Bonding accelerant for moisture hardening type silicon resin as well as preparation method and application of bonding accelerant

Abstract

The invention provides an adhesion promoter for moisture-hardened silicon resin as well as a preparation method and application thereof, and belongs to the technical field of high polymer materials. The adhesion promoter disclosed by the invention comprises at least one of compounds with a structure as shown in a formula I: # imgabs0 #, wherein R1 is one of hydrogen, C1-C20 alkyl and aryl; r2 and R3 are respectively and independently methyl or ethyl; r4 is one of hydrogen, a hydroxyl group and a C1-C20 alkyl group; r5 is one of alkyl groups with 1 to 20 carbon atoms and aryl groups substituted by alkyl groups with 1 to 20 carbon atoms; in the formula I, X is 1, 3-methylene or 1, 6-ethylidene aminopropyl; and a is 0 or 1. The adhesion promoter disclosed by the invention is used in moisture-hardened silicon resin, and the weather resistance and water-resistant adhesion of the moisture-hardened silicon resin can be effectively improved.

Description

Technical Field

[0001] The present disclosure relates to the field of polymer technology, and in particular to an adhesion promoter for moisture-curing silicone resin, and a preparation method and application thereof. Background Art

[0002] Moisture-curing silicone resin compositions have excellent resistance to ultraviolet light, weathering, and high temperature and humidity. Compared with other types of sealants, their durability under harsh conditions is particularly outstanding, especially single-component room-temperature curing silicone sealants. Since the silicon-oxygen bonds of its main components are relatively stable, they have excellent aging resistance and are widely used in the fields of construction, automobiles, lighting, and electronics. Generally, silicone sealants have excellent weather resistance, but in long-term water immersion or high humidity environments, their water-immersion adhesion will gradually deteriorate or even fail, thereby losing their sealing and protective effects.

[0003] Moisture-curing silicone resin compositions generally have low surface energy and good wettability to most substrates. In addition, by using silane coupling agents such as aminosilane and / or epoxysilane as adhesion promoters, their adhesion to most substrates is further improved. However, aminosilane coupling agents containing active primary amine groups have a certain affinity for water vapor due to the activity of primary amines. In addition, primary amines are more susceptible to oxidation reactions such as ultraviolet rays and oxygen than secondary amine groups, thereby reducing the adhesion to the substrate. Therefore, it is necessary to continuously develop specific adhesion promoters to further improve the weather resistance and water-resistant adhesion of moisture-curing silicone resin compositions. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and provide an adhesion promoter for moisture-curing silicone resin and a preparation method and application thereof. The adhesion promoter is used in moisture-curing silicone resin and can effectively improve the weather resistance and water-resistant adhesion of moisture-curing silicone resin.

[0005] To achieve the above objectives, the technical solution adopted by the present disclosure is as follows: In a first aspect, an adhesion promoter for moisture-curing silicone resin is provided, wherein the adhesion promoter comprises at least one of the compounds having the structure shown in Formula I:

[0006]

[0007] Among them, R 1 is one of hydrogen, C1-C20 alkyl, and aryl; R 2 , R 3 Each is independently methyl or ethyl; R 4 is one of hydrogen, hydroxyl, and C1-C20 alkyl; R 5is one of C1-C20 alkyl and C1-C20 alkyl-substituted aryl; X is 1,3-methylene or 1,6-ethyleneaminopropyl; a is 0 or 1.

[0008] In some embodiments, the adhesion promoter includes at least one of the following compounds:

[0009]

[0010] In a second aspect, a method for preparing the adhesion promoter for moisture-curing silicone resin is provided, comprising the following steps:

[0011] Formaldehyde and aminosilane coupling agent are added to a solvent to dissolve, and then a catalyst is added, stirred evenly, and then salicylate is added, refluxed to react, and a reaction product is obtained; the reaction product is post-treated to obtain the adhesion promoter; wherein the molar ratio of salicylate: formaldehyde: aminosilane coupling agent is 1-3:1-3:1.

[0012] In some embodiments, the aminosilane coupling agent is at least one of aminopropyltrimethoxysilane, aminopropyltriethoxysilane, aminoethylaminopropyltrimethoxysilane, aminoethylaminopropyltriethoxysilane, aminopropylmethyldimethoxysilane, aminopropylmethyltriethoxysilane, aminoethylaminopropylmethyldimethoxysilane and aminoethylaminopropylmethyldiethoxysilane;

[0013] In some embodiments, the catalyst is an acid, and the acid is at least one of hydrochloric acid, sulfuric acid, and trifluoroacetic acid;

[0014] In some embodiments, the salicylate is phenyl salicylate and / or homosalate;

[0015] In some embodiments, the solvent is an alcohol solvent.

[0016] In a third aspect, a use of the adhesion promoter for moisture-curing silicone resin in moisture-curing silicone resin is provided.

[0017] In a fourth aspect, a moisture-curing silicone resin is provided, comprising the following components in parts by weight: 100 parts of polydimethylsiloxane, 1-10 parts of a cross-linking agent, 5-100 parts of a filler, 1-30 parts of a plasticizer, 0.01-5 parts of a catalyst, and 0.1-5 parts of an adhesion promoter as described in claim 1 or 2.

[0018] In some embodiments, the polydimethylsiloxane is at least one of α,ω-dihydroxy polydimethylsiloxane and methyldimethoxy-terminated polydimethylsiloxane;

[0019] In some embodiments, the viscosity of the polydimethylsiloxane at 25° C. is 1000-150000 mPa·s;

[0020] In some embodiments, the crosslinking agent is at least one of ketoxime silane and alkoxy silane;

[0021] In some embodiments, the filler is at least one of calcium carbonate, diatomaceous earth, quartz sand, and white carbon black.

[0022] In some embodiments, the plasticizer is at least one of mineral oil and dimethyl silicone oil;

[0023] In some embodiments, the catalyst is at least one of an organic tin catalyst and an organic titanium catalyst.

[0024] In some embodiments, the ketoxime silane is at least one of methyltributylacetoximosilane, vinyltributylacetoximosilane, and tetrabutylketoxime silane;

[0025] In some embodiments, the alkoxysilane is at least one of methyltrimethoxysilane, vinyltrimethoxysilane, propyltrimethoxysilane, methyl orthosilicate, and ethyl orthosilicate;

[0026] In some embodiments, the organotin catalyst is at least one of dibutyltin diacetate, dibutyltin dilaurate, dioctyltin dilaurate, stannous octoate, and dibutyltin acetylacetonate;

[0027] In some embodiments, the organic titanium catalyst is at least one of tetrabutyl titanate, tetra-tert-butyl titanate, diisopropoxy titanium diacetylacetonate, and diisopropoxy titanium diacetylacetate.

[0028] In some embodiments, the moisture-curing silicone resin further includes 0.01-5 parts by weight of a silane coupling agent, wherein the silane coupling agent is at least one of γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, 2-(3,4-epoxycyclohexane)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexane)ethyltriethoxysilane, γ-(glycidoxy)propylmethyltrimethoxysilane, and γ-(glycidoxy)propylmethyltriethoxysilane.

[0029] In a fifth aspect, a use of the moisture-curing silicone resin in a sealant is provided.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] (1) The present invention adds an adhesion promoter with a specific structure to a moisture-curing silicone resin. On the one hand, the salicylate structural unit in the adhesion promoter has an ultraviolet absorption function, which can improve the weather resistance of the moisture-curing silicone resin. On the other hand, compared with aminosilane, the adhesion promoter containing the salicylate structural unit can improve the compatibility of the moisture-curing silicone resin with a plastic substrate (such as PET), thereby improving the adhesion and water-resistant adhesion between the moisture-curing silicone resin and the plastic substrate. On the other hand, the addition of the ultraviolet absorber to the moisture-curing silicone resin can improve the moisture-curing silicone resin. The weather resistance of the moisture-curing silicone resin is poor, and there are problems such as poor solubility, easy migration and precipitation, which leads to a decrease in the weather resistance and water-resistant adhesion of the moisture-curing silicone resin; the silicon-containing group in the adhesion promoter of the present invention improves the compatibility of the ultraviolet absorber with the moisture-curing silicone resin, avoids the migration and precipitation of the ultraviolet absorber in the moisture-curing silicone resin, and improves the weather resistance and water-resistant adhesion of the moisture-curing silicone resin; fourthly, compared with the primary amine group in the aminosilane coupling agent, the amine in the adhesion promoter is a secondary amine group, which reduces the alkalinity of the adhesion promoter and improves the water-resistant adhesion of the moisture-curing silicone resin.

[0032] (2) The present invention uses bio-based salicylate to prepare an adhesion promoter, and the obtained adhesion promoter has certain renewability, sustainability and environmental protection.

[0033] (3) The preparation method of the adhesion promoter disclosed in the present invention is a one-step synthesis method with simple operation steps and easy industrial production. DETAILED DESCRIPTION

[0034] In order to facilitate understanding of the present disclosure, the present disclosure will be described more fully below. However, the present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present disclosure more thorough and comprehensive.

[0035] As used herein:

[0036] "Prepared from" is synonymous with "comprising." As used herein, the terms "comprising," "including," "having," "containing," or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises the listed elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

[0037] The conjunction "consisting of excludes any unspecified element, step, or component. If used in a claim, this phrase renders the claim closed-ended so that it does not include materials other than those described, except for conventional impurities associated therewith. When the phrase "consisting of" appears in a clause of the body of a claim rather than immediately following the subject matter, it limits only the elements described in that clause; other elements are not excluded from the claim as a whole.

[0038] When amount, concentration or other value or parameter is represented by range, preferred range or a series of upper preferred value and lower preferred value, this should be understood as specifically disclosing all ranges formed by any pairing of any range upper limit or preferred value and any range lower limit or preferred value, regardless of whether the range is disclosed separately. For example, when disclosing range "1-5", described range should be interpreted as including range "1-4", "1-3", "1-2", "1-2 and 4-5", "1-3 and 5" etc. When numerical range is described in this article, unless otherwise stated, the range is intended to include its end value and all integers and fractions within the range.

[0039] In these examples, parts and percentages are by mass unless otherwise indicated.

[0040] "Parts by mass" refers to the basic unit of measurement for expressing the mass ratio of multiple components. 1 part can represent any unit mass, such as 1g or 2.689g. If we say that the mass of component A is a parts and the mass of component B is b parts, it means the ratio of the mass of component A to the mass of component B is a:b. Alternatively, it means that the mass of component A is aK and the mass of component B is bK (K is an arbitrary number, indicating a multiple factor). It should not be misunderstood that, unlike the mass parts, the sum of the mass of all components is not limited to 100 parts.

[0041] "And / or" is used to indicate that one or both of the stated situations may occur, for example, A and / or B includes (A and B) and (A or B).

[0042] In order to solve the problem of poor weather resistance and water resistance and adhesion of moisture-curing silicone resin in the prior art.

[0043] In a first aspect, the present disclosure provides an adhesion promoter for moisture-curing silicone resin, the adhesion promoter comprising at least one of the compounds of the structure shown in Formula I:

[0044]

[0045] Among them, R 1 is one of hydrogen, C1-C20 alkyl, and aryl; R2 , R 3 Each is independently methyl or ethyl; R 4 is one of hydrogen, hydroxyl, and C1-C20 alkyl; R 5 is one of C1-C20 alkyl and C1-C20 alkyl-substituted aryl; X is 1,3-methylene or 1,6-ethyleneaminopropyl; a is 0 or 1.

[0046] The present invention adds a specific structure of adhesion promoter to moisture-curing silicone resin. On the one hand, the salicylate structural unit in the adhesion promoter has an ultraviolet absorption function, which can improve the weather resistance of the moisture-curing silicone resin. On the other hand, compared with aminosilane, the adhesion promoter containing the salicylate structural unit can improve the compatibility of the moisture-curing silicone resin with a plastic substrate (such as PET), thereby improving the adhesion and water-resistant adhesion between the moisture-curing silicone resin and the plastic substrate. On the third hand, the addition of the ultraviolet absorber to the moisture-curing silicone resin can improve the weather resistance of the moisture-curing silicone resin. , there are problems of poor solubility, easy migration and precipitation, resulting in decreased weather resistance, adhesion and water-resistant adhesion of moisture-curing silicone resin; the silicon-containing group in the adhesion promoter of the present invention improves the compatibility of the ultraviolet absorber with the moisture-curing silicone resin, avoids the migration and precipitation of the ultraviolet absorber in the moisture-curing silicone resin, and improves the weather resistance and water-resistant adhesion of the moisture-curing silicone resin; fourthly, compared with the primary amine group in the aminosilane coupling agent, the amine in the adhesion promoter is a secondary amine group, which reduces the alkalinity of the adhesion promoter and improves the water-resistant adhesion of the moisture-curing silicone resin.

[0047] In some embodiments, the adhesion promoter includes at least one of the following compounds:

[0048]

[0049] When the compound of the above structure is selected as the adhesion promoter, the weather resistance and water-resistant adhesion of the moisture-curing silicone resin can be further improved due to the further preferred effect of the groups contained in the structure.

[0050] In a second aspect, a method for preparing the adhesion promoter is provided, comprising the following steps:

[0051] Formaldehyde and aminosilane coupling agent are added to a solvent to dissolve, and then a catalyst is added, stirred evenly, and then salicylate is added, refluxed to react, and a reaction product is obtained; the reaction product is post-treated to obtain the adhesion promoter; wherein the molar ratio of salicylate: formaldehyde: aminosilane coupling agent is 1-3:1-3:1.

[0052] The present invention uses bio-based salicylate to react with formaldehyde and aminosilane to obtain an adhesion promoter containing salicylate structural units, and the obtained adhesion promoter has certain renewability, sustainability and environmental protection. The preparation method of the adhesion promoter disclosed in the present invention is a one-step synthesis method, the operation steps are simple, and it is easy to industrialize production.

[0053] Specifically, the molar ratio of salicylate:formaldehyde:aminosilane coupling agent can be, but is not limited to, 1:1:1, 1.5:1:1, 2:1:1, 2.5:1:1, 3:1:1, 1:1.5:1, 1:2:1, 1:2.5:1, 1:3:1, 2:2:1, 3:3:1.

[0054] Specifically, the chemical equation of the reaction in the above preparation method is as follows:

[0055]

[0056] In some embodiments, the aminosilane coupling agent is at least one of aminopropyltrimethoxysilane, aminopropyltriethoxysilane, aminoethylaminopropyltrimethoxysilane, aminoethylaminopropyltriethoxysilane, aminopropylmethyldimethoxysilane, aminopropylmethyltriethoxysilane, aminoethylaminopropylmethyldimethoxysilane and aminoethylaminopropylmethyldiethoxysilane;

[0057] In some embodiments, the catalyst is an acid, and the acid is at least one of hydrochloric acid, sulfuric acid, and trifluoroacetic acid.

[0058] Specifically, based on the total mass of formaldehyde and aminosilane coupling agent as 100%, the mass of the catalyst is 0.5-2%, for example, but not limited to 0.5%, 0.7%, 1.0%, 1.3%, 1.5%, 1.8%, 2%.

[0059] In some embodiments, the salicylate is phenyl salicylate and / or homosalate.

[0060] In some embodiments, the solvent is an alcohol solvent, illustratively, the solvent includes methanol and ethanol, and the amount of the solvent added is not particularly limited. Preferably, the mass of the solvent is 5-50% of the total mass of formaldehyde and the aminosilane coupling agent, and preferably, the mass of the solvent is 30-50% of the total mass of formaldehyde and the aminosilane coupling agent.

[0061] Specifically, the reflux reaction time is 4-12 hours, for example, it can be but not limited to 4 hours, 6 hours, 8 hours, 10 hours, 12 hours.

[0062] Specifically, the post-processing steps are:

[0063] After the reaction product is subjected to rotary evaporation to remove the solvent, a saturated sodium carbonate aqueous solution is added, stirred for 30-60 minutes, and then extracted with dichloromethane. The extracted product is washed with saturated brine until neutral, and the washed product is dried with anhydrous sodium sulfate, filtered, and the solvent is again removed by rotary evaporation to obtain an adhesion promoter.

[0064] In a third aspect, a use of the adhesion promoter in moisture-curing silicone resin is provided.

[0065] In a fourth aspect, a moisture-curing silicone resin is provided, comprising the following components in parts by weight: 100 parts of polydimethylsiloxane, 1-10 parts of a cross-linking agent, 5-100 parts of a filler, 1-30 parts of a plasticizer, 0.01-5 parts of a catalyst, and 0.1-5 parts of an adhesion promoter as described in claim 1 or 2.

[0066] For example, in different embodiments, the weight proportion of the cross-linking agent may be, but is not limited to, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, or 10 parts.

[0067] For example, in different embodiments, the weight proportion of the plasticizer may be, but is not limited to, 1 part, 3 parts, 8 parts, 10 parts, 14 parts, 17 parts, 20 parts, 25 parts, 27 parts, or 30 parts.

[0068] For example, in different embodiments, the weight proportion of the filler may be, but is not limited to, 5, 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100 parts.

[0069] For example, in different embodiments, the weight portion of the catalyst may be, but is not limited to, 0.01 parts, 0.1 parts, 0.5 parts, 1 parts, 1.5 parts, 2 parts, 3 parts, 4 parts, 4.5 parts, or 5 parts.

[0070] For example, in different embodiments, the weight proportion of the adhesion promoter may be, but is not limited to, 0.1, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, or 5 parts.

[0071] In the present disclosure, if the content of the adhesion promoter is too low, it will not play the role of the adhesion promoter, and the weather resistance, adhesion and water-resistant adhesion of the resulting moisture-curing silicone resin will be reduced; if the amount of the adhesion promoter is too much, the enhanced strength of the weather resistance, adhesion and water-resistant adhesion of the resulting moisture-curing silicone resin will not be obvious, resulting in a waste of resources.

[0072] In some embodiments, the polydimethylsiloxane is at least one of α,ω-dihydroxy polydimethylsiloxane and methyldimethoxy-terminated polydimethylsiloxane;

[0073] In some embodiments, the viscosity of the polydimethylsiloxane at 25° C. is 1000-150000 mPa·s, for example, it can be but not limited to 1000 mPa·s, 3000 mPa·s, 7000 mPa·s, 10000 mPa·s, 30000 mPa·s, 50000 mPa·s, 80000 mPa·s, 100000 mPa·s, 120000 mPa·s, and 150000 mPa·s.

[0074] In some embodiments, the crosslinking agent is at least one of ketoxime silane and alkoxy silane.

[0075] Specifically, the ketoxime silane is at least one of methyltributylacetoximine silane, vinyltributylacetoximine silane and tetrabutylketoxime silane.

[0076] Specifically, the alkoxysilane is at least one of methyltrimethoxysilane, vinyltrimethoxysilane, propyltrimethoxysilane, methyl orthosilicate, and ethyl orthosilicate.

[0077] In some embodiments, the filler is at least one of calcium carbonate, diatomaceous earth, quartz sand, and white carbon black.

[0078] In some embodiments, the plasticizer is at least one of mineral oil and dimethyl silicone oil;

[0079] In some embodiments, the catalyst is at least one of an organic tin catalyst and an organic titanium catalyst.

[0080] Specifically, the organotin catalyst is at least one of dibutyltin diacetate, dibutyltin dilaurate, dioctyltin dilaurate, stannous octoate, and dibutyltin acetylacetonate;

[0081] Specifically, the organic titanium catalyst is at least one of tetrabutyl titanate, tetra-tert-butyl titanate, diisopropoxy titanium diacetylacetonate, and diisopropoxy titanium diacetylacetate.

[0082] In some embodiments, the moisture-curing silicone resin further includes 0.01-5 parts by weight of a silane coupling agent, wherein the silane coupling agent is at least one of γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, 2-(3,4-epoxycyclohexane)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexane)ethyltriethoxysilane, γ-(glycidoxy)propylmethyltrimethoxysilane, and γ-(glycidoxy)propylmethyltriethoxysilane.

[0083] In a fifth aspect, a use of the moisture-curing silicone resin in a sealant is provided.

[0084] In order to further illustrate the present invention, the adhesion promoter for moisture-curing silicone resin provided by the present invention and its preparation method and application are described in detail below in conjunction with embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0085] Example 1

[0086] This embodiment provides an adhesion promoter, and the structural formula of the adhesion promoter in this embodiment is:

[0087] Marked as ZJ-1.

[0088] The preparation method of the adhesion promoter of this embodiment comprises the following steps:

[0089] In a four-necked flask equipped with a thermometer, a dropping funnel, a mechanical stirrer, and a condenser, 11.3 g of 37% formaldehyde aqueous solution, 17.9 g of aminopropyltrimethoxysilane, and 50 g of ethanol were added in sequence, stirring was started, 0.5 g of hydrochloric acid was added, and the mixture was stirred at room temperature for 30 min; then 21.4 g of phenyl salicylate was added, and the temperature was raised to reflux for 5 h; after the solvent was removed by rotary evaporation, 20 mL of saturated sodium bicarbonate aqueous solution was added, and the mixture was stirred for 30 min. The mixture was extracted with 50 mL of dichloromethane, then washed with saturated brine until neutral, dried over anhydrous sodium sulfate, filtered, and the solvent was removed by rotary evaporation to obtain the adhesion promoter; the H-NMR spectrum data of the obtained adhesion promoter are as follows: 0.57 (2H), 1.5 (2H), 2.5 (2H), 3.55 (9H), 3.8 (2H), 6.85 (1H), 7.14-7.16 (4H), 7.33 (2H), 7.78 (1H).

[0090] Example 2

[0091] This embodiment provides an adhesion promoter, and the structural formula of the adhesion promoter in this embodiment is:

[0092] Marked as ZJ-2.

[0093] The preparation method of the adhesion promoter of this embodiment comprises the following steps:

[0094] In a four-necked flask equipped with a thermometer, a dropping funnel, a mechanical stirrer, and a condenser, 12.1 g of a 37% formaldehyde aqueous solution, 17.9 g of aminopropyltrimethoxysilane, and 50 g of ethanol were added in sequence, stirring was started, 0.5 g of hydrochloric acid was added, and the mixture was stirred at room temperature for 30 min; then 25.0 g of 2-ethylhexyl salicylate was added, and the temperature was raised to reflux for reaction for 8 h; after the solvent was removed by rotary evaporation, 20 mL of a saturated sodium bicarbonate aqueous solution was added, the mixture was stirred for 30 min, extracted with 50 mL of dichloromethane, and then saturated with water. The mixture was washed with brine until neutral, dried over anhydrous sodium sulfate, filtered, and the solvent was removed by rotary evaporation to obtain the adhesion promoter; the H NMR spectrum data of the obtained adhesion promoter were as follows: 0.56 (2H), 1.05-1.22 (18H), 1.32 (2H), 1.5 (2H), 1.6 (1H), 1.78-1.82 (4H), 2.5 (2H), 3.8-3.85 (8H), 3.9 (1H), 6.8 (1H), 7.10 (1H), 7.6 (1H).

[0095] Example 3

[0096] This embodiment provides an adhesion promoter, and the structural formula of the adhesion promoter in this embodiment is:

[0097] Marked as ZJ-3.

[0098] The preparation method of the adhesion promoter of this embodiment comprises the following steps:

[0099] In a four-necked flask equipped with a thermometer, a dropping funnel, a mechanical stirrer, and a condenser, 12.1 g of 37% formaldehyde aqueous solution, 17.9 g of aminopropyltrimethoxysilane, and 50 g of ethanol were added in sequence, stirring was started, 0.5 g of hydrochloric acid was added, and the mixture was stirred at room temperature for 30 min; then 25.0 g of 2-ethylhexyl salicylate was added, and the temperature was raised to reflux for reaction for 8 h; after the solvent was removed by rotary evaporation of the reaction product, 20 mL of saturated sodium bicarbonate aqueous solution was added, and the mixture was stirred for 30 min, and 50 mL of dichloromethane was used. The mixture was extracted, and then washed with saturated brine until neutral, dried over anhydrous sodium sulfate, filtered, and the solvent was removed by rotary evaporation to obtain the adhesion promoter; the H-NMR spectrum data of the obtained adhesion promoter are as follows: 0.58 (2H), 0.96 (6H), 1.25-1.33 (9H), 1.5 (2H), 2.55-2.67 (6H), 3.55 (9H), 3.8 (2H), 4.2 (2H), 6.8 (1H), 7.1 (1H), 7.6 (1H).

[0100] Example 4

[0101] This embodiment provides an adhesion promoter, and the structural formula of the adhesion promoter in this embodiment is:

[0102] Marked as ZJ-4.

[0103] The preparation method of the adhesion promoter of this embodiment comprises the following steps:

[0104] In a four-necked flask equipped with a thermometer, a dropping funnel, a mechanical stirrer, and a condenser, 16.2 g of 37% formaldehyde aqueous solution, 22.2 g of aminoethylaminopropyltrimethoxysilane, and 60 g of ethanol were added in sequence, stirring was started, 0.5 g of hydrochloric acid was added, and the mixture was stirred at room temperature for 30 min; then 50 g of 2-ethylhexyl salicylate was added, and the temperature was raised to reflux for reaction for 8 h; after the solvent was removed by rotary evaporation of the reaction product, 20 mL of saturated sodium bicarbonate aqueous solution was added, the mixture was stirred for 30 min, extracted with 100 mL of dichloromethane, and then saturated sodium bicarbonate was added. The mixture was washed with brine until neutral, dried over anhydrous sodium sulfate, filtered, and the solvent was removed by rotary evaporation to obtain the adhesion promoter; the H NMR spectrum data of the obtained adhesion promoter were as follows: 0.56 (2H), 0.95 (12H), 1.25-1.33 (16H), 1.45 (2H), 2.0 (2H), 2.36-2.65 (6H), 3.5 (9H), 3.6 (2H), 3.8 (2H), 4.2 (4H), 6.8 (2H), 7.1 (2H), 7.6 (2H).

[0105] Example 5

[0106] This embodiment provides a moisture-curable silicone resin composition, and the preparation method thereof is as follows:

[0107] 60 parts by weight of α,ω-dihydroxypolydimethylsiloxane having a viscosity of 50 Pa·s at 25°C, 3.0 parts by weight of methyltributylacetonato silane, 1.0 parts by weight of vinyltributylacetonato silane, 35 parts by weight of calcium carbonate treated with stearic acid, 5 parts by weight of dimethyl silicone oil having a viscosity of 350 mPa·s at 25°C, 0.02 parts by weight of dibutyltin dilaurate, 1.2 parts by weight of adhesion promoter ZJ-1 and 0.32 parts by weight of glycidyloxypropyltrimethoxysilane are degassed and mixed in a universal mixer to obtain a moisture-curing silicone resin composition.

[0108] Example 6

[0109] This embodiment provides a moisture-curable silicone resin composition, which differs from Embodiment 5 only in that adhesion promoter ZJ-2 is used to replace adhesion promoter ZJ-1, and the other components and amounts remain unchanged.

[0110] Example 7

[0111] This embodiment provides a moisture-curable silicone resin composition, which differs from Embodiment 5 only in that the adhesion promoter ZJ-1 is replaced by the adhesion promoter ZJ-3, and the other components and amounts remain unchanged.

[0112] Example 8

[0113] This embodiment provides a moisture-curable silicone resin composition, which is different from Embodiment 5 only in that the adhesion promoter ZJ-1 is replaced by the adhesion promoter ZJ-4, and the other components and amounts remain unchanged.

[0114] Example 9

[0115] This embodiment provides a moisture-curing silicone resin composition, which is different from Embodiment 5 only in that the weight portion of the adhesion promoter ZJ-1 is 0.06 parts, and the other components and amounts remain unchanged.

[0116] Example 10

[0117] This embodiment provides a moisture-curable silicone resin composition, which is different from Embodiment 5 only in that the weight portion of the adhesion promoter ZJ-1 is 2.1 parts, and the other components and amounts remain unchanged.

[0118] Embodiment 11

[0119] This embodiment provides a moisture-curable silicone resin composition, which is different from Embodiment 5 only in that the weight portion of the adhesion promoter ZJ-1 is 3 parts, and the other components and amounts remain unchanged.

[0120] Example 12

[0121] This embodiment provides a moisture-curing silicone resin composition, which is different from Embodiment 5 only in that the weight portion of the adhesion promoter ZJ-1 is 4 parts, and the other components and amounts remain unchanged.

[0122] Embodiment 13

[0123] This embodiment provides a moisture-curing silicone resin composition, which differs from Embodiment 5 only in that the weight portion of glycidyloxypropyltrimethoxysilane is 0 parts, and the other components and amounts remain unchanged, that is, glycidyloxypropyltrimethoxysilane is not added in this embodiment.

[0124] Embodiment 14

[0125] This embodiment provides a moisture-curable silicone resin composition, and the preparation method thereof is as follows:

[0126] 60 parts by weight of α,ω-dihydroxypolydimethylsiloxane having a viscosity of 50 Pa·s at 25°C, 0.4 parts by weight of methyltributylacetonato silane, 0.2 parts by weight of vinyltributylacetonato silane, 60 parts by weight of diatomaceous earth, 0.6 parts by weight of dimethyl silicone oil having a viscosity of 350 mPa·s at 25°C, 3 parts by weight of dibutyltin dilaurate, 1.2 parts by weight of adhesion promoter ZJ-1 and 3 parts by weight of glycidyloxypropyltrimethoxysilane are degassed and mixed in a universal mixer to obtain a moisture-curing silicone resin composition.

[0127] Embodiment 15

[0128] This embodiment provides a moisture-curable silicone resin composition, and the preparation method thereof is as follows:

[0129] 60 parts by weight of α,ω-dihydroxypolydimethylsiloxane having a viscosity of 50 Pa·s at 25°C, 4.5 parts by weight of methyltributylacetonato silane, 1.5 parts by weight of vinyltributylacetonato silane, 3 parts by weight of calcium carbonate treated with stearic acid, 30 parts by weight of dimethyl silicone oil having a viscosity of 350 mPa·s at 25°C, 1 part by weight of dibutyltin dilaurate, 1.2 parts by weight of adhesion promoter ZJ-1 and 3 parts by weight of glycidyloxypropyltrimethoxysilane are degassed and mixed in a universal mixer to obtain a moisture-curing silicone resin composition.

[0130] Comparative Example 1

[0131] This comparative example provides a moisture-curing silicone resin composition, which differs from Example 5 only in that the adhesion promoter ZJ-1 is replaced by γ-aminopropyltriethoxysilane, and the other components and amounts remain unchanged.

[0132] Comparative Example 2

[0133] This comparative example provides a moisture-curing silicone resin composition, which differs from Example 5 only in that the weight portion of the adhesion promoter ZJ-1 is 0 parts, and the other components and amounts remain unchanged, that is, no adhesion promoter is added in this comparative example.

[0134] Performance Testing

[0135] The moisture-curable silicone resin compositions obtained in the examples and comparative examples were used to prepare H-type adhesive test pieces (using Al-PBT substrate) according to the method provided in Chapter 7 of GB / T13477.8-2002, and vulcanized and cured for 7 days in an environment with a temperature of (23±2)°C and a relative humidity of (50±5)%. The H-type adhesive test pieces were then subjected to the following tests, and the test conditions and test results are shown in Table 1.

[0136] Table 1

[0137]

[0138]

[0139] Note: Adhesive strength retention rate refers to the ratio of the adhesive strength after 168 hours of immersion in water at 45°C + UV irradiation to the adhesive strength after 7 days of placement under standard conditions at 23°C.

[0140] From the experimental data in Table 1, it can be seen that the moisture-hardening silicone resin prepared by the adhesion promoter of the present invention has a bonding strength greater than 1.0 MPa, a bonding strength retention rate greater than 85%, and a bonding failure area less than 10% after being placed under standard conditions for 7 days, immersed in water at 23°C for 28 days, and immersed in water at 45°C + irradiated with ultraviolet light for 168 hours. This indicates that the adhesion promoter of the present invention can effectively improve the adhesion of the moisture-hardening silicone resin to the PBT substrate, and improve the weather resistance and water-resistant adhesion of the moisture-hardening silicone resin.

[0141] By comparing Example 5, Examples 9-12 and Comparative Example 2, it can be seen that the weight of the adhesion promoter affects the performance of the moisture-curing silicone resin. When the weight of the adhesion promoter is 1.2-3 parts, the weather resistance and water-resistant adhesion of the obtained moisture-curing silicone resin are better.

[0142] By comparing Example 5, Example 13 and Comparative Example 1, it can be seen that in Comparative Example 1, a primary amine silane coupling agent is used, and the resulting moisture-hardening silicone resin has a bonding failure area of ​​100% after being immersed in water at 23°C for 28 days and immersed in water at 45°C + irradiated with ultraviolet light for 168 hours, i.e., complete debonding; this indicates that compared with the primary amine silane coupling agent, the adhesion promoter disclosed in the present invention can effectively improve the weather resistance and water-resistant adhesion of the moisture-hardening silicone resin.

[0143] Finally, it should be noted that the above embodiments are used to illustrate the technical solution of the present disclosure rather than to limit the protection scope of the present disclosure. Although the present disclosure has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present disclosure can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present disclosure.

Claims

1. An adhesion promoter for moisture-curing silicone resin, characterized in that The adhesion promoter includes at least one of the compounds of the structure shown in Formula I: Among them, R 1 is one of hydrogen, C1-C20 alkyl, and aryl; R 2 , R 3 Each is independently methyl or ethyl; R 4 is one of hydrogen, hydroxyl, and C1-C20 alkyl; R 5 is one of C1-C20 alkyl and C1-C20 alkyl-substituted aryl; X is 1,3-methylene or 1,6-ethyleneaminopropyl; a is 0 or 1.

2. The adhesion promoter for moisture-curing silicone resin according to claim 1, characterized in that: The adhesion promoter includes at least one of the following compounds:

3. A method for preparing a moisture-curing silicone resin adhesion promoter as claimed in claim 1 or 2, characterized in that: The following steps are involved: Formaldehyde and aminosilane coupling agent are added to a solvent to dissolve, and then a catalyst is added, stirred evenly, and then salicylate is added, refluxed to react, and a reaction product is obtained; the reaction product is post-treated to obtain the adhesion promoter; wherein the molar ratio of salicylate: formaldehyde: aminosilane coupling agent is 1-3:1-3:

1.

4. The method for preparing a moisture-curing silicone resin adhesion promoter according to claim 3, characterized in that: The aminosilane coupling agent is at least one of aminopropyltrimethoxysilane, aminopropyltriethoxysilane, aminoethylaminopropyltrimethoxysilane, aminoethylaminopropyltriethoxysilane, aminopropylmethyldimethoxysilane, aminopropylmethyltriethoxysilane, aminoethylaminopropylmethyldimethoxysilane and aminoethylaminopropylmethyldiethoxysilane; And / or, the catalyst is an acid, and the acid is at least one of hydrochloric acid, sulfuric acid and trifluoroacetic acid; And / or, the salicylate is phenyl salicylate and / or homosalate; And / or, the solvent is an alcohol solvent.

5. Use of the adhesion promoter for moisture-curing silicone resin according to claim 1 or 2 in moisture-curing silicone resin.

6. A moisture-curing silicone resin, characterized in that: The invention comprises the following components in parts by weight: 100 parts of polydimethylsiloxane, 1-10 parts of a crosslinking agent, 5-100 parts of a filler, 1-30 parts of a plasticizer, 0.01-5 parts of a catalyst, and 0.1-5 parts of an adhesion promoter as claimed in claim 1 or 2.

7. The moisture-curable silicone resin according to claim 6, wherein: The polydimethylsiloxane is at least one of α,ω-dihydroxy polydimethylsiloxane and methyldimethoxy-terminated polydimethylsiloxane; And / or, the viscosity of the polydimethylsiloxane at 25° C. is 1000-150000 mPa·s; And / or, the cross-linking agent is at least one of ketoxime silane and alkoxy silane; And / or, the filler is at least one of calcium carbonate, diatomaceous earth, quartz sand, and white carbon black And / or, the plasticizer is at least one of mineral oil and dimethyl silicone oil; And / or, the catalyst is at least one of an organic tin catalyst and an organic titanium catalyst.

8. The moisture-curable silicone resin according to claim 7, wherein: The ketoxime silane is at least one of methyltributylacetoximosilane, vinyltributylacetoximosilane and tetrabutylketoxime silane; And / or, the alkoxysilane is at least one of methyltrimethoxysilane, vinyltrimethoxysilane, propyltrimethoxysilane, methyl orthosilicate, and ethyl orthosilicate; And / or, the organotin catalyst is at least one of dibutyltin diacetate, dibutyltin dilaurate, dioctyltin dilaurate, stannous octoate, and dibutyltin acetylacetonate; And / or, the organic titanium catalyst is at least one of tetrabutyl titanate, tetra-tert-butyl titanate, diisopropoxy titanium diacetylacetonate, and diisopropoxy titanium diacetylacetate.

9. The moisture-curable silicone resin according to claim 6, wherein: The moisture-curing silicone resin also includes 0.01-5 parts by weight of a silane coupling agent, which is at least one of γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, 2-(3,4-epoxycyclohexane)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexane)ethyltriethoxysilane, γ-(glycidoxy)propylmethyltrimethoxysilane, and γ-(glycidoxy)propylmethyltriethoxysilane.

10. Use of the moisture-hardening silicone resin according to any one of claims 6 to 9 in sealants.

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