the symbol a represents zero, the alkyl radical R ² has from 2 to 12 carbon atoms, and when the symbol a represents 1 or 2, the alkyl radical R ² has from 1 to 4 carbon atoms; carbon; c) at least one crosslinking agent C, in a content of> 0.5% by weight, preferably> 2% by weight and even more preferably> to 5% by weight relative to the polyorganosiloxane resin A, said crosslinking agent C having the formula

Si [(OCH ₂ CH ₂ ) _a -OR] ₄ (H) in which: the substituents R, which are identical or different, each represent a linear or branched C 1 to C ₁₂ alkyl radical, and

- a represents zero, 1 or 2; and d) at least one unsilylated organic compound D, in a content of> 0.1% by weight, preferably> 1% by weight and even more preferably> to 1.5% by weight relative to the polyorganosiloxane resin A and responding to the general formula (Ia):

R ¹ - NH R ²

R ¹

(Ia) in which:

the radicals R ¹ , which may be identical or different, represent, independently of each other, a linear or branched monovalent alkyl group, a cycloalkyl group or a (cycloalkyl) alkyl group, the ring being substituted or unsubstituted and which may comprise at least one minus one heteroatom or one fluoroalkyl group,

the radical R ² represents a hydrogen atom, a linear or branched monovalent alkyl group, a cycloalkyl group, a substituted or unsubstituted ring-substituted alkyl group and may comprise at least one heteroatom, an aromatic group or an arylalkyl group, a fluoroalkyl group, an alkylamine or alkylguanidine group, and

the radical R ³ represents a linear or branched monovalent alkyl group, a cycloalkyl group, a substituted or unsubstituted ring-substituted alkyl group and may comprise at least one heteroatom, an arylalkyl, fluoroalkyl, alkylamine or alkylguanidine group,

when the radical R ² is not a hydrogen atom, the radicals R ² and R ³ may be linked to form a 3-, 4-, 5-, 6- or 7-membered aliphatic ring optionally substituted with one or more substituents, and with the additional proviso that the radicals R ¹ , R ² and R ³ do not comprise a silicon atom,

According to a preferred embodiment, the unsilylated organic compound D is an unsilylated organic compound selected from the group consisting of the following compounds (D1) to (D6):

(D5) (D6)

According to another embodiment, the composition according to the invention also contains an organic solvent that can be used for the waterproofing of building materials. As an example of a solvent, mention may be made, without limitation, of organic solvents such as "white spirit" or heptane.

The constituents A that may be used, separately or as a mixture, are conventional silicone resins, among which mention may be made of organosilicon resins prepared by cohydrolysis and cocondensation of chlorosilanes chosen from the group consisting of those of formulas (R ³ ) ₃ SiCI, (R ³ J ₂ Si (CI) ₂ , R ³ Si (Cl) ₃ and Si (Cl) _4. These resins are well-known and commercially available branched organopolysiloxane oligomers or polymers having at least two siloxyl units in their structure. different ones chosen from those of formula (R ³ ) ₃ SiO _0.5 (M unit), (R ³ J ₂ SiO (D unit), R ³ SiO _{1 5} (T unit) and SiO ₂ (Q unit) ₁ at least one of these units being a T or Q unit R ³ radicals are distributed such that the resins comprise approximately 0.8 to 1, 8 R ³ radicals per silicon atom. in addition, these resins are not completely condensed and they still possess about 0.001 to 1, 5 OH groups and / or OR ¹ alkoxyl per silicon atom.

The radicals R ³ are identical or different and are chosen from linear or branched C1-C6 alkyl radicals, C2-C4 alkenyl radicals, phenyl, 3,3,3-trifluoropropyl radicals. Mention may be made, for example, as R ³ alkyl radicals, the methyl, ethyl, isopropyl, tert-butyl and n-hexyl radicals.

Examples of oligomers or branched organopolysiloxane polymers that may be mentioned are MQ resins, MDQ resins, DT resins and MDT resins, OH and / or OR ^{1 groups that} may be carried by the M, D and / or T units. the content by weight of OH and / or oR ¹ groups being between 0.2 and 10% by weight.

With regard to the constituents B, examples of the symbols R ² in the organic derivatives of the metal M of formula (I) include the following radicals: methyl, ethyl, propyl, isopropyl, butyl, isobutyl and hexyl , 2-ethylhexyl, octyl, decyl and dodecyl.

As concrete examples of constituents B which are preferred, mention may be made of: alkyl titanates such as ethyl titanate, propyl titanate, isopropyl titanate, butyl titanate, 2-ethyl hexyl titanate , octyl titanate, decyl titanate, dodecyl titanate, β-methoxyethyl titanate, β-ethoxyethyl titanate, β-propoxyethyl titanate, titanate of formula Ti [(OCH ₂ CH ₂ ) ₂ -OCH ₃ ] ₄ ; alkyl zirconates such as propyl zirconate, butyl zirconate; and mixtures of these products, they can also consist of a metal alkoxide where the metal M can be partially connected to one or more ligands such as for example those derived in particular from β-diketones, β-keto esters and malonic esters (for example acetylacetone) or triethanolamine.

As concrete examples of constituents C which are preferred, mention may be made of: alkyl silicates such as methyl silicate, ethyl silicate, isopropyl silicate, n-propyl silicate. According to a preferred embodiment, the crosslinking agent C is a silicate of formula Si (OR) ₄ in which the substituents R, which are identical or different, each represent a linear or branched C ₁ -C 12 alkyl radical.

According to another preferred embodiment metal alkoxide B is a titanate of formula Ti (OR ') ₄ in which the R' substituents, which are identical or different, each represent a linear or branched C ₂ -C ₁₂ alkyl radical.

According to a particularly advantageous embodiment, the crosslinking agent is a silicate of formula Si (OR) ₄ in which the substituents R, which are identical or different, each represent a linear or branched C ₂ to C ₁₂ alkyl radical and the metal alkoxide is a titanate of formula Ti (OR ¹⁾ ₄ in which the substituents R ', which are identical or different, each represent a linear or branched C ₁ -C 12 alkyl radical.

The invention also relates to a process for hydrofugging and improving the beading effect of porous building materials in which a liquid silicone composition according to the invention and as defined above is applied to the porous construction material.

According to a preferred embodiment of the method according to the invention the porous construction material is selected from the group consisting of: a stone, a concrete, a mortar, a brick, a tile and a wood.

The last subject of the invention concerns the use of a liquid silicone composition according to the invention and as defined above for water-repelling and improving the beading effect of porous building materials.

Other advantages and features of the present invention will appear on reading the following examples given by way of non-limiting illustration.

EXAMPLES

I) Preparation of catalysts according to the invention

a) 1-butyl-2.3-diisopropylanidine (AD:

A mixture of 33 g of N-butylamine (0.45 mol) and 19 g of diisopropylcarbodiimide (0.15 mol) is refluxed for 3 hours. The GC analysis then shows a conversion greater than 99.5

% of diisopropylcarbodiimide. The colorless final mixture is concentrated at 60 ^° C. under 20 mbar for 2 hours to give 29 g of a colorless and practically odorless liquid of low viscosity, corresponding to the expected guanidine (yield 96.7%).

¹ H NMR / CDCl ₃ (ppm): 0.93 (3H, t), 1.14 (12H, d), 1.37 (2H, sex), 1.52 (2H, quint), 3.01 (2H, t), 3.57 (2H, m).

b) 1-butyl-2,3-diisopropyl-1-methylquanidine (D3):

A mixture of 32.68 g of N-butyl-N-methylamine (0.375 mol) and 23.66 g of diisopropylcarbodiimide (0.1875 mol) is heated at reflux for 3 hours. The GC analysis then shows a conversion greater than 99.5% of the diisopropylcarbodiimide. The colorless final mixture is concentrated at 60 ^° C. under 5 mbar for 2 hours to give 40 g of a colorless and virtually odorless liquid of low viscosity, corresponding to the expected guanidine (100% yield). ¹ H NMR / CDCl ₃ (ppm): 0.88 (3H, t), 1.06 (12H, d), 1.26 (2H, sex), 1.46 (2H, quint), 2.67 (3H, s), 3.05 (2H, t), 3.35 (2H, m). c) 1-butyl-2,3-dicyclohexylquuanidine (D2) RN-CAS = 60006-40-8

A mixture of 15.69 g of N-butylamine (0.214 mol) and 22.13 g of dicyclohexylcarbodiimide (0.107 mol) is heated at reflux for 2 hours. The GC analysis then shows a conversion of more than 99.6% of the dicyclohexylcarbodiimide. The final colorless mixture is concentrated at 60 ^° C. under 1 mbar for 2 hours to give 29.7 g of a colorless and virtually odorless liquid of medium viscosity, corresponding to the expected guanidine (yield 99%).

d) 1-butyl-2,3-dicyclohexyl-1-methyl-uanidine (D4):

A mixture of 17.78 g of N-butyl-N-methylamine (0.204 mol) and 21.05 g of dicyclohexylcarbodiimide (0.102 mol) is heated at reflux for 3 hours. The GPC analysis then shows a conversion greater than 99.5% of the dicyclohexylcarbodiimide. The colorless final mixture is concentrated at 60 ^° C. under 1 mbar for 2 hours to give 29.9 g of a colorless and virtually odorless liquid of medium viscosity, corresponding to the expected guanidine (yield 99.7%). ¹ H NMR / CDCl ₃ (ppm): 0.89 (3H, t), 1-1.4 (10H, m), 1.47 (2H, quint), 1.5-2 (12H, several m), 2.67 (3H, m.p. H, s), 2.90 (1H, m), 2.97 (1H, m), 3.06 (2H, t). e) 1,2-Dihydrohexyl-3-piperidylaluanidine (D5) RN-CAS 60006-25-9:

A mixture of 11.69 g of piperidine (0.137 mol) and 14.16 g of dicyclohexylcarbodiimide

(0.0686 mol) is refluxed for 3 hours. The GPC analysis then shows a conversion greater than 99.7% of the dicyclohexylcarbodiimide. The final colorless mixture is concentrated at

6O ⁰ C under 1 mbar for 2 hours to give 19.9 g of a colorless liquid and practically odorless very viscous, corresponding to the expected guanidine (99.5% yield).

f) 1,2-Diocyclohexyl-3-pyrrolidyl-guanidine (D6) RN-CAS 60006-28-2:

A mixture of 19.2 g of pyrrolidine (0.27 mol) and 18.6 g of dicyclohexylcarbodiimide

(0.09 mol) is heated at reflux for 4h. The GC analysis then shows a conversion greater than

99.8% of dicyclohexylcarbodiimide. The colorless final mixture is concentrated at 60 ^° C. under 1 mbar for 1 h to give 24.9 g of a colorless and virtually odorless liquid of medium viscosity, corresponding to the expected guanidine (yield 99.6%).

W) Description of the test:

Formulas tested:

Various formulations are prepared with the following constituents: a) hydroxylated MDT silicone resin; b) n-butyl titanate (Bu) of formula Ti (OBu) ₄ : x parts by weight relative to the silicone resin; c) - ethyl silicate of formula Si (OEt) ₄ : y parts by weight relative to the silicone resin; d1) 1-butyl-2,3-dicyclohexyl-1-methylguanidine (D4) (invention): z1 parts by weight relative to the silicone resin, or

62) tetramethylguanidine (TMG, comparative): z2 parts by weight relative to the silicone resin.

The formulations tested are described in Table I (composition expressed in parts by mass, before dilution in xylene):

Board

Comp = comparative Inv. = Invention

Specimens cut in Tuffeau stone slabs, previously washed with water and then dried at 60 ^° C. and stabilized for at least 48 h under the temperature and humidity conditions of the laboratory, are treated by immersion in a solution of water-repellent prepared from the formulations 1 to 8 described above and diluted with 8% of active ingredient (in xylene): 2 immersions of 10 seconds each separated by a lag time of one minute. Then the beading effect is evaluated after 18h and 48h of crosslinking at room temperature: the plates are subjected to an artificial rain of 250ml of water and the amount of "retained" water is weighed, that is to say the amount of water that entered the test tube + the amount of water that remained on the surface. These amounts are normalized per unit area treated, and related to the amount of water retained by an untreated control sample. The beading effect is here expressed in%: 0% corresponds to the control (no beading effect) and 100% corresponds to a plate that does not retain water (optimal beading effect).

Results:

When the guanidines according to the invention (formulations 3 and 6) are added, the pearling effect is improved after 48 hours compared to the comparative tests which do not contain guanidines according to the invention (formulations 1 and 5).

The addition of tetramethylguanidine (formulations 2 and 4) under the same conditions of weight content clearly degrades the beading effect after 18h and 48h.

When the guanidines according to the invention (formulation 8) or tetramethylguanidine (formulation 7) are added to the composition without the presence of component b) (TiO (Bu) ₄ ), the results concerning the beading effect are no longer acceptable.

Claims

Silicone liquid composition comprising: a) at least one polyorganosiloxane resin A having, per molecule, on the one hand at least two different siloxyl units selected from those of types M, D, T, Q, one of the reasons being a pattern T or a Q unit and on the other hand at least three hydrolyzable / condensable groups of OH and / or OR ¹ types where R ¹ is a linear or branched C ₁ -C ₆ alkyl radical; b) at least one metal alkoxide B in which the metal M may optionally be partially bound to one or more ligands, in a content of> 0.5% by weight, preferably> 3.5% by weight and even more preferentially> to 7 % by weight relative to the polyorganosiloxane resin A, said metal alkoxide having the general formula:

M [(OCH ₂ CH ₂ ) _a -OR ² ] _n (I) in which: M is a metal selected from the group consisting of: Ti, Zr, Ge, Mn and Al;

n = valence of M;

the substituents R ² , which are identical or different, each represent a linear or branched C ₁ -C 12 alkyl radical;

- a represents zero, 1 or 2; - with the conditions under which, when the symbol a represents zero, the alkyl radical

R ² has from 2 to 12 carbon atoms, and when the symbol a represents 1 or 2, the alkyl radical R ² has from 1 to 4 carbon atoms; c) at least one crosslinking agent C, in a content of> 0.5% by weight, preferably> 2% by weight and even more preferably> to 5% by weight relative to the polyorganosiloxane resin A, said crosslinking agent C having the formula

If [(OCH ₂ CH ₂ ) _a -OR] ₄ (M) in which: the substituents R, which are identical or different, each represent a linear or branched C ₁ to C ₁₂ alkyl radical, and - a represents zero, 1 or 2; and d) at least one unsilylated organic compound D, in a content of> 0.1% by weight, preferably> 1% by weight and even more preferably> to 1.5% by weight relative to the polyorganosiloxane resin A and responding to the general formula (Ia):

(Ia) in which:

the radicals R ¹ , which are identical or different, represent, independently of one another, a linear or branched monovalent alkyl group, a cycloalkyl group, a group

(cycloalkyl) alkyl, the ring being substituted or not and may comprise at least one heteroatom or a fluoroalkyl group,

2 - Composition according to claim 1 wherein the unsilylated organic compound D is an unsilylated organic compound selected from the group consisting of the following compounds (D1) to (D6):

(D1) (D2)

(D5) (D6)

3 - Composition according to claim 1 characterized in that the silicone liquid composition further contains an organic solvent used for the waterproofing of building materials.

4 - Composition according to claim 1 characterized in that the crosslinking agent is a silicate of formula Si (OR) ₄ wherein the R substituents, same or different, each represent an alkyl radical, linear or branched Ci to C _12.

5 - Composition according to claim 1 characterized in that the metal alkoxide is a titanate of formula Ti (OR ') ₄ in which the substituents R', identical or different, each represent a linear or branched alkyl radical, C ₂ at Ci ₂ .

6 - Composition according to claim 1 characterized in that:

the metal alkoxide B is a titanate of formula Ti (OR ') ₄ in which the R' substituents, which are identical or different, each represent a linear or branched C ₂ to C ₁₂ alkyl radical, and the crosslinking agent is a silicate of formula Si (OR) ₄ in which the substituents R, which are identical or different, each represent a linear or branched C ₁ to C ₁₂ alkyl radical.

7 - Process for hydrofugging and improving the beading effect of porous building materials in which a liquid silicone composition as defined in any one of the preceding claims is applied to the porous building material. 8 - Process according to claim 7 wherein the porous building material is selected from the group consisting of: a stone, a concrete, a mortar, a brick, a tile and a wood.

9 - Use of a liquid silicone composition as defined in any one of claims 1 to 6 for water-repellent and improve the beading effect of porous building materials.