Sealant composition

Abstract

A one-part thermally porous surface condensation curable silicone composition comprising an organopolysiloxane polymer having at least two alkoxy groups per molecule and a titanate-based or zirconate-based catalyst wherein the thermally porous substrate is at a temperature of at least 40 DEG C. The porous substrates may be, for example, building materials including stone, marble, bricks, concrete, cement, and other cement substrates. The invention also relates to a method for applying a one-part thermally porous surface condensation-curable silicone composition to a thermally porous substrate at a temperature of at least 40 DEG C, and to the use of said one-part thermally porous surface condensation-curable silicone composition to treat a porous substrate at a temperature of at least 40 DEG C.

Description

[0001] The present invention relates to a one-part thermal porous surface condensation-curable silicone composition comprising an organopolysiloxane polymer having at least two alkoxy groups per molecule and a titanate-based or zirconate-based catalyst, wherein the thermal porous substrate is at a temperature of at least 40°C. The porous substrate may be, for example, a building material including stone, marble, brick, concrete, cement and other cementitious substrates. The present invention also relates to a method of applying the one-part thermal porous surface condensation-curable silicone composition to a thermal porous substrate at a temperature of at least 40°C, and the use of the one-part thermal porous surface condensation-curable silicone composition to treat a porous substrate at a temperature of at least 40°C.

[0002] Condensation-curable silicone compositions are well known. Typically, most such compositions are designed to be room temperature vulcanizable (RTV), where room temperature is about 20°C to 25°C. They typically comprise an -OH terminated diorganopolysiloxane polymer or an alkoxy terminated polydiorganosiloxane which may have an alkylene chain between the terminal and penultimate silicon atoms and one or more suitable crosslinking agents designed to react with the -OH and / or alkoxy groups and thereby crosslink the composition to form, for example, an elastomeric sealant product and one or more condensation cure catalysts. Additional ingredients such as reinforcing fillers, non-reinforcing fillers, tackifiers, diluents (e.g., plasticizers and / or extenders), chain extenders, flame retardants, solvent resistance additives, biocides, etc. are also typically incorporated into these compositions as needed and when desired.

[0003] They can be one-part compositions or multi-part compositions, such as two-part compositions. One-part condensation-curing (RTV) silicone compositions are typically used to produce skin or diffusion-cured silicone elastomers. It is well known to those skilled in the art that alkoxy titanium compounds and / or alkoxy zirconium compounds (i.e., alkyl titanates) are catalysts suitable for curing such one-component moisture-curable silicones. One-part condensation-curing silicone compositions are typically designed to contain no water / moisture in the composition as much as possible, i.e., they are typically stored in a substantially anhydrous form to prevent premature curing during storage prior to use. Skin or diffusion curing (e.g., moisture / condensation) occurs by forming a cured skin at the composition / air interface after the sealant / encapsulant is applied to the surface of the substrate. After the surface skin is produced, the curing rate depends on the diffusion of moisture from the interface of the sealant / encapsulant with air to the inside (or core) of the layer of the applied silicone composition, as well as the diffusion of condensation reaction byproducts / effluents from the inside (or core) of the material to the outside (or surface) and the rate at which the cured skin gradually thickens from the outside / surface to the inside / core over time. Such one-part condensation-curing silicone compositions are applied in layers that are typically thinner than 15 mm. It is known that such compositions applied in layers thicker than 15 mm can result in uncured material in the depth of the material because moisture diffuses very slowly into very deep parts. The primary source, if not the sole source, of moisture in these compositions is inorganic fillers, such as silica or calcium carbonate when present. The fillers may be rendered anhydrous prior to intermixing with the other ingredients, or water / moisture may be extracted from the mixture during the mixing process to ensure that the resulting sealant composition is substantially anhydrous.

[0004] Silicone sealant compositions having at least one Si-alkoxy bond (e.g., a Si-methoxy bond in a terminal reactive silyl group) and having a polydiorganosiloxane polymeric backbone are widely used as sealants in the construction industry because they have good adhesion and weather resistance, etc. The construction industry also prefers one-component compositions that eliminate the need to mix the components prior to application and compositions with excellent workability.

[0005] However, the application of one-part condensation-curable silicone compositions to substrates such as stone, marble, brick, concrete, cement and other cementitious substrates when the substrate surface is at elevated temperatures, e.g., at least 40° C., is a problem for the construction industry. This is because, although one-part condensation-curable silicone compositions are highly desirable for such purposes, given that they have little or no deleterious effect on the porous substrates to which they are applied and subsequently cured, such compositions (particularly those comprising an organopolysiloxane polymer having at least two alkoxy groups per molecule and a titanate- or zirconate-based catalyst) produce bubbles in the composition during the curing process when the substrate is hot. This often occurs in sunny weather and hot climates when sunlight heats the substrate or associated building materials to temperatures that often exceed 40° C., especially when the sealant used has been stored for several months prior to use. These bubbles are unacceptable and increase the volume of the cured product by as much as two or three times compared to room temperature curing materials that are not cured on hot porous substrates. Additionally, bubbles cause blistering and have a significant negative impact on the adhesion between the cured silicone product (eg, sealant) and the substrate.

[0006] Without being bound by the present theory, it is believed that when an alkoxy silicone composition (typically used as a sealant) is applied to a hot porous substrate (especially to a hydrophilic hot porous substrate) at a temperature of at least 40°C, more and more moisture / water vapor condenses at the interface of the sealant and the porous substrate, which is driven by capillary action and the reactivity of moisture with the composition. This leads to more and more hydrolysis of the alkoxysilyl groups at the interface between the hot porous substrate at at least 40°C, and thus the production of more and more increased alcohol, typically methanol, given the high temperature of the substrate. It is believed that bubbling is a problem because at the high temperature of the substrate, the rate of alcohol (methanol) production at the interface is higher than its permeation rate through the bulk curing composition (e.g., sealant composition). Therefore, bubbles are trapped during curing under these conditions, which is not only because of the process of curing of such compositions, i.e., the initial formation of a skin that prevents the escape of bubbles (especially at elevated temperatures) will cause the skin to form faster than when the sealant is cured at or near room temperature. This is a particular problem when using such compositions as, for example, sealants in countries with hot climates.

[0007] Provided herein is a one-part thermally porous surface condensation-curable silicone composition comprising an organopolysiloxane polymer having at least two alkoxy groups per molecule and a titanate-based or zirconate-based catalyst, wherein the thermally porous substrate is at a temperature of at least 40° C., the one-part thermally porous surface condensation-curable silicone composition comprising the following components:

[0008] (a) an organopolysiloxane polymer having at least two hydroxyl groups or hydrolyzable groups per molecule of the following formula:

[0009] X 3-n R n Si-Z-(R 1 y SiO (4-y) / 2 ) z -SiR 1 2-Z-Si-R n X 3-n (1)

[0010] wherein each X is independently a hydroxyl group or an alkoxy group, each R is an alkyl, alkenyl or aryl group, and each R 1 is an X group, an alkyl group, an alkenyl group or an aryl group and Z is a divalent organic group;

[0011] n is 0 or 1, y is 0, 1 or 2, and preferably 2, and z is an integer such that the organopolysiloxane polymer has a viscosity of 10,000 to 150,000 mPa.s at 25° C., in an amount of 30% by weight of the composition

[0012] to 90 weight % (wt. %);

[0013] (b) one or more reinforcing fillers selected from precipitated silica, fumed silica or precipitated calcium carbonate;

[0014] (c) a silane compound having two hydrolyzable groups per molecule of the following formula:

[0015] R 3 2-Si-R 4 2

[0016] Each group R 3 may be the same or different and are hydrolyzable groups selected from alkoxy or acetoxy groups, and each R 4 The groups are the same or different and independently represent an alkyl group, an alkenyl group, an alkynyl group, an aryl group or a fluorinated alkyl group having 1 to 10 carbon atoms, the silane compound (c) being present in the composition in an amount of 1% to 10% by weight of the composition;

[0017] (d) tetra-n-propoxysilane is present in an amount from 0.40% to 3.5% by weight of the composition;

[0018] (e) a silicon-containing compound having three or more hydrolyzable groups per molecule, selected from

[0019] (e)(a') 1,3,5-Tris(trialkoxysilylalkyl)isocyanurate

[0020] (e) (b') Siloxane oligomers of the following structure

[0021] Si-((O-Si(CH3)2) n’ -(R 7 -Si(CH3)2-O-Si(CH3)2) z’ -R 7 -Si(OR 8 )3)4;

[0022] Each R 7 Can be the same or different and can be the same as R 5 The same and each R 8 Can be the same or different and can be the same as R 6 are the same, n' is an integer and z' is 0 or 1; or

[0023] (e) (c') Siloxane oligomers of the following structures

[0024] R 9 -Si-((O-Si(CH3)2) n’ -(R 7 -Si(CH3)2-O-Si(CH3)2) z’ -R 7 -Si(OR 8 )3)3

[0025] The same R 7 , R 8 n' and z' are as defined above and R 9 Can be used with R 8 Likewise, the silicon-containing compound (e) is present in the composition in an amount of 0.1 wt % to 5 wt % of the composition; and

[0026] (f) A catalyst comprising a titanate-based compound, a zirconate-based compound or a mixture thereof.

[0027] The total weight % of the composition is 100 weight %. The one-part thermal porous surface condensation-curable silicone composition herein is a one-part condensation-curable silicone composition designed to be curable on a substrate at a temperature of at least 40° C. Such a one-part condensation-curable silicone composition contains no or minimal visible bubbles when cured. The one-part thermal porous surface condensation-curable silicone composition comprising an organopolysiloxane polymer having at least two alkoxy groups per molecule and a titanate-based or zirconate-based catalyst can be cured on a thermal porous surface (at least 40° C.) without generating bubbles or generating very few bubbles.

[0028] Also provided herein is an elastomeric sealant material that adheres to a thermally porous substrate at a temperature of at least 40° C., the elastomeric sealant material being the cured product of a composition as described herein. The elastomeric sealant material is free or substantially free of trapped air bubbles.

[0029] Also provided is a method of applying a one-part thermoporous surface condensation-curable silicone composition to a thermoporous substrate at a temperature of at least 40° C., the method comprising the steps of:

[0030] (i) applying a one-part thermal porous surface condensation-curable silicone composition to a thermal porous substrate at a temperature of at least 40° C., wherein the one-part thermal porous surface condensation-curable silicone composition comprises the following components:

[0031] (a) an organopolysiloxane polymer having at least two hydroxyl groups or hydrolyzable groups per molecule of the following formula:

[0032] X 3-n R n Si-Z-(R 1 y SiO (4-y) / 2 ) z –SiR 1 2-Z-Si-R n X 3-n (1)

[0033] wherein each X is independently a hydroxyl group or an alkoxy group, each R is an alkyl, alkenyl or aryl group, and each R 1 is an X group, an alkyl group, an alkenyl group or an aryl group and Z is a divalent organic group;

[0034] n is 0 or 1, y is 0, 1 or 2, and preferably 2, and z is an integer such that the organopolysiloxane polymer has a viscosity of 10,000 to 150,000 mPa.s at 25°C, in an amount of 30 to 90 weight percent (wt.%) of the composition;

[0035] (b) one or more reinforcing fillers selected from precipitated silica, fumed silica or precipitated calcium carbonate;

[0036] (c) a silane compound having two hydrolyzable groups per molecule of the following formula:

[0037] R 3 2-Si-R 4 2

[0038] Each group R 3 may be the same or different and are hydrolyzable groups selected from alkoxy or acetoxy groups, and each R 4The groups are the same or different and independently represent an alkyl group, an alkenyl group, an alkynyl group, an aryl group or a fluorinated alkyl group having 1 to 10 carbon atoms, the silane compound (c) being present in the composition in an amount of 1% to 10% by weight of the composition;

[0039] (d) tetra-n-propoxysilane is present in an amount from 0.40% to 3.5% by weight of the composition;

[0040] (e) a silicon-containing compound having three or more hydrolyzable groups per molecule, selected from

[0041] (e) (a') 1,3,5-tris(trialkoxysilylalkyl)isocyanurate (e) (b') Siloxane oligomer of the following structure

[0042] Si-((O-Si(CH3)2) n’ -(R 7 -Si(CH3)2-O-Si(CH3)2) z’ -R 7 -Si(OR 8 )3)4;

[0043] Each R 7 Can be the same or different and can be the same as R 5 The same and each R 8 Can be the same or different and can be the same as R 6 are the same, n' is an integer and z' is 0 or 1; or

[0044] (e) (c') Siloxane oligomers of the following structures

[0045] R 9 -Si-((O-Si(CH3)2) n’ -(R 7 -Si(CH3)2-O-Si(CH3)2) z’ -R 7 -Si(OR 8 )3)3

[0046] The same R 7 , R 8 n' and z' are as defined above and R 9 Can be used with R 8 Likewise, the silicon-containing compound (e) is present in the composition in an amount of 0.1 wt % to 5 wt % of the composition; and

[0047] (f) a catalyst comprising a titanate-based compound, a zirconate-based compound or a mixture thereof; and

[0048] (ii) curing the composition.

[0049] A method for bonding a silicone sealant to a thermal porous substrate at a temperature of at least 40°C, comprising the steps of preparing a one-part thermal porous surface condensation-curable silicone composition as described above, contacting the surface of the thermal porous substrate with the one-part thermal porous surface condensation-curable silicone composition at a temperature of at least 40°C, and curing the one-part thermal porous surface condensation-curable silicone composition to obtain a silicone sealant bonded to the surface of the thermal porous substrate.

[0050] A sealant that bonds to a thermoporous substrate at a temperature of at least 40°C is obtained or can be obtained by preparing a one-part thermoporous surface condensation-curable silicone composition as described above, contacting the surface of the thermoporous substrate with the one-part thermoporous surface condensation-curable silicone composition at a temperature of at least 40°C, and curing the one-part thermoporous surface condensation-curable silicone composition.

[0051] Use of a one-part thermally porous surface condensation-curable silicone composition comprising:

[0052] (a) an organopolysiloxane polymer having at least two hydroxyl groups or hydrolyzable groups per molecule of the following formula:

[0053] X 3-n R n Si-Z-(R 1 y SiO (4-y) / 2 ) z -SiR 1 2-Z-Si-R n X 3-n (1)

[0054] wherein each X is independently a hydroxyl group or an alkoxy group, each R is an alkyl, alkenyl or aryl group, and each R 1 is an X group, an alkyl group, an alkenyl group or an aryl group and Z is a divalent organic group;

[0055] n is 0 or 1, y is 0, 1 or 2, and preferably 2, and z is an integer such that the organopolysiloxane polymer has a viscosity of 10,000 to 150,000 mPa.s at 25° C., in an amount of 30% by weight of the composition

[0056] to 90 weight % (wt. %);

[0057] (b) one or more reinforcing fillers selected from precipitated silica, fumed silica or precipitated calcium carbonate;

[0058] (c) a silane compound having two hydrolyzable groups per molecule of the following formula:

[0059] R 3 2-Si-R 4 2

[0060] Each group R 3 may be the same or different and are hydrolyzable groups selected from alkoxy or acetoxy groups, and each R 4 The groups are the same or different and independently represent an alkyl group, an alkenyl group, an alkynyl group, an aryl group or a fluorinated alkyl group having 1 to 10 carbon atoms, the silane compound (c) being present in the composition in an amount of 1% to 10% by weight of the composition;

[0061] (d) tetra-n-propoxysilane is present in an amount from 0.40% to 3.5% by weight of the composition;

[0062] (e) a silicon-containing compound having three or more hydrolyzable groups per molecule, selected from

[0063] (e)(a') 1,3,5-Tris(trialkoxysilylalkyl)isocyanurate

[0064] (e) (b') Siloxane oligomers of the following structure

[0065] Si-((O-Si(CH3)2) n’ -(R 7 -Si(CH3)2-O-Si(CH3)2) z’ -R 7 -Si(OR 8 )3)4;

[0066] Each R 7 Can be the same or different and can be the same as R 5 The same and each R 8 Can be the same or different and can be the same as R 6 are the same, n' is an integer and z' is 0 or 1; or

[0067] (e) (c') Siloxane oligomers of the following structures

[0068] R 9 -Si-((O-Si(CH3)2) n’ -(R 7 -Si(CH3)2-O-Si(CH3)2) z’ -R 7 -Si(OR 8 )3)3

[0069] The same R 7 , R 8 n' and z' are as defined above and R 9 Can be used with R 8 Likewise, the silicon-containing compound (e) is present in the composition in an amount of 0.1 wt % to 5 wt % of the composition; and

[0070] (f) a catalyst comprising a titanate-based compound, a zirconate-based compound or a mixture thereof;

[0071] As a means for applying a sealant to a hot porous substrate at a temperature of at least 40°C while minimizing the entrapment of air bubbles in the resulting cured sealant upon curing of the composition on the surface of the hot porous substrate.

[0072] Also provided is the use of the aforementioned composition as a sealant in the fields of facades, insulating glass, window construction, automotive, solar energy and construction.

[0073] Also provided is a method for filling a space between two substrates to create a seal between the two substrates, the method comprising:

[0074] a″) providing the silicone composition as described above, and

[0075] b") applying a one-part thermal porous surface condensation-curable silicone composition to a first substrate at a temperature of at least 40°C and contacting a second substrate with the silicone composition applied to the first substrate, wherein either or both of the substrates are porous substrates, or

[0076] c") filling a space formed by the arrangement of a first substrate and a second substrate with a one-part thermal porous surface condensation-curable silicone composition at a temperature of at least 40°C, wherein one or both of the substrates are porous substrates, and

[0077] d") curing the silicone composition.

[0078] Preferably, the first substrate and / or the second substrate is stone, marble, brick, concrete, cement and other cementitious substrates, combinations thereof, or combinations with other non-porous building materials.

[0079] As used herein, the concept “comprising” is used in its broadest sense to mean and encompass the concepts “including” and “consisting of.”

[0080] For the purposes of this application, "substituted" means that one or more hydrogen atoms in a hydrocarbon group are replaced by another substituent. Examples of such substituents include, but are not limited to, halogen atoms such as chlorine, fluorine, bromine, and iodine; groups containing halogen atoms such as chloromethyl, perfluorobutyl, trifluoroethyl, and nonafluorohexyl; oxygen atoms; groups containing oxygen atoms such as (meth)acrylic acid and carboxyl; nitrogen atoms; groups containing nitrogen atoms such as amino functional groups, amido functional groups, and cyano functional groups; sulfur atoms; and groups containing sulfur atoms such as mercapto groups.

[0081] The one-part hot porous surface condensation-curable silicone composition suitable for application to a porous substrate at a temperature of at least 40°C is designed for the purpose of bonding it to the surface of a hot porous substrate, such as stone, marble, brick, concrete, cement and other cementitious substrates, combinations thereof, and combinations with other non-porous building materials. The one-part hot porous surface condensation-curable silicone composition can also be used to bond a combination of hot porous surfaces together, as well as to bond with other conventional building materials (such as glass and aluminum). The one-part hot porous surface condensation-curable silicone composition is contacted with the hot porous surface by conventional means such as by extrusion, coating, injection, doctoring and rolling. The one-part hot porous surface condensation-curable silicone composition is particularly intended to be used when the surface of the porous substrate to which it is applied is at a temperature of at least 40°C. Some bubbles may form on porous surfaces at temperatures below 40°C, but when the method described herein is used, the reduction of bubbles at temperatures of 40°C or higher is significant. After the one-part thermal porous surface condensation-curable silicone composition is applied to the thermal porous substrate, it is exposed to atmospheric moisture, causing it to cure into a silicone sealant bonded to the surface of the thermal porous substrate, wherein the number and size of bubbles in the cured silicone sealant are reduced compared to applying a standard RTV silicone sealant to the thermal porous substrate at 40°C or higher. Therefore, it can be said that the one-part thermal porous surface condensation-curable silicone composition as described herein can be cured on a thermal porous surface (at least 40°C) while reducing bubble generation. Undesirable bubbles are mainly formed at the interface between the thermal porous substrate and the cured silicone surface. The ambient temperature for which the sealant composition is designed to cure is significantly higher than that usually designed (e.g., >10°C), and therefore the curing time and working time of most standard sealant formulations will be shorter than usual. However, compared to standard sealant compositions, the one-part thermal porous surface condensation-curable silicone composition herein has an increased working time at a temperature of 40°C or higher. The components of the composition will now be described in more detail.

[0082] An organopolysiloxane polymer (a) having at least two hydroxyl groups or hydrolyzable groups per molecule

[0083] The organopolysiloxane polymer (a) having at least two hydroxyl groups or hydrolyzable groups per molecule has the following formula:

[0084] X 3-n R n Si-Z-(R 1 y SiO (4-y) / 2 ) z –SiR 1 2-Z-Si-R n X 3-n (1)

[0085] In the above formula, each X is independently a hydroxyl group or an alkoxy group, alternatively an alkoxy group. Preferably, the alkoxy group has between 1 and 10 carbons, exemplary alkoxy groups are methoxy, ethoxy, propoxy, isopropoxy, n-butoxy, tert-butoxy, isobutoxy, pentyloxy, hexyloxy and 2-ethylhexyloxy; dialkoxy groups such as methoxymethoxy or ethoxymethoxy, and alkoxyaryloxy such as ethoxyphenoxy groups; alternatively, each X is an alkoxy group having one to six carbons, alternatively one to four carbons, or alternatively a methoxy or ethoxy group.

[0086] Each R group is an alkyl, alkenyl or aryl group, alternatively each R is an alkyl group with 1 to 6 carbons, an alkenyl group with 2 to 6 carbons (such as vinyl, allyl and hexenyl groups) or an aryl group with 6 to 12 carbons; alternatively each R is an alkyl group with 1 to 6 carbons, or an aryl group with 6 to 12 carbons; alternatively each R is an alkyl group with 1 to 6 carbons, alternatively each R is an ethyl group or a methyl group. In one embodiment, R may include a substituted aliphatic organic group, such as a 3,3,3-trifluoropropyl group, an aminoalkyl group, a polyaminoalkyl group and / or an alkylene oxide group.

[0087] Each R 1 is an X group, or and an R group, provided that cumulatively at least two X groups and / or R groups per molecule 1 The group is a hydroxyl group or a hydrolyzable group, alternatively each R 1 is an R group. It is possible that some R 1 The groups may be siloxane branches branching from the polymer backbone and these branches may have terminal groups as described above.

[0088] Each Z is a divalent organic group, typically an alkylene group having 2 to 10 carbons, such as, for example, ethylene, propylene, butylene, pentylene and / or hexylene groups; alternatively an alkylene group having 2 to 6 carbons, alternatively an alkylene group having 2 to 5 carbons. Subscript n is zero or 1, alternatively zero; each subscript y is 0, 1 or 2, and preferably 2. Although y is 0, 1 or 2, substantially y=2, for example at least 90%, alternatively 95%, of R 1 y SiO (4-y) / 2 The group is characterized in that y=2. The subscript z is an integer such that the organopolysiloxane polymer has a viscosity of 10,000 mPa.s to 150,000 mPa.s, alternatively 30,000 mPa.s to 140,000 mPa.s at 25°C, so z is an integer from about 300 to 2000. The viscosity of the component can be measured by any suitable method, such as according to corporate test method CTM 0050, which is publicly available and based on ASTM D1084-16 method B, using a Brookfield HBDV-III Ultra rheometer equipped with cone plate geometry, using spindle 52. Unless otherwise specified, all viscosity measurements herein are obtained at 25°C. Alternatively, viscosity can be measured using a Modular Compact Rheometer (MCR) 302 rheometer from Anton Paar GmbH of Graz, Austria, using the most appropriate settings and plates for the viscosities involved. For example, viscosities in the range of 30,000 mPa.s to 160,000 mPa.s can be measured using a cone plate with a 40 mm diameter and a 1 s -1 The shear rate can be measured with an MCR 302 rheometer; the viscosity in the range of 2000 mPa.s-30,000 mPa.s can be measured using a cone plate with a diameter of 50 mm and a 1 s -1 The shear rate can be measured by an MCR 302 rheometer; and the viscosity in the range of 10 mPa.s-2000 mPa.s can be measured using a cone plate with a diameter of 75 mm and a 1 s -1 The shear rate was measured using an MCR 302 rheometer.

[0089] Component (a) is present in the one-part thermally porous surface condensation-curable silicone composition in an amount of 30 to 90 wt %, alternatively 35 to 75 wt %, alternatively 35 to 60 wt % of the composition.

[0090] The organopolysiloxane polymer (a) may be a single siloxane represented by formula (1), or it may be a mixture of organopolysiloxane polymers represented by the above formula. Therefore, it may be a "siloxane polymer mixture", so the organopolysiloxane polymer (a) is meant to include any single organopolysiloxane polymer (a) or a mixture of organopolysiloxane polymers (a).

[0091] The degree of polymerization (DP) (i.e., essentially z in the above formula) is generally defined as the number of monomer units in a macromolecule or polymer or oligomer molecule of an organosilicon. Synthetic polymers always consist of a mixture of macromolecular species with different degrees of polymerization and therefore different molecular weights. There are different types of average polymer molecular weights, which can be measured in different experiments. The two most important average polymer molecular weights are the number average molecular weight (Mn) and the weight average molecular weight (Mw). The Mn and Mw of organosilicon polymers can be determined by gel permeation chromatography (GPC) using polystyrene standards with an accuracy of about 10% to 15%.

[0092] The technique is standard and produces Mw, Mn and polydispersity index (PI). Degree of polymerization (DP) = Mn / Mu, where Mn is the number average molecular weight measured from GPC, and Mu is the molecular weight of the monomer unit. PI = Mw / Mn. DP is associated with the viscosity of the polymer via Mw, and the higher the DP, the higher the viscosity. In the present disclosure, the number average molecular weight and weight average molecular weight values ​​of component (a) herein can be measured, for example, using a Waters 2695 separation module (Waters Corporation of MA, USA) equipped with a vacuum degasser and a Waters 2414 refractive index detector. Certified grade toluene flowing at 1.0 mL / min can then be used as an eluent for analysis. Data collection and analysis can be performed using Waters Empower GPC software.

[0093] One or more reinforcing fillers (b)

[0094] The one or more reinforcing fillers identified herein as component (b) are selected from precipitated silica, fumed silica, precipitated calcium carbonate or a mixture of two or more thereof. Typically, the surface area of ​​the reinforcing filler (b) measured according to the BET method (ISO 9277:2010) is at least 15 m 2 / g, alternatively 15m 2 / g to 50m 2 / g, alternatively 15m 2 / g to 25m 2 / g.

[0095] According to the BET method (ISO 9277:2010), the typical surface area of ​​silica reinforcing fillers is at least 50 m 2 In the case of high surface area fumed silica and / or high surface area precipitated silica, the surface area of ​​these high surface area fumed silica and / or high surface area precipitated silica may be 75 m2 / s as measured according to the BET method (ISO 9277:2010). 2 / g to 400m 2 / g, alternatively 100 m / s measured according to the BET method (ISO 9277:2010) 2 / g to 300m 2 / g.

[0096] The reinforcing filler (b) may be treated with hydrophobicity, for example, with one or more aliphatic acids (e.g., fatty acids such as stearic acid, or fatty acid esters such as stearic acid esters), or with organosilanes, organosiloxanes, or organosilazane hexaalkyldisilazane or short-chain siloxane diols, so that the filler is hydrophobic and thus easier to handle and obtain a uniform mixture with other adhesive components. Specific examples of organosilanes, organosiloxanes or organosilazanes include, but are not limited to, silanol-terminated trifluoropropylmethylsiloxane, silanol-terminated vinylmethyl (ViMe) siloxane, silanol-terminated methylphenyl (MePh) siloxane, liquid hydroxydimethyl-terminated polydiorganosiloxanes containing an average of 2 to 20 repeating units of diorganosiloxane per molecule, hydroxydimethyl-terminated phenylmethylsiloxane, hexaorganodisiloxanes such as hexamethyldisiloxane, divinyltetrasiloxane, dimethyl ... Methyldisiloxanes; hexaorganodisilazanes such as hexamethyldisilazane (HMDZ), divinyltetramethyldisilazane and tetramethylbis(trifluoropropyl)disilazane; hydroxydimethyl terminated polydimethylmethylvinylsiloxane, octamethylcyclotetrasiloxane and silanes including but not limited to methyltrimethoxysilane, dimethyldimethoxysilane, vinyltrimethoxysilane, methyltriethoxysilane, vinyltriethoxysilane, trimethylchlorosilane, dimethyldichlorosilane, trichloromethylsilane.

[0097] The surface treatment of the filler makes it easy to be wetted by component (a). These surface modified fillers are preferably in finely divided form and do not agglomerate, and can be uniformly incorporated into the silicone polymer (a). This results in improved room temperature mechanical properties of the uncured composition. When mixed with component (a), the filler can be pre-treated or can be treated in situ. A small amount of water can be added with the silica treatment agent as a processing aid.

[0098] Depending on the selected filler, the reinforcing filler (b) can be present in an amount of 2.5% to 60% by weight (wt.%) of the single-part thermal porous surface condensation-curable silicone composition. In the case where the selected filler is precipitated silica and / or fumed silica or a combination thereof, the inorganic filler (b) is present in a range of about 5.0% to 35% by weight of the composition, alternatively 5% to 30% by weight of the composition, alternatively 5% to 25% by weight of the composition. However, when the reinforcing filler (b) is precipitated calcium carbonate, the composition will tend to include a larger wt% of the composition, such as 25% to 60% by weight of the composition, alternatively 30% to 60% by weight of the composition, alternatively 35% to 55% by weight of the composition. When component (b) is a mixture of silica and precipitated calcium carbonate, the wt% will generally be between them.

[0099] Silane compound (c) having two hydrolyzable groups per molecule

[0100] Component (c) is a silane having two hydrolyzable groups per molecule of the formula:

[0101] R 3 2-Si-R 4 2

[0102] Each group R 3 can be the same or different and are hydroxyl or hydrolyzable groups. 3 Examples of the group may be selected from alkoxy or acetoxy groups. Most preferably, the reactive group is an alkoxy group having 1 to 10 carbon atoms, such as methoxy, ethoxy, propoxy, isopropoxy, butoxy, and tert-butoxy. Each R 4 The groups are the same or different and independently represent an alkyl group, an alkenyl group (such as vinyl, propenyl and hexenyl groups), an alkynyl group and an aryl group (such as phenyl) or a fluorinated alkyl group having 1 to 10 carbon atoms. Specific examples of suitable silanes for component (c) include: -

[0103] Alkenylalkyldialkoxysilanes such as vinylmethyldimethoxysilane, vinylethyldimethoxysilane, vinylmethyldiethoxysilane and vinylethyldiethoxysilane; dialkyldialkoxysilanes such as dimethyldimethoxysilane, diethyldimethoxysilane, dimethyldiethoxysilane and diethyldiethoxysilane; dialkenyldialkoxysilanes such as divinyldimethoxysilane, divinyldimethoxysilane, divinyldiethoxysilane and divinyldiethoxysilane; phenylalkyldialkoxysilanes such as phenylmethyldimethoxysilane, phenylethyldimethoxysilane, phenylmethyldiethoxysilane and phenylethyldiethoxysilane; alkenylphenyldialkoxysilanes such as vinylphenyldimethoxysilane, vinylphenyldimethoxysilane, vinylphenyldiethoxysilane and vinylphenyldiethoxysilane.

[0104] Component (c) may alternatively be a diacetoxysilane equivalent as described above or a dihydroxy equivalent of di-3,3,3-trifluoropropyldimethoxysilane as described above. Component (c) may alternatively be a mixture of two or more of the above.

[0105] Component (c) is present in a range of 1 wt % to 10 wt % of the one-part thermal porous surface condensation-curable silicone composition, alternatively 1.25 wt % to 7.5 wt % of the composition, alternatively 1.5 wt % to 4.0 wt % of the composition.

[0106] Tetrapropoxysilane (d)

[0107] Component (d) is tetra-n-propoxysilane (TPOS) having the following structure:

[0108] Si-(O-CH2CH2CH3)4

[0109] Surprisingly, it has been found that the addition of a tetra-n-propoxysilane component (d) to a one-part room temperature vulcanizable (RTV) silicone composition appears to solve the long-standing industrial problem of bubbling when such sealant compositions are applied to substrates such as stone, marble, brick, concrete, cement and other cementitious substrates at temperatures of at least 40°C in countries with high temperature climates (>40°C). The introduction of the tetra-n-propoxysilane (component (d)) significantly and unexpectedly reduces the number and size of bubbles generated under such circumstances. It has been found that component (d) needs to be present in an amount of 0.40 wt % to 3.5 wt % of the one-part thermal porous surface condensation-curable silicone composition, alternatively 0.40 wt % to 3.0 wt % of the composition, alternatively 0.40 wt % to 2.5 wt % of the composition, alternatively 0.40 wt % to 2.5 wt % of the composition, alternatively 0.50 wt % to 2.0 wt % of the composition.

[0110] Component (e)

[0111] Component (e) of the one-part thermal porous surface condensation curable silicone composition is a silicon-containing compound selected from the group consisting of:-

[0112] (e) (a') 1,3,5-tris(trialkoxysilylalkyl)isocyanurate, for example, 1,3,5-tris(trialkoxysilylalkyl)isocyanurate having the following structure:

[0113]

[0114] Each R 5 may be the same or different and are divalent alkylene groups having 2 to 10 carbons, alternatively 2 to 6 carbons, alternatively 2 to 5 carbons, and each R 6 The same or different and are alkyl groups having 1 to 10 carbons, alternatively 1 to 6 carbons, alternatively 1 to 4 carbons, alternatively a methyl group or an ethyl group.

[0115] Typically, (e)(a') 1,3,5-tris(trialkoxysilylalkyl)isocyanurates can be prepared by the reaction of chloroalkyltrialkoxysilanes with alkali metal cyanates in polar aprotic solvents. For example, preferred 1,3,5-tris(trialkoxysilylalkyl)isocyanurates (e)(a') are prepared by the reaction of chloropropyltrimethoxysilane with potassium cyanate in a suitable solvent such as dimethylformamide (DMF). This results in the production of a 1,3,5-tris(trialkoxysilylalkyl)isocyanurate wherein each R 5 is a propylene group and each R 6 isocyanurate which is a methyl group, ie, tris-(trimethoxysilylpropyl)isocyanurate as depicted below.

[0116]

[0117] Alternatively, the silicon-containing compound may be (e)(b') and / or (e)(c').

[0118] Wherein (e)(b') is a siloxane oligomer of the following structure:

[0119] Si-((O-Si(CH3)2) n’ -(R 7 -Si(CH3)2-O-Si(CH3)2) z’ -R 7 -Si(OR 8 )3)4;

[0120] Each R 7 Can be the same or different and can be the same as R 5 The same and each R8 Can be the same or different and can be the same as R 6 are the same, n' is an integer and z' is 0 or 1; or

[0121] (e) (c') Siloxane oligomers of the following structures

[0122] R 9 -Si-((O-Si(CH3)2) n’ -(R 7 -Si(CH3)2-O-Si(CH3)2) z’ -R 7 -Si(OR 8 )3)3

[0123] The same R 7 , R 8 n' and z' are as defined above, and R 9 Can be used with R 8 The same or may be an aryl group or a fluorinated alkyl group.

[0124] In one embodiment, in (e)(b') or (e)(c'), each R 7 may be the same or different and may be a divalent alkylene group having 2 to 5 carbon atoms, each R 8 may be the same or different and contain from 1 to 5 carbon atoms, alternatively each R 7 The same and may be the same or different and may be a divalent alkylene group having 2 to 5 carbon atoms, each R 8 may be the same or different and contain from 1 to 5 carbon atoms, alternatively each R 7 are the same and contain two or three carbons (2 or 3), alternatively 2 carbons, each R 8 are the same and have 1 to 3 carbons, alternatively are methyl or ethyl, alternatively are methyl and z' is 1. The subscript n' is an integer, alternatively each n' is an integer from 1 to 1000, alternatively from 2 to 750. In the case of (e) (c'), R 9 Preferably R 8 or R 8 , or may be an aryl group or a fluorinated alkyl group.

[0125] Components (e) act as crosslinking agents and, in view of their structure, are designed to provide a cured sealant with high elasticity and low modulus.

[0126] It is understood that each of (e)(a'), (e)(b') or (e)(c') has three or more trialkoxysilyl terminal groups per molecule.

[0127] The silicon-containing compound (e) is present in an amount of 0.1 wt % to 5 wt % of the one-part thermally porous surface condensation-curable silicone composition, alternatively in an amount of 0.1 wt % to 4 wt % of the composition, alternatively in an amount of 0.1 wt % to 2.5 wt % of the composition, alternatively in an amount of 0.1 wt % to 1.5 wt % of the composition, alternatively in an amount of 0.1 wt % to 1.0 wt % of the composition.

[0128] Catalyst (f) comprising a titanate-based compound, a zirconate-based compound or a mixture thereof

[0129] Component (f) comprises a condensation catalyst (iv) which increases the rate at which the composition cures. The titanate-based and / or zirconate-based catalyst may comprise a catalyst according to the general formula Ti[OR 22 ]4 or Zr[OR 22 ]4, wherein each R 22 may be identical or different and represent a monovalent primary, secondary or tertiary aliphatic hydrocarbon group, which may be linear or branched and contain 1 to 10 carbon atoms. Optionally, the titanate may contain partially unsaturated groups. However, R 22 Preferred examples include, but are not limited to, methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, and branched secondary alkyl groups such as 2,4-dimethyl-3-pentyl. 22 The same, and R 22 is isopropyl, a branched secondary alkyl group or a tertiary alkyl group, in particular tert-butyl.

[0130] For purposes of illustration, suitable examples include tetra-n-butyl titanate, tetra-tert-butyl titanate, tetra-tert-butoxy titanate, tetra-isopropoxy titanate, and zirconate equivalents.

[0131] Alternatively, the titanate may be chelated. Chelation may employ any suitable chelating agent, such as alkyl acetylacetonates, such as methyl acetylacetonate or ethyl acetylacetonate. Alternatively, the titanate may be a monoalkoxy titanate with three chelating agents, such as 2-propanol, triisooctadecanoic acid titanate and diisopropoxy diethyl acetoacetic acid titanate or ethyl acetoacetic acid titanium complex mixed with methyl-trimethoxysilane. Component (f) may be present in any suitable amount, such as 0.05 wt % to 1.5 wt % of a single-part thermally porous surface condensation-curable silicone composition, alternatively 0.05 wt % to 1.25 wt % of the composition, alternatively 0.1 wt % to 1.0 wt % of the composition, alternatively 0.1 wt % to 0.75 wt % of the composition.

[0132] Components (c) + (d) + (e) are cumulatively present in the one-part thermal porous surface condensation-curable silicone composition in a range of 1.5 wt % to 18.5 wt % of the composition. Alternatively, components (c) + (d) + (e) may be cumulatively present in a range of 1.5 wt % to 10 wt % of the composition; alternatively, components (c) + (d) + (e) may be cumulatively present in a range of 2.0 wt % to 7.5 wt % of the composition; alternatively, components (c) + (d) + (e) may be cumulatively present in a range of 2.5 wt % to 7.5 wt % of the composition.

[0133] Optional additives

[0134] Optional additives may be used if desired. These additives may include non-reinforcing fillers, pigments, rheology modifiers, cure modifiers, adhesion promoters, tin (IV) condensation catalysts, and fungicides and / or biocides, among others; it should be understood that some of these additives may be included in more than one additive list. Such additives will then have the ability to function in the different ways involved.

[0135] Non-reinforcing fillers

[0136] Non-reinforcing fillers that may be used in addition to component (b) herein include bauxite, calcium sulfate (anhydrite), gypsum, nepheline, syenite, quartz, calcium sulfate, magnesium carbonate, ground calcium carbonate, clays such as kaolin, alumina trihydrate, magnesium hydroxide (brucite), graphite, copper carbonates such as malachite, nickel carbonates such as trevally, barium carbonates such as witherite, and / or strontium carbonates such as strontianite.

[0137] Alumina, silicates selected from the group consisting of: olivines; garnets; aluminosilicates; cyclosilicates; inosilicates; and sheet silicates. Olivines include silicate minerals such as, but not limited to, forsterite and Mg2SiO4. Garnets include ground silicate minerals such as, but not limited to, pyrope; Mg3Al2Si3O 12 ; grossular garnet; and Ca2Al2Si3O 12 Aluminosilicates include ground silicate minerals such as, but not limited to, sillimanite; Al2SiO5; mullite; 3Al2O3.2SiO2; kyanite; and Al2SiO5.

[0138] Cyclosilicates include silicate minerals such as, but not limited to, cordierite and Al3(Mg,Fe)2[Si4AlO 18 ]. Inosilicates include ground silicate minerals such as, but not limited to, wollastonite and Ca[SiO3].

[0139] Sheet silicates include silicate minerals such as, but not limited to, mica; K2AI 14 [Si6Al2O 20 ](OH)4; pyrophyllite; Al4[Si8O 20 ](OH)4; Talc; Mg6[Si8O 20 ](OH)4; serpentine, such as asbestos; kaolinite; Al4[Si4O 10 ](OH)8; and vermiculite.

[0140] Such additional fillers can also be hydrophobically treated in the same manner as above-mentioned component (b). When present, non-reinforcing fillers tend to be used to replace some components (b), so when component (b) reinforcing filler is precipitated calcium carbonate and non-reinforcing filler is also present in composition, the total amount of precipitated calcium carbonate and non-reinforcing filler will still not exceed the upper limit 60 wt % of composition. In one embodiment of composition, when component (b) is precipitated calcium carbonate, said composition also comprises heavy calcium carbonate. When present, non-reinforcing filler can exist with an amount greater than zero wt % to 20 wt % of composition.

[0141] pigment

[0142] The one-part thermal porous surface condensation-curable silicone composition as described herein may also include one or more pigments and / or colorants, which may be added if desired. The pigments and / or colorants may be colored, white, black, metallic, and luminescent, such as fluorescent and phosphorescent. The composition may be colored using pigments as desired. Any suitable pigment may be used that provides compatibility with the composition herein. In the one-part thermal porous surface condensation-curable silicone composition, pigments and / or colored (non-white) fillers such as carbon black may be used in the catalyst package to color the final sealant product.

[0143] Suitable white pigments and / or colorants include titanium dioxide, zinc oxide, lead oxide, zinc sulfide, lithopone, zirconium oxide, and antimony oxide.

[0144] Suitable non-white inorganic pigments and / or colorants include, but are not limited to, iron oxide pigments such as goethite, lepidocrocite, hematite, maghemite and maghemite black, yellow, brown and red iron oxides; blue iron pigments; chromium oxide pigments; cadmium pigments such as cadmium yellow, cadmium red and cadmium cinnabar; bismuth pigments such as bismuth vanadate and bismuth vanadate molybdate; mixed metal oxide pigments such as cobalt titanate green; chromate and molybdate pigments such as chrome yellow, molybdenum red and molybdenum orange; ultramarine pigments; cobalt oxide pigments; nickel antimony titanate; lead chromium; carbon black (when present, carbon black will act as both a non-reinforcing filler and a colorant); lamp black and metallic effect pigments such as aluminum, copper, copper oxide, bronze, stainless steel, nickel, zinc and brass.

[0145] Suitable organic non-white pigments and / or colorants include phthalocyanine pigments such as phthalocyanine blue and phthalocyanine green; monoarylate yellows, diarylate yellows, benzimidazolone yellows, heterocyclic yellows, DAN oranges, quinacridone pigments such as quinacridone magenta and quinacridone violet; organic reds including metallized azo reds and non-metallized azo reds as well as other azo pigments, monoazo pigments, diazo pigments, azo pigment lakes, β-naphthol pigments, naphthol AS pigments, benzimidazolone pigments, diazo condensation pigments, isoindolinone and isoindolinone pigments, polycyclic pigments, perylene and perindole pigments, thioindigo pigments, anthrapyrimidone pigments, flavonoid pigments, anthraquinone pigments, dioxazine pigments, triarylcarbonium pigments, quinophthalone pigments, and diketopyrrolopyrrole pigments.

[0146] Typically, the pigment and / or colorant, when particulate, has an average particle size in the range of 10 nm to 50 μm, preferably in the range of 40 nm to 2 μm. When present, the pigment and / or colorant is present in the range of 2 wt%, alternatively 3 wt%, alternatively 5 wt% to 20 wt% of the composition.

[0147] Rheology Modifiers

[0148] Rheology modifiers that can be incorporated into the one-part thermal porous surface condensation curable silicone composition include silicone organic copolymers, such as those described in EP0802233 based on polyether or polyester polyols; nonionic surfactants selected from the group consisting of polyethylene glycol, polypropylene glycol, ethoxylated castor oil, oleic acid ethoxylates, alkylphenol ethoxylates, copolymers of ethylene oxide and propylene oxide, and silicone polyether copolymers; and silicone diols. For some systems, these rheology modifiers, especially copolymers of ethylene oxide and propylene oxide and silicone polyether copolymers, can enhance adhesion to substrates, especially plastic substrates.

[0149] Tackifier

[0150] The one-part thermal porous surface condensation-curable silicone composition as described above may also include an aminosilane adhesion promoter having two or three hydroxyl or alkoxy groups per molecule. The aminosilane adhesion promoter having two or three hydroxyl or alkoxy groups per molecule may include aminopropyltriethoxysilane or aminopropyltrimethoxysilane or may include:

[0151] R 10 k (R 11 O) 3-k Si-Z 1 -N(H)-(CH2) m -NH2

[0152] Where R 10 is an alkyl group containing 1 to 10 carbon atoms; each R 11 May be the same or different and be H or R 10 , Z 1 is a straight or branched alkylene group having 2 to 10 carbon atoms, m is 2 to 10, and k is zero or 1.

[0153] R 10 is an alkyl group containing 1 to 10 carbon atoms, or R 10 is an alkyl group containing 1 to 6 carbon atoms, alternatively R 10 is a methyl group or an ethyl group. 11 can be the same or different, and each R 11 may be the same or different and be H or R or R 10 , alternatively, each R 11 For R 10 In an alternative embodiment, all R 11 The groups are the same. 11 When the groups are the same, it is preferred that they are methyl or ethyl groups. 1 is a straight chain or branched alkylene group having 2 to 10 carbon atoms, alternatively 2 to 6 carbon atoms, for example Z 1 It can be a propylene group, a butylene group or an isobutylene group. There can be 2 to 10m groups, in an alternative, m can be 2 to 6, in another alternative, m can be 2 to 5, in yet another alternative, m can be 2 or 3, or m is 2.

[0154] Specific examples include, but are not limited to, aminopropyltriethoxysilane, aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminoisobutylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-2-aminoethylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminoisobutylethyldimethoxysilane, N-(2-aminoethyl)-2-aminoethylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminoisobutylethyldimethoxysilane, N-(2-aminoethyl)-2-aminoethylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldiethoxysilane, and N-(2-aminoethyl)-2-aminoethylmethyldiethoxysilane. Oxysilane, N-(2-aminoethyl)-3-aminoisobutylethyldiethoxysilane, N-(2-aminoethyl)-2-aminoethylmethyldiethoxysilane, N-(2-aminoethyl)-3-aminopropylmethylmethoxyethoxysilane, N-(2-aminoethyl)-2-aminoethylmethylmethoxyethoxysilane, N-(2-aminoethyl)-3-aminoisobutylethylmethoxyethoxysilane, N-(2-aminoethyl)-2-aminoethylmethylmethoxyethoxysilane, N-(2-aminopropyl)-3-aminoisobutylmethyldimethoxysilane, N-(2-aminopropyl)-3-aminoisobutylmethyldimethoxysilane Aminopropylmethyldimethoxysilane, N-(2-aminopropyl)-2-aminoethylmethyldimethoxysilane, N-(2-aminopropyl)-3-aminoisobutylethyldimethoxysilane, N-(2-aminopropyl)-2-aminoethylmethyldimethoxysilane, N-(2-aminopropyl)-3-aminopropylmethyldiethoxysilane, N-(2-aminopropyl)-2-aminoethylmethyldiethoxysilane, N-(2-aminopropyl)-3-aminoisobutylethyldiethoxysilane, N-(2-aminopropyl)-2-aminoethylmethyldiethoxysilane, N-(2-aminopropyl)-3-aminoisobutylethyldiethoxysilane The invention also includes 3-(2-aminoethyl)-aminopropyltriethoxysilane, 3-(2-aminoethyl)-aminopropyltrimethoxysilane, N-(3-(trimethoxysilyl)propyl)butylamine and bis(trimethoxysilylpropyl)amine.

[0155] When present, the tackifier is present in an amount from 0.1% to 3.75% by weight of the composition, alternatively from 0.1% to 2.5% by weight of the composition, alternatively from 0.1% to 2.0% by weight of the composition, alternatively from 0.2% to 1.0% by weight of the composition.

[0156] Tin(IV) Catalyst

[0157] Preferably, the only condensation cure catalyst present in the one-part thermally porous surface condensation-curable silicone composition is component (f) described above. However, a tin (iv) catalyst may optionally be provided in the composition if desired. When present, the tin (iv) catalyst may be any suitable tin (iv)-based condensation cure catalyst. Examples of suitable tin (iv)-based catalysts include tin trifluoromethanesulfonate, dialkyltin compounds selected from dimethyltin di-2-ethylhexanoate, dimethyltin dilaurate, di-n-butyltin diacetate (DBTDA), di-n-butyltin di-2-ethylhexanoate, dimethyltin dineodecanoate (DMTDN), dioctyltin dineodecanoate (DOTDN), di-n-butyltin dioctoate, di-n-butyltin di-2,2-dimethyloctoate, di-n-butyltin octoate, dilaurate Di-n-butyltin (DBTDL), di-n-butyltin distearate, di-n-butyltin dimaleate, di-n-butyltin dioleate, di-2-ethylhexanoate di-n-octyltin, di-2,2-dimethyloctanoate di-n-octyltin, di-n-octyltin dimaleate, di-n-octyltin dilaurate (DOTDL), di-n-butyltin oxide, tri-octanoic acid methyl phenyl tin, tin butyrate, tri-2-ethylhexanoic acid butyltin, tin naphthenate, tri-ceroic acid isobutyltin, tin octanoate, triethyltin tartrate and di-n-octyltin oxide. When present, the condensation catalyst based on tin (IV) can be present in an amount of 0.001% by weight to 0.1% by weight (wt.%) (including end values) of the composition. It is found that, although not essential, if necessary, a small amount of tin (IV) catalyst can be used to accelerate curing, such as tack-free time (TFT). That is, in one embodiment, there is no tin (IV) catalyst in the composition.

[0158] UV and / or light stabilizers

[0159] For purposes of example, the UV and / or light stabilizer may include benzotriazole, ultraviolet light absorber and / or hindered amine light stabilizer (HALS), such as HALS from Ciba Specialty Chemicals Inc. Product series.

[0160] Biocides

[0161] If desired, a biocide may be additionally utilized in the composition. The term "biocide" is intended to include bactericides, fungicides, algaecides, and the like. For purposes of illustration, suitable examples of useful biocides that may be utilized in the compositions described herein include:

[0162] Carbamates, such as methyl-N-benzimidazol-2-ylcarbamate (carbendazim) and other suitable carbamates; 10,10'-oxybisphenoxane; 2-(4-thiazolyl)-benzimidazole; N-(fluorodichloromethylthio)phthalimide, diiodomethyl-p-tolylsulfone, if appropriate in combination with UV stabilizers, such as 2,6-di(tert-butyl)-p-cresol, 3-iodo-2-propynylbutylcarbamate (IPBC), zinc 2-pyridinethiol 1-oxide, triazole compounds and isothiazolinones, such as 4,5-dichloro-2-(n-octyl)-4-isothiazolin-3-one (DCOIT), 2-(n-octyl)-4-isothiazolin-3-one (OIT) and n-butyl-1,2-benzisothiazolin-3-one (BBIT). Other biocides may include, for example, zinc pyrithione, 1-(4-chlorophenyl)-4,4-dimethyl-3-(1,2,4-triazol-1-ylmethyl)pentan-3-ol, and / or 1-[[2-(2,4-dichlorophenyl)-4-propyl-1,3-dioxolan-2-yl]methyl]-1H-1,2,4-triazole.

[0163] The fungicide and / or biocide may suitably be present in an amount of from 0% to 0.3% by weight of the composition and may if desired be present in encapsulated form such as described in EP2106418.

[0164] Thus, the one-part thermal porous surface condensation-curable silicone composition described herein suitable for application to a porous substrate at a temperature of at least 40° C. may comprise

[0165] (a) an organopolysiloxane polymer having at least two hydroxyl groups or hydrolyzable groups per molecule of the following formula:

[0166] X 3-n R n Si-Z-(R 1 y SiO (4-y) / 2 ) z –SiR 1 2-Z-Si-R n X 3-n (1)

[0167] wherein each X is independently a hydroxyl group or an alkoxy group, each R is an alkyl, alkenyl or aryl group, and each R 1 is an X group, an alkyl group, an alkenyl group or an aryl group and Z is a divalent organic group;

[0168] n is 0 or 1, y is 0, 1 or 2, and preferentially 2, and z is an integer such that the organopolysiloxane polymer has a viscosity of 10,000 to 150,000 mPa.s at 25°C, alternatively 30,000 to 140,000 mPa.s at 25°C according to Corporate test method CTM 0050, which is publicly available and based on ASTM D1084-16 method B, using a Brkfield HBDV-III Ultra rheometer equipped with cone-plate geometry, using spindle 52, the organopolysiloxane polymer being in an amount of 30 to 90 wt % of the composition, alternatively 35 to 75 wt %, alternatively 35 to 60 wt % of the composition;

[0169] (b) one or more reinforcing fillers selected from the group consisting of

[0170] % to 35% by weight of the composition, alternatively 5% to 30% by weight of the composition, alternatively 5% to 25% by weight of the composition, and wherein when the selected filler is precipitated calcium carbonate, the composition will tend to include a greater % by weight of the composition, for example 25% to 60% by weight of the composition, alternatively 30% to 60% by weight of the composition, alternatively 35% to 55% by weight of the composition;

[0171] (c) a silane compound having two hydrolyzable groups per molecule of the following formula:

[0172] R 3 2-Si-R 4 2

[0173] Each group R 3 may be the same or different and are hydrolyzable groups selected from alkoxy or acetoxy groups, and each R 4The groups are the same or different and independently represent the presence of an alkyl group, alkenyl group, alkynyl group, aryl group or fluorinated alkyl group having 1 to 10 carbon atoms; the amount of the silane compound is 1% to 10% by weight of the composition, alternatively 1.25% to 7.5% by weight of the composition, alternatively 1.5% to 4.0% by weight of the composition;

[0174] (d) tetra-n-propoxysilane in an amount of 0.40 wt % to 3.5 wt % of the composition,

[0175] Alternatively 0.40% to 3.0% by weight of the composition, alternatively 0.40% to 2.5% by weight of the composition, alternatively 0.40% to 2.5% by weight of the composition, alternatively 0.50% to 2.0% by weight of the composition;

[0176] (e) a silicon-containing compound having three or more hydrolyzable groups per molecule, selected from

[0177] (e)(a') 1,3,5-Tris(trialkoxysilylalkyl)isocyanurate

[0178] (e) (b') Siloxane oligomers of the following structure

[0179] Si-((O-Si(CH3)2) n’ -(R 7 -Si(CH3)2-O-Si(CH3)2) z’ -R 7 -Si(OR 8 )3)4;

[0180] Each R 7 Can be the same or different and can be the same as R 5 The same and each R 8 Can be the same or different and can be the same as R 6 are the same, n' is an integer and z' is 0 or 1; or

[0181] (e) (c') Siloxane oligomers of the following structures

[0182] R 9 -Si-((O-Si(CH3)2) n’ -(R 7 -Si(CH3)2-O-Si(CH3)2) z’ -R 7 -Si(OR 8 )3)3

[0183] The same R 7 , R 8n' and z' are as defined above, and R 9 Can be used with R 8 the same; present in an amount of 0.1% to 5% by weight of the composition, present in an amount of 0.1% to 4% by weight of the composition, alternatively present in an amount of 0.1% to 2.5% by weight of the composition, alternatively present in an amount of 0.1% to 1.5% by weight of the composition, alternatively present in an amount of 0.1% to 1.0% by weight of the composition; and

[0184] (f) a catalyst comprising a titanate-based compound, a zirconate-based compound, or a mixture thereof in an amount of 0.05 to 1.5 wt % of the composition, alternatively 0.05 to 1.25 wt % of the composition, alternatively 0.1 to 1.0 wt % of the composition, alternatively 0.1 to 0.75 wt % of the composition.

[0185] The one-part thermal porous surface condensation-curable silicone composition may include any combination of the above-mentioned substances, provided that the total composition of components (a) to (f) and any other optional components contained in the composition has a value of 100% by weight of the composition. It should be understood that component (d) and component (e) are different. In addition, as previously described, components (c) + (d) + (e) are cumulatively present in the one-part thermal porous surface condensation-curable silicone composition in the range of 1.5% to 18.5% by weight of the composition. Alternatively, components (c) + (d) + (e) may be cumulatively present in the range of 1.5% to 10% by weight of the composition; alternatively, components (c) + (d) + (e) may be cumulatively present in the range of 2.0% to 7.5% by weight of the composition; alternatively, components (c) + (d) + (e) may be cumulatively present in the range of 2.5% to 7.5% by weight of the composition.

[0186] Also provided is a method for sealing a thermally porous substrate, wherein the substrate is at a temperature of at least 40° C., the method comprising the steps of:

[0187] (i) applying a one-part thermoporous surface condensation-curable silicone composition as described above to a thermoporous substrate at a temperature of at least 40° C.; and

[0188] (ii) curing the composition.

[0189] Alternatively, in order to obtain a silicone sealant bonded to the surface of a thermal porous substrate, a method for bonding a silicone sealant to a thermal porous substrate at a temperature of at least 40°C is provided, comprising the following steps: preparing a one-part thermal porous surface condensation-curable silicone composition as described above, contacting the surface of the thermal porous substrate with the one-part thermal porous surface condensation-curable silicone composition at a temperature of at least 40°C, and curing the one-part thermal porous surface condensation-curable silicone composition.

[0190] The one-part thermal porous surface condensation-curable silicone composition as described above can be prepared by mixing all the ingredients together. Preferably, once mixed, the composition is sealed in one or more moisture-proof containers and stored unless used immediately. In one embodiment, fillers (b) and / or pigments are first mixed into polymer (a) when present, optionally, if desired, in combination with a hydrophobic treatment agent, so that the filler and optional pigment can be hydrophobically treated in situ during mixing into the polymer.

[0191] Once the filler is thoroughly mixed into the polymer (and, if necessary, has been hydrophobized), the remaining components are added in any suitable order to prepare the complete composition.

[0192] For example, in one approach, a process for preparing a one-part thermally porous surface condensation-curable silicone composition, when an optional pigment is present, may include the following steps:

[0193] 1) If necessary, the one or each reinforcing filler (b) is placed under vacuum for a predetermined time.

[0194] and any non-reinforcing filler (when present) and, if desired, a hydrophobic filler treating agent, gradually added to polymer (a) for a predetermined period of time; to form a polymer matrix;

[0195] 2) premixing components (c), (d), (e) and (f) to form premix 1;

[0196] 3) If deemed necessary, then add premix 1 to the polymer base under vacuum and mix into the base;

[0197] 4) Finally the mixture is cooled to below 40°C, the vacuum is released and the final composition is packaged if for storage.

[0198] When an optional pigment is to be used, the pigment may be introduced before or simultaneously with the filler, thereby producing a colored polymer base after completion of step 1 above. Optional ingredients such as tackifiers may also be added to premix 1. However, when an optional tin catalyst is to be included in the composition, a second premix may be prepared containing, for example, optional ingredients such as tackifiers and optional tin (iv) catalysts. When two premixes are desired, they may be separated so that portions of components (d), (e), (f), and (c) are mixed together in one premix, for example premix 1a and the remainder of component (c), the optional tackifier, and the tin (iv) catalyst are mixed together in a second premix (premix 2), and the two premixes may be introduced and mixed into the composition in any order, for example premix 1a may be added first, mixed in, and premix 2 may be added and mixed in to complete the composition.

[0199] For one-part room temperature vulcanizable (RTV) silicone compositions containing alkoxy terminated polymers (a) and titanate / zirconate catalysts (f), bubbling is a common problem on stone, marble, brick, concrete, cement and other cementitious substrates, especially stone substrates, during the summer months, especially after storage. When a standard one-part room temperature vulcanizable (RTV) silicone composition having an alkoxy terminated polymer and a titanate and / or zirconate catalyst is applied to a porous surface at a temperature below 40°C, some bubbles are formed. However, when the substrate is at a temperature of 40°C or higher, typically due to direct sunlight, the generation of bubbles is much more pronounced and is therefore more easily observed. Without being bound by current theory, it is believed that bubbling may be caused by the generation of alcohol (particularly methanol) during the curing process at elevated temperatures, with the porous nature of the substrate acting as a form of accelerator, with the pores of the porous substrate acting as nucleation sites for bubble formation which are then trapped within the bulk of the sealant during cure, not least because of the process by which such compositions cure, i.e., the initial formation of a skin to prevent the escape of bubbles will be accelerated (particularly at elevated temperatures) compared to when the sealant is cured at or near room temperature, thereby causing the skin to form more quickly.

[0200] However, the one-part hot porous surface condensation-curable silicone composition as described in the present disclosure may be applied to a hot porous substrate at a temperature of at least 40°C by any suitable means, such as by extrusion, coating, injection, knife coating and rolling, which generally depends on the viscosity and the ability to flow on the substrate surface. Regardless of the means of application, it was found that no bubbles or relatively much fewer bubbles were formed at the interface between the porous substrate surface and the applied sealant when compared to standard one-part room temperature vulcanizable (RTV) silicone compositions. The reduction in the number and size of bubbles in the cured silicone sealant compared to standard RTV silicone sealants is significant and therefore has significant benefits to the construction industry in hot countries where the substrate often reaches temperatures in excess of 40°C during the hottest part of the day due to heat from the sun, etc., as significant bubble formation with respect to standard sealants has proven to be a major problem for the construction industry as it results in surface blistering between the cured / cured sealant and the substrate surface, resulting in poor adhesion therebetween. These bubbles are unacceptable and can increase the volume of the cured product by as much as two or three times compared to a product that has not been cured on a thermally porous substrate.

[0201] An additional advantage of the one-part thermoporous surface condensation-curable silicone composition of the present invention is that it allows the user to have increased working time compared to standard sealant compositions that tend to cure very quickly at the relevant temperatures because after the one-part thermoporous surface condensation-curable silicone composition is applied to the thermoporous substrate, it is exposed to atmospheric moisture, causing it to cure and adhere to the initial thermoporous substrate surface.

[0202] Also provided herein is an elastomeric sealant material, which is a cured product of the one-part thermal porous surface condensation-curable silicone composition as described above. Alternatively, a sealant that bonds to a thermal porous substrate at a temperature of at least 40°C is provided, which is obtained or can be obtained by preparing the one-part thermal porous surface condensation-curable silicone composition as described above, contacting the surface of the thermal porous substrate with the one-part thermal porous surface condensation-curable silicone composition at a temperature of at least 40°C, and curing the one-part thermal porous surface condensation-curable silicone composition.

[0203] The resulting elastomeric sealant material not only adheres to thermally porous substrates with significantly reduced levels of trapped bubbles, but it also exhibits a high migration capability of 50% passing ASTM C920, excellent adhesion on various substrates according to ASTM C794, and very good non-staining performance considering it passes ASTM C1248.

[0204] Thus, the one-part thermal porous surface condensation-curable silicone compositions herein can be further controlled to design low modulus one-part thermal porous surface condensation-curable silicone compositions in view of the high mobility. The low modulus silicone sealant compositions are preferably "sprayable", i.e., they have suitable extrusion capabilities and given that the resulting sealant imparts to the post-cured sealant material greater than 25%, and indeed in one exceptional case greater than 50%, mobility as measured according to ASTM C920 50%.

[0205] Thus, the one-part thermal porous surface condensation-curable silicone composition as described above suitable for application to a porous substrate at a temperature of at least 40° C. may be a sprayable sealant composition for:

[0206] (i) Space / gap filling applications;

[0207] (ii) Sealing applications, such as sealing the edges of lap joints in structural membranes; or

[0208] (iii) anti-fouling and weather-resistant sealants;

[0209] (iv) adhering at least two substrates together; and / or

[0210] (v) A layer laminated between two substrates to produce a laminate of the first substrate, the sealant product and the second substrate.

[0211] In the case of (v) above, when used as a layer in a laminate, the resulting laminate structure is not limited to these three layers. Additional cured sealant layers and substrate layers may be applied. The layer of sprayable sealant composition in the laminate may be continuous or discontinuous.

[0212] In the case of a one-part thermally porous surface condensation-curable silicone composition as described above, there is provided a method for filling a space between two substrates to create a seal between the two substrates, the method comprising:

[0213] a") providing a one-part thermally porous surface condensation-curable silicone composition as described above, and

[0214] b") applying a one-part thermal porous surface condensation-curable silicone composition to a first substrate at a temperature of at least 40°C and contacting a second substrate with the silicone composition applied to the first substrate, wherein either or both of the substrates are porous substrates, or

[0215] c") filling a space formed by the arrangement of a first substrate and a second substrate with a one-part thermal porous surface condensation-curable silicone composition at a temperature of at least 40°C, wherein one or both of the substrates are porous substrates, and

[0216] d") curing the silicone composition.

[0217] The one-part thermal porous surface condensation-curable silicone composition as described above, suitable for application to porous substrates at temperatures of at least 40°C, can be applied to any suitable substrate, but is contemplated to be particularly designed for application to substrates such as stone, marble, brick, concrete, cement and other cementitious substrates, combinations thereof, and in combination with other non-porous building materials such as metals (e.g., aluminum and steel) and glass, which can reach temperatures of at least 40°C during the hottest hours of summer in hot countries, as a stain-resistant and weather-resistant sealant material for construction and similar applications.

[0218] Thus, the one-part thermal porous surface condensation-curable silicone composition as described above can provide a silicone sealant of the low modulus type that can have high mobility. In addition, the composition herein is clear, i.e. transparent and / or translucent, and non-staining (clean) on building substrates (such as granite, limestone, marble, masonry and glass) that can reach temperatures of at least 40°C during the hottest hours of summer in hot countries.

[0219] When designed to a low modulus as described herein, the low modulus properties of the silicone elastomer produced upon cure of the one-part thermal porous surface condensation-curable silicone composition renders the elastomer effective in sealed joints that may be subject to movement for any reason because lower forces are generated in the body of the cured sealant compared to other cured sealants (having standard or high modulus) and these forces are transmitted through the sealant to the substrate / sealant interface due to expansion or contraction of the joint, thereby enabling the cured sealant to accommodate greater joint movement without failing cohesively or interfacially (adhesively) or causing substrate failure.

[0220] Also provided is the use of the aforementioned one-part thermal porous surface condensation-curable silicone composition as a sealant suitable for application at elevated temperatures (i.e., greater than 40° C.) to porous substrates such as stone, marble, brick, concrete, cement and other cementitious substrates, combinations thereof, and combinations with other non-porous building materials in the fields of building facades, insulating glass, window construction and construction in hot countries. The porous substrate can be particularly preferably used as a weather seal on a stone facade. Example

[0221] A series of examples are now provided.

[0222] Unless otherwise noted, all viscosity measurements are obtained at 25° C. Unless otherwise noted, all viscosities in the examples are measured according to corporate test method CTM 0050, which is publicly available and based on ASTM D1084-16 Method B, using a Brookfield HBDV-III Ultra Rheometer equipped with cone-plate geometry, using spindle 52.

[0223] Blistering typically occurs when alkoxy sealant compositions are applied to porous substrates (e.g., stone, marble, brick, concrete, cement and other cementitious substrates, etc.) during the summer (hot) season in countries where temperatures for most of the working day would subject exterior building surfaces to temperatures of at least 40°C. Blistering occurs particularly in sealant compositions that have been stored prior to use. To simulate such conditions, the stone test substrates were heated in an oven for at least 30 minutes prior to application of the sealant, and all stone test samples were tested when their surface temperature was above 40°C, typically 50°C, unless otherwise stated.

[0224] The compositions of Comparative Example 1 (C1) and Examples 1 to 4 (Ex1 to Ex. 4) are provided in Table 1 below.

[0225] Table 1: Formulations in % by weight of Comparative Example (C1) and Examples of the present invention (Ex. 1 to 4)

[0226] Material C.1 Ex.1 Ex.2 Ex.3 Ex.4 polymer 44.97 44.97 44.92 44.67 44.22 Precipitated Calcium Carbonate (PCC) Filler 32 32 32 32 32 Heavy calcium carbonate (GCC) filler 18 18 18 18 18 Vinylmethyldimethoxysilane (VMDM) 3.5 2 2.8 3.2 3.8 Catalyst 1 0.87 0.87 0.87 0.87 0.87 Dioctyl bis(lauroyloxy)tin(DOTDL) 0.05 Tris(3-trimethoxysilylpropyl)isocyanurate 0.5 0.5 0.5 0.5 0.5 Tetrapropoxysilane (TPOS) 1.5 0.7 0.6 0.45 3-(2-Aminoethyl)aminopropyltrimethoxysilane 0.16 0.16 0.16 0.16 0.16 total 100 100 100 100 100

[0227] In Table 1:

[0228] polymer : The polymer is a (MeO)3Si-CH2-CH2-terminated polydimethylsiloxane polymer having a viscosity of about 65,000 MPa.s at 25°C;

[0229] Precipitated Calcium Carbonate (PCC) Filler PCC is a product of Shiraishi Kogyo Kaisha, Ltd. under the trade name Hakuenka TM Ultrafine precipitated calcium carbonate coated with fatty acids sold by CCR-S;

[0230] Heavy Calcium Carbonate (GCC) :GCC is Omyacarb TM 5T, which is a fine coated ground calcium carbonate (GCC) available from OMYA AG; and

[0231] Catalyst 1 :Catalyst 1 is Tyzor TMPITA SM, which is an 80:20 wt % mixture of diisopropoxy-bisethylacetoacetate titanate and methyltrimethoxysilane, is commercially available from Dorf Ketal Speciality Catalysts, LLC, Stafford, Texas, USA.

[0232] Each composition in Table 1 was prepared using the following procedure:

[0233] The Examples and Comparative Examples were prepared based on 5 kg samples using a 10 liter Turello mixer as follows:

[0234] 1) First, the polymer and pigment were introduced into a mixer and mixed together at 400 rpm for 5 minutes;

[0235] 2) PCC and GCC fillers were then gradually introduced into the mixer at an increased mixing speed of 800 rpm under full vacuum for 8 minutes, after which the mixture in the mixer was scraped down and the mixture was mixed for an additional 7 minutes to form a pigmented silicone polymer base;

[0236] 3) separately prepare premix 1 by mixing tris(3-trimethoxysilylpropyl)isocyanurate, TPOS and VMDM together with a titanate catalyst;

[0237] 3a) In the case of Example (2), when a tin catalyst is present, the VMDM is divided between the two premixes Premix 1 and Premix 2 as described above, wherein the remaining VMDM is mixed with 3-(2-aminoethyl)-aminopropyltriethoxysilane and DOTDL to form a second premix (Premix 2); when a tin catalyst is not present but an adhesion promoter is present, the adhesion promoter is introduced into Premix 1;

[0238] 4) Premix 1 was then added to the pigmented silicone polymer base obtained from step 2 and mixed with it for another 5 minutes at 400 rpm before adding premix 2 (if necessary), after which the mixing was increased to 800 rpm and continued to mix for 20 minutes under a vacuum of -70 kPa;

[0239] 5) The mixing was then reduced and the vacuum increased to -80 kPa for 5 minutes, after which the final mixture was introduced into a cartridge for storage once the mixture had cooled sufficiently.

[0240] Samples of the sealant compositions depicted in Table 1 above were aged in a cartridge at 50°C for two weeks before they were packaged in the cartridge and then applied to a granite substrate sample that was at about 50°C when the sealant was applied. The aging cycle was selected as an accelerated test to simulate the shelf life of the sealant. Bubbling issues primarily occurred when the sealant was stored for more than 5-6 months. All fresh samples showed no significant bubbling issues; therefore, the aged samples were used to validate the mitigation method or composition.

[0241] The results are provided in Table 2 below.

[0242] Table 2: Blistering status check: wet sealant aged at 50°C for 2 weeks, then applied at about 50°C on a 50°C granite On rock substrate .

[0243] General performance C.1 Ex.1 Ex.2 Ex.3 Ex.4 Description of the bubbling state Many bubbles No bubbles No bubbles No bubbles Very few bubbles Scoring of bubbling status 5 1 1 1 1.5

[0244] The amount of bubbles present in the cured sealant was visually assessed on a scale of 1 (no bubbling or minimal bubbling observed) to 5, where significant bubbling was observed, which resulted in poor adhesion between the granite substrate and the cured sealant. The scoring criteria for bubbling status were as follows:

[0245] 1 = No bubbling observed

[0246] 2 = Very small bubbles, no effect on adhesion

[0247] 3 = Some bubbling, may have a negative impact on adhesion

[0248] 4 = Obvious bubbling observed, negatively affecting adhesion

[0249] 5 = Very significant bubbling observed, almost no adhesion (easily peeled off by hand)

[0250] It was found that in the case of C.1, numerous bubbles were observed and subsequently it was found that when such high levels of visually apparent bubbles were present, it had a significant effect on the adhesion of the cured sealant to the granite substrate, with poor adhesion being observed. Ex. 1, 2 and 3 had excellent results with essentially no bubbles observed and good adhesion between the granite substrate and the cured sealant. Ex. 4 (which had slightly less TPO present) did have a small number of apparent bubbles, but they were minimal and their presence did not appear to have any effect on the adhesion between the substrate and the cured sealant.

[0251] The unaged physical properties of the comparative examples and four examples were also evaluated. Each sealant test piece, etc., was prepared according to the relevant test method and tested to evaluate various physical properties of each of C.1 and Ex. 1 to 4. The results are provided in Table 3a, and the methods used are provided below.

[0252] Table 3a: Unaged physical properties of comparative example (C.1) and examples of the present invention (Ex. 1 to 4)

[0253] General performance C.1 Ex.1 Ex.2 Ex.3 Ex.4 Tack-free time (TFT) min 29 170 31 58 50 Extrusion rate (g / min) 146 91 100 135 144 Cure Depth (CID) (1 day), mm 1.44 2.08 1.92 1.88 1.6 Tensile strength(MPa) 2.53 2.18 2.37 2.27 2.46 Elongation at break (%) 716 407 551 594 644 Shore A Hardness 32.45 41.30 41.10 37.95 38

[0254] The test method used to generate the results in Table 2a is provided below:

[0255] Tack Free Time (TFT) was measured by polyethylene contact according to Dow's corporate test method (CTM) 0095, and the results plotted are measured in minutes.

[0256] Extrusion rate is measured according to Dow's CTM 0364. It is designed to determine the rate at which a material is extruded through a standard nozzle at a specified pressure and is based on MIL (Military Specification) MIL-S-8802 D. Results are provided in g / min.

[0257] Cure Depth (CID) is measured in accordance with Dow's CTM 0663 and measures the depth of cure of a sample by measuring how deep below the surface the cured material hardens in a specified time. Results are taken after 1 day and are provided in mm.

[0258] Tensile strength was measured according to Dow's CTM 0137A based on ASTM D 412 and using Die C. Results are provided in MPa.

[0259] Elongation at break is measured according to Dow's CTM 0137A based on ASTM D 412 and using Die C. Results are provided in %.

[0260] Shore A hardness is measured according to Dow's CTM 099 based on ASTM D 2240.

[0261] All of the above corporate test (CTM) methods are publicly available upon request from Dow Silicones Corporation.

[0262] It was found that in each case the properties of the sealants prepared using the compositions defined in the table were satisfactory. However, it can be seen that increased TPS levels lead to slower TFTs. While this is not a problem in most cases, it was found that TFTs can be faster if a small amount of tin (iv) catalyst is added to the composition.

[0263] The above samples of C.1 and Ex.3 were then aged to evaluate the physical properties of the sealant materials after aging. Aging was performed at 50°C for more than 2 weeks and at 50°C for more than 4 weeks. The results are depicted in Table 3b and Table 3c, respectively.

[0264] Table 3b: Physical properties of C.1 and Ex.3 after aging at 50°C for 2 weeks

[0265] C.1 Ex.3 Tack-free time (TFT) min 60 58 Extrusion rate (g / min) 152 135 Tensile strength(MPa) 1.72 2.14 Elongation at break (%) 998 860 Shore A Hardness 21.65 31.65

[0266] Table 3c: Physical properties of C.1 and Ex.3 after aging at 50°C for 4 weeks

[0267] C.1 Ex.3 Tack-free time (TFT) min 67 55 Extrusion rate (g / min) 165.5 151 Tensile strength(MPa) 1.08 1.97 Elongation at break (%) 998 751 Shore A Hardness 19.1 30.60

[0268] Compared with C.1 and Ex.3, it shows better aging performance.

[0269] C.1 and Ex.3 were also compared against a series of tests from the Chinese National Standard GB / T 23261-2009—Building sealants for stone, and the results are depicted in Table 4 below.

[0270] Table 4: According to Chinese national standard GB / T Physical properties test of 23261-2009

[0271]

[0272] NF = No Failure, WI = Water Immersion.

[0273] Elastic recovery testing was performed on samples cured at room temperature for 28 days. The samples were stretched to 100% elongation and then released and the elastic recovery determined.

[0274] In the first adhesion test, an Instrn tensile tester (if the model is known) was used to determine whether the sample suffered cohesive failure (CF) or adhesive failure (AF) when extended to 100% after curing for 28 days under standard conditions (23°C and 50% relative humidity). In the third adhesion test, the sample was cured for 28 days and then placed in water for 4 days before being removed from the water and placed at room temperature under standard conditions for 24 hours, and then subjected to a tensile strength test using an Instrn tensile tester to determine whether the sample suffered any cohesive failure or adhesive failure.

[0275] Adhesion failure (AF) is the interfacial bonding failure between the adhesive and the adherend. Cohesive failure occurs when the fracture allows the adhesive layer to remain on both surfaces. Therefore, in Table 4, cohesive failure (CF) is observed when the sealant itself fractures without separating from the substrate. In some cases, mixed failure modes can be observed; that is, some areas peel off (i.e., AF), while some areas remain covered by the coating (i.e., CF). In this case, the surface portion shows CF (% CF).

[0276] A more detailed evaluation of the adhesion capabilities of C.1 and Ex.3 was conducted in accordance with ASTM C794 relative to several different substrates, and the results are provided in Table 5 below.

[0277] Table 5: Comparison of peel adhesion according to C.1 and Ex.3 of ASTM C794, results are given as % cohesive failure .

[0278]

[0279] The sealant composition according to the present disclosure exhibits good adhesion on various substrates.

[0280] In addition, the developed one-part alkoxy cleaning sealant also shows high mobility passing ASTM C920 50% and GB / T23261 50HM.

Claims

1. A one-part thermal porous surface condensation curable silicone composition suitable for application to a porous substrate at a temperature of at least 40°C, comprising the following components:- (a) an organopolysiloxane polymer having at least two hydroxyl groups or hydrolyzable groups per molecule of the following formula: X 3-n R n Si-Z-(R 1 y SiO (4-y) / 2 ) z -SiR 1 2-Z-Si-R n X 3-n (1) wherein each X is independently a hydroxyl group or an alkoxy group, each R is an alkyl, alkenyl or aryl group, and each R 1 is an X group, an alkyl group, an alkenyl group or an aryl group and Z is a divalent organic group; n is 0 or 1, y is 0, 1 or 2, and preferentially 2, and z is an integer such that the organopolysiloxane polymer has a viscosity of 10,000 to 150,000 mPa.s at 25°C, in an amount of 30 to 90% by weight of the composition; (b) one or more reinforcing fillers selected from precipitated silica, fumed silica or precipitated calcium carbonate; (c) a silane compound having two hydrolyzable groups per molecule of the following formula: R 3 2-Si-R 4 2 Each group R 3 can be the same or different and are hydrolyzable groups selected from alkoxy or acetoxy groups, and each R 4 The groups are the same or different and independently represent an alkyl group, an alkenyl group, an alkynyl group, an aryl group or a fluorinated alkyl group having 1 to 10 carbon atoms, and the silane compound (c) is present in the composition in an amount of 1% to 10% by weight of the composition; (d) tetra-n-propoxysilane is present in an amount from 0.40 wt % to 3.5 wt % of the composition; (e) a silicon-containing compound having three or more hydrolyzable groups per molecule selected from (e) (a') 1,3,5-tris(trialkoxysilylalkyl)isocyanurate (e) (b') Siloxane oligomers of the following structure Si-((O-Si(CH3)2) n’ -(R 7 -Si(CH3)2-O-Si(CH3)2) z’ -R 7 -Yes(OR 8 )3)4; Each R 7 Can be the same or different and can be 5 The same and each R 8 Can be the same or different and can be 6 are the same, n' is an integer and z' is 0 or 1; or (e) (c') Siloxane oligomers of the following structures R 9 -Yes-((O-Yes(CH3)2) n’ -(R 7 -Si(CH3)2-O-Si(CH3)2) z’ -R 7 -Yes(OR 8 )3)3 The same R 7 , R 8 n' and z' are as defined above and R 9 Can be used with R 8 Likewise, the silicon-containing compound (e) is present in the composition in an amount of 0.1 wt % to 5 wt % of the composition; as well as (f) A catalyst comprising a titanate-based compound, a zirconate-based compound or a mixture thereof.

2. The one-part thermal porous surface condensation-curable silicone composition according to claim 1, wherein each X and each R 3 Can be the same or different, but are alkoxy groups having 1 to 6 carbons.

3. A one part thermal porous surface condensation curable silicone composition according to any preceding claim wherein components (c) + (d) + (e) are present cumulatively in the range of 1.5 wt % to 10 wt % of the composition.

4. A one-part thermally porous surface condensation-curable silicone composition according to any preceding claim wherein component (e) is tris-(trimethoxysilylpropyl)isocyanurate.

5. The one-part thermal porous surface condensation-curable silicone composition according to any preceding claim, wherein component (b) is precipitated calcium carbonate, and wherein the one-part thermal porous surface condensation-curable silicone composition can additionally comprise a heavy calcium carbonate non-reinforcing filler.

6. A one-part thermally porous surface condensation-curable silicone composition according to any preceding claim which can additionally comprise an adhesion promoter and / or a pigment.

7. A one part thermoporous surface condensation curable silicone composition according to any preceding claim which is curable on a thermoporous surface at a temperature of at least 40°C with reduced bubble generation.

8. A method of applying a one-part thermoporous surface condensation-curable silicone composition to at least a thermoporous substrate at a temperature of at least 40°C, comprising the steps of: A one-part thermal porous surface condensation-curable silicone composition according to any one of claims 1 to 7 is prepared, a surface of a thermal porous substrate is contacted with the one-part thermal porous surface condensation-curable silicone composition at a temperature of at least 40°C, and the one-part thermal porous surface condensation-curable silicone composition is cured.

9. A method of applying a one-part thermoporous surface condensation-curable silicone composition to at least a thermoporous substrate at a temperature of at least 40°C, the method involving filling a space between two substrates to create a seal therebetween, the method comprising: a″) providing a one-part thermally porous surface condensation-curable silicone composition according to any one of claims 1 to 7, and b") applying the one-part thermal porous surface condensation-curable silicone composition to a first substrate at a temperature of at least 40°C and contacting a second substrate with the silicone composition applied to the first substrate, wherein either or both of the substrates are porous substrates, or c") filling a space formed by the arrangement of a first substrate and a second substrate with a one-part condensation-curable room temperature vulcanizable (RTV) silicone composition at a temperature of at least 40°C, wherein one or both of the substrates are porous substrates, and d") curing the silicone composition.

10. A method of applying a one-part thermoporous surface condensation-curable silicone composition according to claim 8 or 9 to at least a thermoporous substrate at a temperature of at least 40°C, wherein the substrate is stone, marble, brick, concrete, cement and other cementitious substrates, combinations thereof, and combinations with other non-porous building materials.

11. A sealant that bonds to a thermoporous substrate at a temperature of at least 40°C, the sealant being obtained or obtainable by: preparing a one-part thermoporous surface condensation-curable silicone composition according to any one of claims 1 to 7, contacting the surface of a thermoporous substrate with the one-part thermoporous surface condensation-curable silicone composition at a temperature of at least 40°C, and curing the one-part thermoporous surface condensation-curable silicone composition.

12. An elastomeric sealant material that adheres to a thermoporous substrate at a temperature of at least 40°C, the elastomeric sealant material being the cured product of the one-part thermoporous surface condensation-curable silicone composition according to any one of claims 1 to 7 and being free or substantially free of trapped bubbles.

13. A sealant according to claim 11 or 12 that bonds to a thermally porous substrate at a temperature of at least 40°C, wherein the substrate is stone, marble, brick, concrete, cement and other cementitious substrates.

14. Use of the one-part thermoporous surface condensation-curable silicone composition according to any one of claims 1 to 7 as a means of applying the one-part thermoporous surface condensation-curable silicone composition to the thermoporous substrate at a temperature of at least 40°C while minimizing the entrapment of bubbles in the resulting cured sealant after curing of the composition on the surface of the thermoporous substrate.

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