sealant composition

Abstract

A one-part, heat-porous, surface-condensation-curable silicone composition comprising an organopolysiloxane polymer having at least two alkoxy groups per molecule and a titanate- or zirconate-based catalyst, wherein the heat-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 for applying the one-part heat-porous, surface-condensation-curable silicone composition to a heat-porous substrate at a temperature of at least 40°C, and to the use of the one-part heat-porous, surface-condensation-curable silicone composition for treating a porous substrate at a temperature of at least 40°C.

Description

[0001] The present invention relates to a one-part, heat-porous, surface-condensation-curable silicone composition comprising an organopolysiloxane polymer having at least two alkoxy groups per molecule and a titanate- or zirconate-based catalyst, wherein the heat-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, heat-porous, surface-condensation-curable silicone composition to a heat-porous substrate at a temperature of at least 40°C, and to the use of the one-part, heat-porous, surface-condensation-curable silicone composition for treating 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 approximately 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 crosslinkers 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, and the like, are 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-cure (RTV) silicone compositions are typically used to create skin or diffusion-cure silicone elastomers. Alkoxytitanium compounds and / or alkoxyzirconium compounds (i.e., alkyl titanates) are well known to those skilled in the art as catalysts suitable for curing such one-part moisture-curable silicones. One-part condensation-cure silicone compositions are typically designed to minimize the presence of any water / moisture in the composition; that is, 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 layer at the composition / air interface after the sealant / encapsulant is applied to the substrate surface. After the skin layer is formed, the cure rate depends on the diffusion of moisture from the sealant / encapsulant-air interface to the inner side (or core) of the applied silicone composition layer, as well as the diffusion of condensation reaction byproducts / effluents from the inner side (or core) to the outer side (or surface) of the material, and the rate at which the cured skin layer gradually thickens from the outer side / surface to the inner side / core over time. Such single-part condensation-curing silicone compositions are applied in layers typically thinner than 15 mm. It is known that such compositions applied in layers thicker than 15 mm can result in uncured material deep within the material because moisture diffuses very slowly into very deep portions. The primary, if not the sole, source of moisture in these compositions is inorganic fillers, such as silica or calcium carbonate (when present). These fillers can be rendered anhydrous prior to intermixing with the other ingredients, or water / moisture can 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 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, applying one-part, condensation-curable silicone compositions to substrates such as stone, marble, brick, concrete, cement, and other cementitious substrates when the substrate surface is exposed to elevated temperatures, such as at least 40°C, is a problem for the construction industry. This is because, while one-part, condensation-curable silicone compositions are highly desirable for such purposes, given their minimal or no deleterious effects 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) can generate bubbles within the composition during the curing process when the substrate is hot. This often occurs on sunny days and in hot climates, when sunlight heats the substrate or associated building materials to temperatures often exceeding 40°C, particularly when the sealant being used has been stored for several months prior to use. These bubbles are unacceptable and can 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 wishing to be bound by current theory, it is believed that when an alkoxysilicone composition (typically used as a sealant) is applied to a hot porous substrate (especially a hydrophilic hot porous substrate) at a temperature of at least 40°C, increasing amounts of moisture / water vapor condense at the interface between the sealant and the porous substrate, driven by capillary action and the reactivity of moisture with the composition. This leads to increasing hydrolysis of the alkoxysilyl groups at the interface between the hot porous substrate at a temperature of at least 40°C, and thus, given the high temperature of the substrate, the production of an increased amount of alcohol, typically methanol. Bubbling is believed to be 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., the sealant composition). Consequently, bubbles are trapped during curing under these conditions, not simply because the process by which such compositions cure, i.e., the initial formation of a skin to prevent bubble escape (especially at elevated temperatures), results in faster skin formation compared to when the sealant cures at or near room temperature. This is particularly problematic when using such compositions, for example, as 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 percent (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, alkenyl group, alkynyl group, aryl group or 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 compared with R 5 Same and each R 8 Can be the same or different and can be compared with 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% to 5% by weight 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 percent of the composition is 100 weight percent. The one-part heat-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 during curing. The one-part heat-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 heat-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 the 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 thermally porous surface condensation-curable silicone composition to a thermally porous substrate at a temperature of at least 40° C., wherein the one-part thermally 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, alkenyl group, alkynyl group, aryl group or 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 compared with R 5 Same and each R 8 Can be the same or different and can be compared with 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% to 5% by weight 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 thermally porous substrate at a temperature of at least 40°C, comprising the steps of preparing a one-part thermally porous surface condensation-curable silicone composition as described above, contacting the surface of the thermally porous substrate with the one-part thermally porous surface condensation-curable silicone composition at a temperature of at least 40°C, and curing the one-part thermally porous surface condensation-curable silicone composition to obtain a silicone sealant bonded to the surface of the thermally porous substrate.

[0050] A sealant that bonds to a thermoporous substrate at a temperature of at least 40°C is obtained or is obtainable 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 percent (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, alkenyl group, alkynyl group, aryl group or 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 compared with R 5 Same and each R 8 Can be the same or different and can be compared with 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% to 5% by weight 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 organosilicon composition as described above, and

[0075] b") applying a one-part thermally 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, or

[0076] c") filling a space formed by the arrangement of a first substrate and a second substrate with a one-part thermally 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 of "comprising" is used in its broadest sense to mean and encompass the concepts of "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, amido, and cyano functional groups; sulfur atoms; and groups containing sulfur atoms such as mercapto groups.

[0081] A one-part, heat-porous, surface-condensation-curable silicone composition suitable for application to porous substrates at temperatures of at least 40°C is designed for bonding to the surface of a heat-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, heat-porous, surface-condensation-curable silicone composition can also be used to bond combinations of heat-porous surfaces together, as well as to other conventional building materials, such as glass and aluminum. The one-part, heat-porous, surface-condensation-curable silicone composition is contacted with the heat-porous surface by conventional means, such as extrusion, coating, injection, doctoring, and rolling. The one-part, heat-porous, surface-condensation-curable silicone composition is particularly intended for use 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 methods described herein are used, the reduction in bubbles at temperatures of 40°C or higher is significant. 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 into a silicone sealant bonded to the surface of the thermoporous 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 thermoporous substrate at a temperature of 40°C or higher. Therefore, it can be said that the one-part thermoporous surface condensation-curable silicone composition as described herein can be cured on a thermoporous surface (at least 40°C) while reducing bubble generation. Undesirable bubbles are primarily formed at the interface between the thermoporous substrate and the cured silicone surface. The ambient temperature for which the sealant composition is designed to cure is significantly higher than is typically 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 thermoporous surface condensation-curable silicone composition herein has an increased working time at temperatures 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 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 carbon atoms, exemplary alkoxy groups are methoxy, ethoxy, propoxy, isopropoxy, n-butoxy, tert-butoxy, isobutoxy, pentoxy, hexoxy, and 2-ethylhexyloxy; dialkoxy groups such as methoxymethoxy or ethoxymethoxy, and alkoxyaryloxy groups such as ethoxyphenoxy groups; alternatively, each X is an alkoxy group having one to six carbon atoms, alternatively one to four carbon atoms, 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 having 1 to 6 carbons, an alkenyl group having 2 to 6 carbons (such as vinyl, allyl and hexenyl groups) or an aryl group having 6 to 12 carbons; alternatively each R is an alkyl group having 1 to 6 carbons, or an aryl group having 6 to 12 carbons; alternatively each R is an alkyl group having 1 to 6 carbons, alternatively each R is an ethyl group or a methyl group. In one embodiment, R may include substituted aliphatic organic groups such as 3,3,3-trifluoropropyl groups, aminoalkyl groups, polyaminoalkyl groups and / or epoxyalkyl groups.

[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 carbon atoms, such as, for example, ethylene, propylene, butylene, pentylene, and / or hexylene groups; alternatively, an alkylene group having 2 to 6 carbon atoms, alternatively, an alkylene group having 2 to 5 carbon atoms. 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 by 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, and 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 diameter of 40 mm and a 1 s -1 The viscosity in the range of 2000 mPa.s to 30,000 mPa.s can be measured using a MCR 302 rheometer with a shear rate of 50 mm. -1 The shear rate can be measured using 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 1s -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 weight percent, alternatively 35 to 75 weight percent, alternatively 35 to 60 weight percent 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 intended 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 silicone macromolecule, or polymer or oligomer molecule. Synthetic polymers are always composed 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 silicone polymers can be determined by gel permeation chromatography (GPC) using polystyrene standards with an accuracy of about 10% to 15%.

[0092] This 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, with 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 determined, 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 the 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] The typical surface area of ​​silica reinforcing fillers is at least 50 m2 according to the BET method (ISO 9277:2010). 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 m³ / g as measured according to the BET method (ISO 9277:2010). 2 / g to 400m 2 / g, alternatively 100 m³ 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 the 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 facilitates wettability by component (a). These surface-modified fillers are preferably finely divided and free of agglomeration, and can be incorporated uniformly into the organosilicon polymer (a). This results in improved room-temperature mechanical properties of the uncured composition. The filler can be pretreated or treated in situ when mixed with component (a). A small amount of water can be added along with the silica treatment agent as a processing aid.

[0098] Depending on the filler selected, 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 contain 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 groups 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 thermally 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] Tetra-n-propoxysilane (d)

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

[0108] Si-(O-CH2CH2CH3)4

[0109] Surprisingly, it has been discovered that the addition of tetra-n-propoxysilane component (d) to one-part room temperature vulcanizable (RTV) silicone compositions 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 tetra-n-propoxysilane (component (d)) significantly and unexpectedly reduces the number and size of bubbles generated under such circumstances. It has been discovered that component (d) should be present in an amount of 0.40% to 3.5% by weight of the one-part thermal porous surface condensation-curable silicone composition, 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.

[0110] Component (e)

[0111] Component (e) of the one-part thermally 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, a 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 reacting chloroalkyltrialkoxysilanes with alkali metal cyanates in polar aprotic solvents. For example, preferred 1,3,5-tris(trialkoxysilylalkyl)isocyanurates (e)(a') are prepared by reacting chloropropyltrimethoxysilane with potassium cyanate in a suitable solvent such as dimethylformamide (DMF). This results in the production of a compound wherein each R 5 is a propylene group and each R 6 isocyanurate having 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 compared with R 5 Same and each R8 Can be the same or different and can be compared with 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, given 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 end 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 radical, 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. In one embodiment, each R 22 Same, and R 22 is isopropyl, a branched secondary or tertiary alkyl group, in particular tert-butyl.

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

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

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

[0133] Optional additives

[0134] Optional additives may be used if desired. These 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 different ways as described.

[0135] Non-reinforcing fillers

[0136] Non-reinforcing fillers that can 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 teffite, 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). Therefore, when component (b) reinforcing filler is precipitated calcium carbonate and non-reinforcing filler is also present in the composition, the total amount of precipitated calcium carbonate and non-reinforcing filler will still not exceed the upper limit 60 wt % of the composition. In one embodiment of the composition, when component (b) is precipitated calcium carbonate, the composition also includes ground calcium carbonate. When present, non-reinforcing filler can exist in an amount greater than zero wt % to 20 wt % of the composition.

[0141] pigment

[0142] The one-part thermal porous surface condensation-curable silicone composition as described herein may also contain 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 needed. Any suitable pigment may be utilized provided it is compatible 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 serve 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 orange, quinacridone pigments such as quinacridone magenta and quinacridone violet; organic reds including metallized and non-metallized azo reds and 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 perindigo 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 in microparticle form, 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%, alternatively 3%, alternatively 5% to 20% by weight of the composition.

[0147] Rheology modifiers

[0148] Rheology modifiers that can be incorporated into one-part thermally porous surface-condensation-curable silicone compositions include silicone organic copolymers, such as those described in EP 0802233 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 further comprise 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 comprise aminopropyltriethoxysilane or aminopropyltrimethoxysilane or may comprise:

[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 linear 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 R 10 In an alternative, 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-aminopropylmethyldiethoxysilane, N-(2-aminoethyl)-2-aminoethylmethyldimethoxysilane. 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-amino In some embodiments, the present invention includes 1-aminopropylmethylmethoxyethoxysilane, ...

[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) as 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 dimaleate, di-n-octyltin dilaurate (DOTDL), di-n-butyltin oxide, tri-octanedioic acid methyl phenyl tin, tin butyrate, tri-2-ethylhexanoic acid butyltin, tin naphthenate, isobutyltin triceroate, tin octoate, 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 has been found that, although not essential, if desired, 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, UV and / or light stabilizers may include benzotriazoles, ultraviolet light absorbers, and / or hindered amine light stabilizers (HALS), such as those from Ciba Specialty Chemicals Inc. product line.

[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′-oxobisphenoxane; 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 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, 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 %, 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 comprise a greater % by weight of the composition, for example, from 25% to 60% by weight of the composition, alternatively from 30% to 60% by weight of the composition, alternatively from 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 from 1% to 10% by weight of the composition, alternatively from 1.25% to 7.5% by weight of the composition, alternatively from 1.5% to 4.0% by weight of the composition;

[0174] (d) tetra-n-propoxysilane in an amount of 0.40% to 3.5% by weight 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 compared with R 5 Same and each R 8 Can be the same or different and can be compared with 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 from 0.1% to 5% by weight of the composition, present in an amount from 0.1% to 4% by weight of the composition, alternatively present in an amount from 0.1% to 2.5% by weight of the composition, alternatively present in an amount from 0.1% to 1.5% by weight of the composition, alternatively present in an amount from 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 from 0.05 to 1.5 weight percent of the composition, alternatively from 0.05 to 1.25 weight percent of the composition, alternatively from 0.1 to 1.0 weight percent of the composition, alternatively from 0.1 to 0.75 weight percent 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 ingredients included 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 a range of 1.5% to 18.5% by weight of the composition. Alternatively, components (c) + (d) + (e) may be cumulatively present in a range of 1.5% to 10% by weight of the composition; alternatively, components (c) + (d) + (e) may be cumulatively present in a range of 2.0% to 7.5% by weight of the composition; alternatively, components (c) + (d) + (e) may be cumulatively present in a 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 thermoporous substrate, a method for bonding a silicone sealant to a thermoporous substrate at a temperature of at least 40°C is provided, comprising the steps of 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.

[0190] The one-part thermal porous surface condensation-curable silicone composition 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, the filler (b) and / or pigment are first mixed into the polymer (a), if present, and optionally, combined with a hydrophobic treatment agent, if desired, so that the filler and, if applicable, the pigment can be hydrophobized 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 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 it is to be stored.

[0198] When optional pigments are to be used, the pigments may be introduced before or simultaneously with the fillers, 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 an optional tin (iv) catalyst. 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] Blistering is a common problem on stone, marble, brick, concrete, cement and other cementitious substrates, particularly stone substrates, during the summer months for one-part room temperature vulcanizable (RTV) silicone compositions containing an alkoxy-terminated polymer (a) and a titanate / zirconate catalyst (f), 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 temperatures below 40°C, some bubbles form. 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 therefore more easily observed. Without wishing to be 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, wherein the pores of the porous substrate act as nucleation sites for bubble formation which are then trapped within the bulk of the sealant during cure, not least because the process by which such compositions cure, i.e., the initial formation of a skin to prevent the escape of bubbles, particularly at elevated temperatures, will be accelerated 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 described in the present disclosure can be applied to hot porous substrates at temperatures of at least 40°C by any suitable means, such as extrusion, coating, injection, knife coating, and rolling, generally depending on the viscosity and ability to flow over the substrate surface. Regardless of the application method, it has been found that no bubbles, or relatively few bubbles, form 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 for the construction industry in hot countries, where substrates often reach temperatures exceeding 40°C during the hottest part of the day due to heat from the sun, etc., as significant bubble formation with standard sealants has proven to be a major problem in the construction industry, as it causes surface blistering between the cured / cured sealant and the substrate surface, resulting in poor adhesion between them. 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 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 original thermoporous substrate surface.

[0202] Also provided herein is an elastomeric sealant material, which is a cured product of the one-part, heat-porous, surface-condensation-curable silicone composition described above. Alternatively, a sealant that bonds to a heat-porous substrate at a temperature of at least 40°C is provided, the sealant being obtained or obtainable by preparing the one-part, heat-porous, surface-condensation-curable silicone composition described above, contacting the surface of the heat-porous substrate with the one-part, heat-porous, surface-condensation-curable silicone composition at a temperature of at least 40°C, and curing the one-part, heat-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 to various substrates according to ASTM C794, and very good non-staining performance considering it passes ASTM C1248.

[0204] Therefore, the one-part heat-porous surface condensation-curable silicone compositions herein can be further controlled to design low modulus one-part heat-porous surface condensation-curable silicone compositions with high mobility in mind. Low modulus silicone sealant compositions are preferably "sprayable," meaning they have suitable extrudability and impart to the post-cured sealant material a mobility greater than 25%, and in one exceptional case, greater than 50%, 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 can 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) antifouling and weatherproof 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 curing 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 thermally 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, or

[0215] c") filling a space formed by the arrangement of a first substrate and a second substrate with a one-part thermally 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 hot 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 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 in hot countries can reach temperatures of at least 40°C during the hottest parts of the summer, 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 is 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 part of the summer in hot countries.

[0219] When designed to be low modulus as described herein, the low modulus properties of the silicone elastomer produced upon curing of the one-part thermally porous surface condensation-curable silicone composition make 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, heat-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 building facades, insulating glazing, window construction, and construction in hot countries. The porous substrates are particularly preferably used as weather sealants on stone facades. Example

[0221] A series of examples are now provided.

[0222] Unless otherwise noted, all viscosity measurements were obtained at 25° C. Unless otherwise noted, all viscosities in the examples were 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] During the summer (hot) season in countries where temperatures for most of the working day would expose exterior building surfaces to temperatures of at least 40°C, blistering typically occurs when alkoxy sealant compositions are applied to porous substrates (e.g., stone, marble, brick, concrete, cement, and other cementitious substrates, etc.). Blistering occurs particularly with 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 sealant application, 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 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 Ground 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 Bis(lauroyloxy)dioctyltin (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 with 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] Ground 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 increasing 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 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 at 400 rpm for an additional 5 minutes before adding Premix 2 (if necessary), after which the mixing was increased to 800 rpm and continued under a vacuum of -70 kPa for 20 minutes;

[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 cartridges for storage once the mixture had cooled sufficiently.

[0240] Samples of the sealant compositions described in Table 1 above were aged in cartridges at 50°C for two weeks before being packaged in the cartridges and applied to granite substrate samples that were at approximately 50°C during sealant application. 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. None of the fresh samples showed significant bubbling issues; therefore, the aged samples were used to validate the mitigation methods or compositions.

[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 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 observed 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 noticeable 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 it was subsequently found that when such high levels of visually apparent bubbles were present, this had a significant impact 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 noticeable bubbles, but they were minimal and their presence did not appear to have any impact 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. Test pieces of each sealant, etc., were prepared according to the relevant test methods 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 will be extruded through a standard nozzle at a specified pressure and is based on MIL (Military Specification) MIL-S-8802D. The results are given in g / min.

[0257] Depth of cure (CID) is measured according to 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 reported in mm.

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

[0259] Elongation at break was measured according to Dow's CTM 0137A based on ASTM D 412 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 was seen that increasing TPS levels resulted in slower TFT. While this was not a problem in most cases, it was found that TFT could be faster if a small amount of tin (IV) catalyst was added to the composition.

[0263] The 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 plotted 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—Construction sealants for stone, and the results are depicted in Table 4 below.

[0270] Table 4: According to Chinese national standard GB / T Physical property testing 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 was determined.

[0274] In the first adhesion test, an Instrn tensile testing machine (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 testing machine to determine whether the sample suffered any cohesive failure or adhesive failure.

[0275] Adhesive failure (AF) is the failure of the interfacial bond between the adhesive and the adherend. Cohesive failure occurs when the fracture allows the adhesive layer to remain on both surfaces. Thus, in Table 4, cohesive failure (CF) is observed when the sealant itself fractures without separating from the substrate. In some cases, mixed failure modes may be observed; that is, some areas peel (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 performed according to 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 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 wt% 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 R4 group is the same or different and independently represents an alkyl group, alkenyl group, alkynyl group, aryl group or 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; (d) tetra-n-propoxysilane is present in an amount from 0.40% to 3.5% by weight 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 are the same or different and are divalent alkylene groups having 2 to 10 carbon atoms; and each R 8 are the same or different, are alkyl groups having 1 to 10 carbon atoms, n' is an integer and z' is 0 or 1; or (e) (c') Siloxane oligomers of the following structures R 9 -Si-((O-Si(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 Able to work 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 thermally porous surface condensation-curable silicone composition according to claim 1, wherein y is 2.

3. The one-part thermally 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.

4. The one-part thermally porous surface condensation-curable silicone composition of claim 1 or 2, wherein components (c) + (d) + (e) are present cumulatively in the range of 1.5 wt% to 10 wt% of the composition.

5. The one-part thermally porous surface condensation-curable silicone composition according to claim 1 or 2, wherein component (e) is tris-(trimethoxysilylpropyl)isocyanurate.

6. The one-part thermally porous surface condensation-curable silicone composition according to claim 1 or 2, wherein component (b) is precipitated calcium carbonate, and wherein the one-part thermally porous surface condensation-curable silicone composition can further comprise a heavy calcium carbonate non-reinforcing filler.

7. The one-part thermally porous surface condensation-curable silicone composition according to claim 1 or 2, which can further comprise an adhesion promoter and / or a pigment.

8. The one-part thermal porous surface condensation-curable silicone composition of claim 1 or 2, which is curable on a thermal porous surface at a temperature of at least 40°C with reduced bubble generation.

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., comprising the steps of: The one-part thermally porous surface condensation-curable silicone composition according to claim 1 is prepared, the surface of a thermally porous substrate is contacted with the one-part thermally porous surface condensation-curable silicone composition at a temperature of at least 40° C., and the one-part thermally porous surface condensation-curable silicone composition is cured.

10. 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 the two substrates to create a seal therebetween, the method comprising: a″) providing a one-part thermally porous surface condensation-curable silicone composition according to claim 1, and b") applying the one-part thermally 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 the first substrate and the 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, and d") curing the silicone composition.

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

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

13. A sealant that bonds to a thermoporous substrate at a temperature of at least 40°C, the sealant being obtained or obtainable by preparing the one-part thermoporous surface condensation-curable silicone composition according to claim 1, 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.

14. 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 the one-part thermally porous surface condensation-curable silicone composition of claim 1 and being free or substantially free of trapped bubbles.

15. A sealant according to claim 13 or 14 that bonds to a thermally porous substrate at a temperature of at least 40°C, wherein the substrate is stone, brick, concrete or cement.

16. A sealant according to claim 13 or 14 bonded to a thermally porous substrate at a temperature of at least 40°C, wherein the substrate is marble.

17. Use of the one-part thermoporous surface condensation-curable silicone composition according to claim 1 or 2 as a means for 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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