Polydiene liquid rubber with functionalized chain as well as preparation method and application thereof

Abstract

The invention relates to the technical field of rubber modification, in particular to chain-functionalized polydiene liquid rubber as well as a preparation method and application thereof. According to the chain-functionalized polydiene liquid rubber provided by the invention, a main chain comprises a polydiene molecular chain, and a side chain contains a silicon-based functional group; on the basis of the total number of repetitive units of the functionalized polydiene liquid rubber in the chain, the functionalization degree of the silicon-based functional group is 0.01-9.86%. According to the in-chain functionalized polydiene liquid rubber provided by the invention, a silicon-based functional group is in a chain instead of a chain end, so that the functionalization degree is greatly improved, and the problems that the internal acting force of a material is not uniform and stress concentration is easy to occur due to the fact that the functional group is distributed and concentrated at the chain end can be solved. Moreover, due to the fact that the silicon-based functional group is located in the chain, when the in-chain functionalized polydiene liquid rubber is used for a crosslinking reaction, crosslinking points are evenly distributed, and the mechanical property of a material is excellent.

Description

Technical Field

[0001] This invention relates to the field of rubber modification technology, specifically to a chain-functionalized polydiene liquid rubber, its preparation method, and its application. Background Technology

[0002] Liquid rubber is a class of linear or branched polymers that are liquid at room temperature and typically have a number-average molecular weight of 1000–10000 g / mol. Due to its good flowability and ease of processing, it is widely used in adhesives, coatings, sealants, and composite materials. To further improve the performance of liquid rubber, functionalization modification is usually required. Current methods for preparing functionalized liquid rubbers mainly focus on chain-end functionalization, that is, introducing functional groups to both ends of the molecular chain through initiators or terminators. However, chain-end functionalization has significant drawbacks: first, the number of functional groups is limited, making it difficult to significantly enhance the interfacial interaction between the rubber and other materials (such as fillers like silica); second, the functional groups are concentrated at the chain ends, leading to uneven internal forces and stress concentration; and third, when used in crosslinking reactions, the crosslinking points are sparsely distributed, affecting the mechanical properties of the product. Therefore, providing a liquid rubber with good interfacial interaction with other materials and excellent mechanical properties is of great significance. Summary of the Invention

[0003] In view of this, the purpose of this invention is to provide a chain-functionalized polydiene liquid rubber, its preparation method, and its applications. The chain-functionalized polydiene liquid rubber provided by this invention exhibits strong compatibility with other materials and excellent interfacial interactions, as well as superior mechanical properties.

[0004] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a chain-functionalized polydiene liquid rubber, wherein the main chain comprises a polydiene molecular chain and the side chain contains silicon-based functional groups; Based on the total number of repeating units of the functionalized polydiene liquid rubber in the chain, the degree of functionalization of the silicon-based functional groups is 0.01~9.86%.

[0005] Preferably, the polydiene molecular chain includes a diene homopolymer molecular chain or a diene copolymer molecular chain; The diene homopolymer molecular chain has at least one of cis-1,4-structural units, trans-1,4-structural units, and 1,2-structural units; the diene copolymer molecular chain includes at least one of polybutadiene molecular chain, polyisoprene molecular chain, butadiene-styrene copolymer molecular chain, and butadiene-isoprene copolymer molecular chain.

[0006] Preferably, the silicon-based functional group has the structural formula -Si(R1)(R2)(R3), wherein R1, R2 and R3 are independently hydrogen, alkyl, alkoxy or aryl, and at least one of R1, R2 and R3 is alkoxy.

[0007] Preferably, the functionalized polydiene liquid rubber in the chain has a cyclic structure, which includes five-membered rings and / or six-membered rings; the cyclic structure accounts for 0 to 80% of the total structural units of the molecular chain.

[0008] Preferably, the number-average molecular weight of the functionalized polydiene liquid rubber in the chain is 0.34 × 10⁻⁶. 4 ~7.56×10 4 g / mol, with a molecular weight distribution index of 1.05~3.22.

[0009] Preferably, the functionalized polydiene liquid rubber in the chain has a structure shown in any one of formulas I to III: Formula I; Formula II; Formula III; Wherein, R1, R2 and R3 are independently hydrogen, alkyl, alkoxy or aryl, and at least one of R1, R2 and R3 is alkoxy; X has any of the following structures: ; In Equation I, taking a'+b'+c'+d'=100 as an example, a'=2.73~95.91, b'=0~73.89, c'=2.33~83.17, and d'=0~4.70; In formulas II to III, taking a'+b'+c'+d'+e'=100 as an example, a'=21.35~25.60, b'=4.32~25.94, c'=12.35~30.98, d'=1.34~2.64, and e'=38.60~45.60.

[0010] The present invention also provides a method for preparing the chain-functionalized polydiene liquid rubber described in the above technical solution, including method 1 and method 2; Method 1 includes the following steps: mixing a solution of diene unsaturated rubber, a hydrosilylation reagent and an olefin metathesis catalyst, and carrying out a modification reaction to obtain a chain-functionalized polydiene liquid rubber. Method 2 includes the following steps: pre-reacting an olefin metathesis catalyst with a hydrosilylation reagent to obtain a pre-reaction mixture; mixing the pre-reaction mixture with a solution of diene unsaturated rubber to carry out a modification reaction to obtain a chain-functionalized polydiene liquid rubber. The olefin metathesis catalyst includes ruthenium-based olefin metathesis catalysts.

[0011] Preferably, in method 1 and method 2: The diene-based unsaturated rubber includes butadiene homopolymer or butadiene copolymer; the butadiene homopolymer has at least one of cis-1,4-structural units, trans-1,4-structural units and 1,2-structural units; the butadiene copolymer includes at least one of polybutadiene, butadiene-styrene copolymer and butadiene-isoprene copolymer. The chemical formula of the hydrosilylation reagent is SiH(R1)(R2)(R3); The molar ratio of C=C double bonds to hydrosilylation reagent in the diene-based unsaturated rubber is 100:0.01~50; The molar ratio of C=C double bonds and olefin metathesis catalyst in the diene unsaturated rubber is 100:0.1~5; The number-average molecular weight of the diene-based unsaturated rubber is 1×10⁻⁶. 4 ~15×10 4 g / mol, with a molecular weight distribution index of 1.25~3.0; The solvent in the diene unsaturated rubber solution includes at least one of aliphatic hydrocarbon solvents, aromatic hydrocarbon solvents, chlorinated hydrocarbon solvents, and tetrahydrofuran; The modification reaction is carried out at a temperature of 25~120℃ for a time of 0.5~10h; the in-situ modification reaction is carried out under anhydrous and oxygen-free conditions.

[0012] Preferably, in method 2, the temperature of the pre-reaction is 25~120℃ and the time is 0.2~8h; the pre-reaction is carried out under anhydrous and oxygen-free conditions.

[0013] The present invention also provides the application of the in-chain functionalized polydiene liquid rubber described in the above technical solution or the in-chain functionalized polydiene liquid rubber prepared by the preparation method described in the above technical solution in adhesives, coatings, sealants or composite materials.

[0014] This invention provides an in-chain functionalized polydiene liquid rubber, wherein the main chain comprises a polydiene molecular chain and the side chains contain silicon-based functional groups. Based on the total number of repeating units in the in-chain functionalized polydiene liquid rubber, the functionalization degree of the silicon-based functional groups is 0.01~9.86%. In the in-chain functionalized polydiene liquid rubber provided by this invention, the silicon-based functional groups are located in the middle of the chain rather than at the chain ends, which not only greatly improves the functionalization degree but also solves the problem of uneven internal forces and stress concentration caused by the concentration of functional groups at the chain ends. Furthermore, because the silicon-based functional groups are located in the middle of the chain, the in-chain functionalized polydiene liquid rubber provided by this invention exhibits a uniform distribution of crosslinking points during crosslinking reactions, resulting in excellent mechanical properties of the material.

[0015] This invention employs a highly active ruthenium-based olefin metathesis catalyst, using diene-based unsaturated rubber as the reaction substrate and a hydrosilylation agent as the functionalizing agent. It can selectively catalyze the metathesis and hydrosilylation reactions of vinyl carbon-carbon double bonds in the unsaturated rubber molecular chain, achieving uniform distribution and controllable introduction of functional groups into the molecular chain backbone, ultimately yielding a functionalized diene-based liquid rubber. Furthermore, the preparation method provided by this invention is simple, easy to operate, and has low production costs, making it suitable for industrial production. The preparation method provided by this invention has significant practical implications for expanding the types of liquid polybutadiene products and increasing their application range.

[0016] This invention employs methods 1 and 2 to prepare in-chain functionalized polydiene liquid rubber. By changing the feeding method and the proportion of raw materials, the functionalization degree and molecular weight of the in-chain functionalized polydiene liquid rubber can be controlled. Method 2, used in this invention to prepare in-chain functionalized polydiene liquid rubber, is more conducive to suppressing the formation of cyclization byproducts and simultaneously achieving controllable molecular weight and degree of hydrosilylation.

[0017] The preparation method provided by this invention has relatively mild reaction conditions, can occur under normal pressure, has strong compatibility with different hydrosilylation reagents, and can flexibly prepare hydrosilylation liquid polybutadiene, butadiene-styrene copolymer or butadiene-isoprene copolymer products with diverse functional groups. Attached Figure Description

[0018] Figure 1 The hydrogen NMR spectrum of the chain-functionalized polybutadiene liquid rubber prepared in Example 1; Figure 2 The carbon NMR spectrum of the chain-functionalized polybutadiene liquid rubber prepared in Example 1; Figure 3 The 1H NMR spectra of the chain-functionalized polybutadiene liquid rubbers prepared in Examples 1, 4-6 and Comparative Example 2 are shown below. Figure 4The microstructure content diagram shows the content of the in-chain functionalized polybutadiene liquid rubbers prepared in Examples 1 and 7-9. Figure 5 The graph shows the change in molecular weight of the chain-functionalized polybutadiene liquid rubbers prepared in Examples 1 and 18-22. Figure 6 The water contact angle variation diagrams are for the liquid rubbers prepared in Example 1 (ii) and Comparative Example 2 (i). Detailed Implementation

[0019] This invention provides a chain-functionalized polydiene liquid rubber, wherein the main chain comprises a polydiene molecular chain and the side chains contain silicon-based functional groups.

[0020] In this invention, the polydiene molecular chain preferably includes a diene homopolymer molecular chain or a diene copolymer molecular chain; the diene homopolymer molecular chain preferably has at least one of cis-1,4-structural units, trans-1,4-structural units, and 1,2-structural units, specifically one, two, or three of cis-1,4-structural units, trans-1,4-structural units, and 1,2-structural units; the diene copolymer molecular chain preferably includes at least one of polybutadiene molecular chains, polyisoprene molecular chains, butadiene-styrene copolymer molecular chains, and butadiene-isoprene copolymer molecular chains.

[0021] In this invention, the preferred structural formula of the silicon-based functional group is -Si(R1)(R2)(R3), wherein R1, R2, and R3 are independently preferably hydrogen, alkyl, alkoxy, or aryl, and at least one of R1, R2, and R3 is an alkoxy group. In this invention, the alkyl group preferably includes C1-C15 alkyl groups, more preferably C1-C6 alkyl groups, and may specifically include methyl, ethyl, propyl, butyl, pentyl, or hexyl. In this invention, the alkoxy group preferably includes C1-C15 alkoxy groups, more preferably C1-C6 alkoxy groups, and may specifically include methoxy, ethoxy, propoxy, butoxy, pentoxy, or hexoxy groups. In this invention, the aryl group preferably includes phenyl, 4-methylphenyl, 3-methylphenyl, 2-methylphenyl, 4-chlorophenyl, 4-methoxyphenyl, or 4-dimethylaminophenyl. In this invention, -Si(R1)(R2)(R3) preferably includes -Si(OCH3)3, -Si(OCH2CH3)3, -Si(OCH3)2(CH3), -Si(OCH2CH3)2(CH3), -Si(OCH2CH3)(CH3)2, -Si(OCH3)(CH3)2, -Si(OCH2CH3)2(CH2CH3), -Si(OC6H5)(CH3)2 or -Si(OC6H5)3.

[0022] In this invention, the in-chain functionalized polydiene liquid rubber preferably has a cyclic structure, which preferably includes five-membered rings and / or six-membered rings; the cyclic structure preferably accounts for 0-80% of the total structural units of the molecular chain, specifically 0.1%, 0.5%, 1%, 5%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, or 80%. In this invention, the five-membered ring preferably includes in-chain and / or chain-end five-membered rings, which may specifically include... or In this invention, the six-membered ring preferably includes a chain-end six-membered ring, and the six-membered ring may specifically include... .

[0023] In this invention, the in-chain functionalized polydiene liquid rubber preferably has the structure shown in any one of formulas I to III, wherein formula I is the structural formula of the in-chain functionalized polybutadiene liquid rubber, formula II is the structural formula of the in-chain functionalized butadiene-styrene copolymer liquid rubber, and formula III is the structural formula of the in-chain functionalized butadiene-isoprene copolymer liquid rubber. Formula I; Formula II; Formula III.

[0024] In this invention, X (terminal group) in formulas I to III preferably has any one of the following structures: In this invention, the definitions of R1, R2, and R3 in formulas I to III are the same as the definitions of R1, R2, and R3 in -Si(R1)(R2)(R3). In this invention, R1 in formulas I to III more preferably includes methyl, methoxy, or ethoxy; R2 in formulas I to III more preferably includes methyl or ethyl; and R3 in formulas I to III more preferably includes methyl or ethyl.

[0025] In this invention, in formula I, taking a'+b'+c'+d'=100 as a, a'=2.73~95.91, specifically 2.73, 2.80, 3, 3.32, 3.34, 3.57, 3.58, 3.87, 4, 4.51, 5, 5.01, 5.37, 5.91, 6, 7, 7.57, 8, 9, 9.38, 9.44, 9.60, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 7 0, 75, 80, 85, 90, 95, 95.91, 96%, 97% or 97.06; b' = 0~73.89, specifically 0, 1, 2, 2.81, 3, 4, 5, 5.59, 6, 7, 8, 9, 10, 10.79, 15, 20, 25, 30, 33.56, 33.59, 34.40, 35, 39.63, 39.84, 40, 41.49, 41.78, 45, 50, 50.08, 55, 58.79, 60, 62.82, 65, 66.89, 70, 70.97, 71.60 or 73.89; c'=2.33~83.17, specifically 2.33, 3, 3.45, 5, 10, 15, 19.21, 20, 24.34, 25, 25.16, 27.42, 30, 34.14, 35, 37.79, 40, 44.07, 50, 53.33, 54.32, 54.36, 54.69, 54.98, 60, 60.63, 61 .07, 65, 70, 75, 77.37, 80, 81.85 or 83.17; d'=0~4.70, specifically 0, 0.31, 0.48, 0.5, 0.56, 0.6, 0.61, 0.62, 0.64, 0.7, 0.8, 0.83, 0.84, 0.99, 1, 1.27, 1.5, 1.60, 2, 2.11, 2.24, 2.35, 2.5, 3, 3.12, 3.5, 4, 4.5, 4.64 or 4.70.

[0026] In this invention, the formula I, a':b':c':d', can specifically be 3.57:39.63:54.69:2.11, 95.91:0:3.45:0.64, 97.06:0:2.33:0.61, 3.34:41.78:54.32:0.56, 3.32:41.49:54.36:0.83, 3.58:39.84:54.98:1.60, 9.60:10.79:77.37:2.24, 9.44:5.59:81.85:3.12, 9.38:2.81:83.17:4.64, 3.87:70.97:25.16:0, 2.73:62.82:34.14:0.31, 2.80:58.79:37.79:0.62, 4.51:33.59:60.63:1.27, 3.58:71.60:24.34:0.48, 5.91:73.89:19.21:0.99, 7.57:34.40:53.33:4.70, 5.01:50.08:44.07:0.84, 3.34:66.89:27.42:2.35 or 5.37:33.56:61.07:0.

[0027] In this invention, in formulas II to III, taking a'+b'+c'+d'+e'=100 as a, a'=21.35~25.60, specifically 21.35, 21.52, 21.5, 22, 22.5, 22.56, 23, 23.5, 23.60, 23.84, 24, 24.12, 24.35, 24.60, 24.86, 25, 25.31, 25.5, or 2 5.60; b' = 4.32~25.94, specifically 4.32, 5, 6.27, 7.56, 7.86, 8.46, 9.86, 10, 11.13, 13.63, 15, 15.64, 20, 21.34, 22, 23, 24, 25 or 25.94; c' = 12.35~30.98, specifically 12.35, 13, 13.61, 14, 14.6, 15 16, 17, 18, 18.08, 18.98, 19, 19.12, 19.77, 20, 20.04, 21, 21.36, 22, 23, 24, 25, 25.36, 26, 27, 28, 29, 29.68, 30 or 30.98; d'=1.34~2.64, specifically 1.34, 1.46, 1.5, 1.56, 1.6, 1.76, 1.8, 1 .9, 2, 2.1, 2.11, 2.15, 2.2, 2.3, 2.35, 2.36, 2.4, 2.45, 2.50, 2.56, 2.6 or 2.64; e'=38.60~45.60, specifically 38.60, 39, 39.5, 40, 40.5, 41, 41.5, 42, 42.5, 43, 43.5, 44, 44.5, 45, 45.6 or 45.6. In this invention, in formulas II to III, a':b':c':d':e' can independently be specifically defined as 24.12:21.34:14.6:1.34:38.60, 25.60:13.63:13.61:1.56:45.60, 23.84:15.64:19.77:2.15:38.60, 21.35:25.94:12.35:1.76:38.60, 22.56:11.13:25.36:2.35:38.60, 21.52:7 .56:29.68:2.64:38.60, 23.60:4.32:30.98:2.50:38.60, 24.35:9.86:18.08:2.11:45.60, 25.31:6.27:21.36:1.46:45.60, 24.60:8.46:18.98:2.36:45.60, 24.35:7.56:20.04:2.45:45.60 or 24.86:7.86:19.12:2.56:45.60.In this invention, a':b':c':d':e' in Formula II is more preferably 24.12:21.34:14.6:1.34:38.60, 23.84:15.64:19.77:2.15:38.60, 21.35:25.94:12.35:1.76:38.60, 22.56:11.13:25.36:2.35:38.60, 21.52:7.56:29.68:2.64:38.60, 23.60:4.32:30.98:2.50:38.60. In this invention, a':b':c':d':e' in Formula III is more preferably 25.60:13.63:13.61:1.56:45.60, 24.35:9.86:18.08:2.11:45.60, 25.31:6.27:21.36:1.46:45.60, 24.60:8.46:18.98:2.36:45.60, 24.35:7.56:20.04:2.45:45.60, or 24.86:7.86:19.12:2.56:45.60.

[0028] In this invention, based on the total number of repeating units in the functionalized polydiene liquid rubber in the chain, the functionalization degree of the silicon-based functional groups is preferably 0.01~9.86%, more preferably 0.56~4.64%, and can specifically be 0.01%, 0.1%, 0.31%, 0.41%, 0.48%, 0.5%, 0.56%, 0.57%, 0.61%, 0.62%, 0.64%, 0.71%, 0.77%, 0.83%, 0.84%, 0.89%. 0.99%, 1%, 1.27%, 1.46%, 1.5%, 1.56%, 1.60%, 1.85%, 2%, 2.11%, 2.24%, 2.35%, 2.36%, 2.45%, 2.5%, 2.56%, 3%, 3.12%, 3.5%, 3.85%, 4%, 4.5%, 4.64%, 4.70%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5% or 9.86%. In this invention, the functionalization degree of the silicon-based functional group in Formula I is more preferably 0.31% to 4.7%, specifically 0.31%, 0.41%, 0.48%, 0.56%, 0.57%, 0.61%, 0.62%, 0.64%, 0.71%, 0.77%, 0.83%, 0.84%, 0.89%, 0.99%, 1.27%, 1.60%, 1.85%, 2.11%, 2.24%, 2.35%, 3.12%, 3.85%, 4.64%, or 4.70%. In this invention, the functionalization degree of Formula II is preferably 1.34% to 2.64%, specifically 1.34%, 1.76%, 2.15%, 2.35%, 2.50%, or 2.64%. In this invention, the functionalization degree of Formula III is preferably 1.46~2.56%, and can be specifically 1.46%, 1.56%, 2.11%, 2.36%, 2.45% or 2.56%.

[0029] In this invention, the number-average molecular weight of the functionalized polydiene liquid rubber in the chain is preferably 0.34 × 10⁻⁶. 4 ~10×10 4 g / mol, specifically 0.34 × 10 4 g / mol, 0.5×10 4 g / mol, 0.65×10 4 g / mol, 0.68×10 4 g / mol, 0.83×10 4 g / mol, 0.99×10 4 g / mol, 1×10 4 g / mol, 1.03×10 4 g / mol, 1.08×10 4g / mol、1.13×10 4 g / mol、1.12×10 4 g / mol、1.13×10 4 g / mol、1.14×10 4 g / mol、1.24×10 4 g / mol、1.26×10 4 g / mol、1.27×10 4 g / mol、1.29×10 4 g / mol、1.31×10 4 g / mol、1.32×10 4 g / mol、1.34×10 4 g / mol、1.38×10 4 g / mol、1.40×10 4 g / mol、1.45×10 4 g / mol、1.5×10 4 g / mol、1.56×10 4 g / mol、1.58×10 4 g / mol、1.63×10 4 g / mol、1.75×10 4 g / mol、1.78×10 4 g / mol、1.84×10 4 g / mol、1.89×10 4 g / mol、1.94×10 4 g / mol、1.95×10 4 g / mol、2×10 4 g / mol、2.15×10 4 g / mol、2.44×10 4 g / mol、2.5×10 4 g / mol、2.96×10 4 g / mol、3×10 4 g / mol、3.5×10 4 g / mol、4×10 4 g / mol、4.5×10 4 g / mol、5×10 4 g / mol、5.5×10 4 g / mol、6×10 4 g / mol、6.5×10 4 g / mol、7×10 4 g / mol、7.5×10 4g / mol or 7.56×10 4 g / mol. In this invention, the number-average molecular weight of Formula I is more preferably 0.65 × 10⁻⁶ g / mol. 4 ~2.96×10 4 g / mol, specifically 0.65 × 10 4 g / mol, 0.68×10 4 g / mol, 0.83×10 4 g / mol, 0.99×10 4 g / mol, 1.03×10 4 g / mol, 1.08×10 4 g / mol, 1.13×10 4 g / mol, 1.12×10 4 g / mol, 1.13×10 4 g / mol, 1.14×10 4 g / mol, 1.24×10 4 g / mol, 1.26×10 4 g / mol, 1.29×10 4 g / mol, 1.31×10 4 g / mol, 1.32×10 4 g / mol, 1.34×10 4 g / mol, 1.38×10 4 g / mol, 1.40×10 4 g / mol, 1.45×10 4 g / mol, 1.63×10 4 g / mol, 1.75×10 4 g / mol, 1.84×10 4 g / mol, 1.95×10 4 g / mol, 2.15×10 4 g / mol, 2.44×10 4 g / mol or 2.96×10 4 g / mol. In this invention, the number-average molecular weight of Formula II is more preferably 1.27~1.94×10 g / mol. 4 g / mol, specifically 1.27 × 10 4 g / mol, 1.56×10 4 g / mol, 1.58×10 4 g / mol, 1.78×10 4 g / mol, 1.89×10 4 g / mol or 1.94×10 4g / mol. In this invention, the number-average molecular weight of Formula III is more preferably 1.01~2.36×10 g / mol. 4 g / mol, specifically 1.01 × 10 4 g / mol, 1.79×10 4 g / mol, 1.84×10 4 g / mol, 1.89×10 4 g / mol, 2.01×10 4 g / mol or 2.36×10 4 g / mol.

[0030] In this invention, the molecular weight distribution index (PDI) of the in-chain functionalized polydiene liquid rubber is preferably 1.05 to 3.22, and can specifically be 1.05, 1.30, 1.35, 1.39, 1.46, 1.56, 1.59, 1.67, 1.68, 1.70, 1.76, 1.78, 1.79, 1.80, 1.82, 1.86, 1.88, 1.89, 1.90, 1.91, 1.92, 1.94, 1.95, 1.96, 2, 2.5, 3 or 3.22. In this invention, the molecular weight distribution index of Formula I is more preferably 1.30 to 3.22, specifically 1.30, 1.35, 1.39, 1.46, 1.56, 1.67, 1.68, 1.70, 1.78, 1.80, 1.82, 1.86, 1.88, 1.89, 1.90, 1.91, 1.92, 1.94, 1.95, 1.96, or 3.22. In this invention, the molecular weight distribution index of Formula II is more preferably 1.7 to 1.94, specifically 1.70, 1.76, 1.89, 1.90, or 1.94. In this invention, the molecular weight distribution index of Formula III is more preferably 1.56 to 1.96, specifically 1.56, 1.59, 1.68, 1.76, 1.79, or 1.96.

[0031] The present invention also provides a method for preparing the chain-functionalized polydiene liquid rubber described in the above technical solution, including method 1 and method 2.

[0032] In this invention, method 1 includes the following steps: mixing a solution of diene-based unsaturated rubber, a hydrosilylation reagent, and an olefin metathesis catalyst to carry out a modification reaction to obtain a chain-functionalized polydiene-based liquid rubber; the olefin metathesis catalyst includes a ruthenium-based olefin metathesis catalyst.

[0033] Unless otherwise specified, the materials and equipment used in this invention are all commercially available products in the field.

[0034] In this invention, the diene-based unsaturated rubber preferably comprises butadiene homopolymer or butadiene copolymer; the butadiene homopolymer preferably has at least one of cis-1,4-structural units, trans-1,4-structural units, and 1,2-structural units; the butadiene copolymer preferably comprises at least one of polybutadiene, butadiene-styrene copolymer, and butadiene-isoprene copolymer. In this invention, the number-average molecular weight of the diene-based unsaturated rubber is preferably 1 × 10⁻⁶. 4 ~10×10 4 g / mol, specifically 1×10 4 g / mol, 1.5×10 4 g / mol, 2×10 4 g / mol, 2.5×10 4 g / mol, 3×10 4 g / mol, 3.5×10 4 g / mol, 4×10 4 g / mol, 4.5×10 4 g / mol, 5×10 4 g / mol, 5.5×10 4 g / mol, 6×10 4 g / mol, 6.5×10 4 g / mol, 7×10 4 g / mol, 7.5×10 4 g / mol, 8×10 4 g / mol, 8.5×10 4 g / mol, 9×10 4 g / mol, 9.5×10 4 g / mol or 10×10 4 g / mol; the molecular weight distribution index of the diene unsaturated rubber is preferably 1.25~3.0, specifically 1.25, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9 or 3. In this invention, the polybutadiene preferably includes one or more of high-vinyl polybutadiene (denoted as PB1), high-cis polybutadiene (denoted as PB2), high-trans polybutadiene (denoted as PB3), and medium-cis polybutadiene (denoted as PB4); the 1,2-structure molar percentage content in the high-vinyl polybutadiene is preferably 97.09%; the high-cis polybutadiene... cis The preferred molar percentage of the -1,4-structure is 96.73%; the high trans-polybutadiene PB3 contains... transThe -1,4-structure molar percentage is preferably 96.68%; the 1,2-structure molar percentage in the medium cis-polybutadiene is preferably 10.34%. cis The preferred molar percentage of the -1,4- structure is 89.66%.

[0035] In this invention, the chemical formula of the hydrosilylation reagent is preferably Si(R1)(R2)(R3)H. In this invention, the definitions of R1, R2, and R3 in Si(R1)(R2)(R3)H are the same as the definitions of R1, R2, and R3 in -Si(R1)(R2)(R3). In this invention, the hydrosilylation reagent preferably includes trimethoxysilane, dimethoxymethylsilane, diethoxymethylsilane, dimethylmethoxysilane, dimethylethoxysilane, dimethoxyethylsilane, triphenylsilane, or dimethylphenylsilane. In this invention, the purity of the hydrosilylation reagent is preferably ≥97%.

[0036] In this invention, the molar ratio of C=C double bonds and hydrosilylation reagent in the diene unsaturated rubber is preferably 100:0~50, and can be specifically 100:5, 100:10, 100:15, 100:20, 100:25, 100:30, 100:35, 100:40, 100:45 or 100:50.

[0037] In this invention, the olefin metathesis catalyst includes ruthenium-based olefin metathesis catalysts, preferably including catalytically active species containing ruthenium-carbene structures, more preferably Grubbs-type ruthenium complexes, specifically at least one of generation I-III Grubbs catalysts, derivatives of generation I-III Grubbs catalysts, and supported ruthenium-based catalysts; the generation I-III Grubbs catalysts preferably include at least one of generation I Grubbs catalysts, generation II Grubbs catalysts, and generation III Grubbs catalysts; the derivatives of generation I-III Grubbs catalysts preferably include at least one of Hoveyda-Grubbs catalysts, chiral Grubbs catalyst derivatives, and ligand-modified derivatives; the supported ruthenium-based catalysts preferably include ruthenium-based catalysts supported on inorganic supports and organic supports.

[0038] In this invention, the molar ratio of the C=C double bond in the diene unsaturated rubber to the Grubbs catalyst is preferably 100:0.1~5, and can specifically be 100:0.1, 100:0.3, 100:0.5, 100:1, 100:1.5, 100:2, 100:2.5, 100:3, 100:3.5, 100:4, 100:4.5 or 100:5.

[0039] In this invention, the solvent in the diene-based unsaturated rubber solution preferably includes at least one of an aliphatic hydrocarbon solvent, an aromatic hydrocarbon solvent, a chlorinated hydrocarbon solvent, and tetrahydrofuran; the aliphatic hydrocarbon solvent preferably includes at least one of hexane, pentane, heptane, octane, and cyclohexane; the chlorinated hydrocarbon solvent preferably includes dichloromethane; the aromatic hydrocarbon solvent preferably includes at least one of benzene, toluene, xylene, ethylbenzene, chlorobenzene, and bromobenzene, and may specifically include at least one of toluene, n-hexane, dichloromethane, tetrahydrofuran, and benzene; the organic solvent is a dry organic solvent. In this invention, the concentration of the diene-based unsaturated rubber solution is preferably 0.01~0.2 g / mL, and may specifically be 0.01 g / mL, 0.05 g / mL, 0.08 g / mL, 0.1 g / mL, 0.12 g / mL, 0.15 g / mL, 0.18 g / mL, or 0.2 g / mL. In this invention, the diene-based unsaturated rubber solution is preferably obtained by dissolving the diene-based unsaturated rubber in an organic solvent. In this invention, the dissolution temperature is preferably room temperature, and the dissolution is preferably carried out under stirring conditions. The stirring speed is preferably 100~700 r / min, specifically 100 r / min, 200 r / min, 300 r / min, 400 r / min, 500 r / min, 600 r / min, or 700 r / min.

[0040] In this invention, the mixing of the diene unsaturated rubber solution, the hydrosilylation reagent, and the Grubbs catalyst preferably includes sequentially adding the hydrosilylation reagent and the Grubbs catalyst to the diene unsaturated rubber solution, or simultaneously adding the hydrosilylation reagent and the Grubbs catalyst to the diene unsaturated rubber solution.

[0041] In this invention, the temperature of the modification reaction is preferably 25~120℃, specifically 25℃, 30℃, 40℃, 50℃, 60℃, 70℃, 80℃, 90℃, 100℃, 110℃ or 120℃; the time of the modification reaction is preferably 0.5~10h, specifically 0.5h, 1h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h or 10h; the in-situ modification reaction is preferably carried out under anhydrous and oxygen-free conditions; the anhydrous and oxygen-free conditions preferably include at least one of nitrogen, helium and argon; the modification reaction is preferably carried out under stirring conditions, and the stirring speed is preferably 100~700r / min, specifically 100r / min, 200r / min, 300r / min, 400r / min, 500r / min, 600r / min or 700r / min.

[0042] After completing the modification reaction, the present invention preferably further includes: mixing the reaction system obtained from the modification reaction with a lower alcohol, allowing it to settle (oil phase-water phase separation), washing the resulting oil phase, and drying it to obtain a chain-functionalized polydiene liquid rubber. In this invention, the lower alcohol includes methanol and / or ethanol; the mass ratio of the diene unsaturated rubber to the volume of the lower alcohol is preferably 1g:50~200mL, specifically 1g:50mL, 1g:80mL, 1g:100mL, 1g:120mL, 1g:150mL, 1g:180mL, or 1g:200mL. The present invention does not have a special limitation on the oil phase-water phase separation; any separation method well known to those skilled in the art can be used, such as liquid-liquid separation or centrifugation. In this invention, the washing solvent preferably includes ethanol and / or methanol. The present invention does not have a special limitation on the drying conditions; drying to constant weight is sufficient.

[0043] In this invention, method 2 preferably includes the following steps: pre-reacting a Grubbs catalyst with a hydrosilylation reagent to obtain a pre-reaction mixture; mixing the pre-reaction mixture with a solution of diene-based unsaturated rubber to carry out a modification reaction to obtain a chain-functionalized polydiene-based liquid rubber; the olefin metathesis catalyst includes a ruthenium-based olefin metathesis catalyst.

[0044] In this invention, the temperature of the pre-reaction is preferably 25~120℃, specifically 25℃, 30℃, 40℃, 50℃, 60℃, 70℃, 80℃, 90℃, 100℃, 110℃ or 120℃; the time of the modification reaction is preferably 0.2~8h, specifically 0.2h, 1h, 2h, 3h, 4h, 5h, 6h, 7h or 8h; the pre-reaction is preferably carried out under anhydrous and oxygen-free conditions; the anhydrous and oxygen-free conditions preferably include at least one of nitrogen, helium and argon; the pre-reaction is preferably carried out under stirring conditions, and the stirring speed is preferably 100~700r / min, specifically 100r / min, 200r / min, 300r / min, 400r / min, 500r / min, 600r / min or 700r / min. In this invention, the pre-reaction can effectively suppress the metathesis reaction of olefins, reduce the formation of cyclized structures, and simultaneously achieve adjustable molecular weight and degree of hydrosilylation.

[0045] In this invention, the other preparation conditions in method 2 are the same as those in method 1, and will not be repeated here.

[0046] In this invention, the number-average molecular weight of the chain-functionalized polydiene liquid rubber prepared by method 1 is preferably 0.34 × 10⁻⁶. 4 ~7.56×10 4The molecular weight distribution index is preferably 1.05~3.20, and the degree of hydrosilylation is preferably 0~9.86%; the number average molecular weight of the chain-functionalized polydiene liquid rubber prepared by method 2 is preferably 0.45×10 g / mol. 4 ~5.76×10 4 The molecular weight distribution index is preferably 1.05~3.20 g / mol, and the degree of hydrosilylation is 0.41~2.11%.

[0047] The present invention uses method 2 to prepare in-chain functionalized polydiene liquid rubber, which is more conducive to suppressing the generation of cyclization byproducts and simultaneously achieving controllable molecular weight and degree of hydrosilylation.

[0048] The present invention also provides the application of the in-chain functionalized polydiene liquid rubber described in the above technical solution or the in-chain functionalized polydiene liquid rubber prepared by the preparation method described in the above technical solution in adhesives, coatings, sealants or composite materials.

[0049] To further illustrate the present invention, the following detailed description, in conjunction with embodiments, of the in-chain functionalized polydiene liquid rubber, its preparation method, and its applications, should not be construed as limiting the scope of protection of the present invention.

[0050] In the following embodiments: The high-vinyl polybutadiene PB1 contains 97.09% 1,2-structure molar percentage and has a number-average molecular weight of 3.77 × 10⁻⁶. 4 g / mol, with a molecular weight distribution index of 1.15.

[0051] High cis polybutadiene PB2 cis The -1,4-structure molar percentage content was 96.73%, and the number-average molecular weight was 0.86 × 10⁻⁶. 4 g / mol, with a molecular weight distribution index of 2.86.

[0052] High trans-polybutadiene PB3 trans The -1,4-structure molar percentage content was 96.68%, and the number-average molecular weight was 0.76 × 10⁻⁶. 4 g / mol, with a molecular weight distribution index of 1.17.

[0053] Medium cis-polybutadiene PB4 cis The molar percentage of the -1,4-structure was 89.66%, the molar percentage of the 1,2-structure was 10.34%, and the number-average molecular weight was 11.84 × 10⁻⁶. 4 g / mol, with a molecular weight distribution index of 1.93.

[0054] Butadiene-styrene copolymer: The molar percentage of butadiene is 61.4%, and the number average molecular weight is 3.50 × 10⁻⁶. 4 g / mol, with a molecular weight distribution index of 1.20.

[0055] Butadiene-isoprene copolymer: The molar percentage of butadiene is 54.4%, and the number average molecular weight is 3.98 × 10⁻⁶. 4 g / mol, with a molecular weight distribution index of 1.19.

[0056] Grubbs catalyst: The first generation Grubbs catalyst (Grubbs(I)): RuCl2(=CHPh)(PCy3)2, with a purity of 98%, is manufactured by Anaiji Chemical.

[0057] Second-generation Grubbs catalyst (Grubbs(II)): RuCl2(=CHPh)(PCy3)(IMes), purity 98%, Anaiji Chemical.

[0058] The third-generation Grubbs catalyst (Grubbs(III)): RuCl2(=CHPh)(IMes)(3-Br-Py)2, with a purity of 98%, is manufactured by Anaiji Chemical.

[0059] Unless otherwise specified, the temperature in the following examples is room temperature.

[0060] Example 1 Under nitrogen protection and at 400 r / min, an unsaturated polymer (high-vinyl polybutadiene PB1) was dissolved in dry toluene to obtain reaction solution A. A hydrosilylation reagent (trimethoxysilane) and Grubbs(II) catalyst were added to solution A to obtain reaction solution B. Solution B was reacted at 80 °C for 5 h, ethanol was added, the mixture was allowed to settle, filtered, and the resulting oil phase was washed with ethanol and dried to constant weight to obtain a chain-functionalized polybutadiene liquid rubber (Formula I). ​​The concentration of the unsaturated polymer in reaction solution A was 0.1 g / mL, and the molar ratio of C=C double bonds, hydrosilylation reagent, and Grubbs(II) in the unsaturated polymer was 100:20:0.5. The ratio of unsaturated polymer to ethanol used for sedimentation was 1 g:100 mL.

[0061] Example 2 The only difference from Example 1 is that the unsaturated polymer is high-cis polybutadiene PB2.

[0062] Example 3 The only difference from Example 1 is that the unsaturated polymer is high trans-polybutadiene PB3.

[0063] As shown in Examples 1-3, under the Grubbs catalyst, polybutadiene with different microstructures can undergo hydrosilylation. The hydrosilylation efficiency of high vinyl polybutadiene rubber PB1 is significantly higher than that of high cis structure PB2 and high trans structure polybutadiene PB3, indicating that the hydrosilylation reaction tends to occur at the side vinyl position of the polymer chain.

[0064] Example 4 The only difference from Example 1 is that the molar ratio of C=C double bonds, hydrosilylation reagent and Grubbs(II) in the unsaturated polymer is 100:5:0.5.

[0065] Example 5 The only difference from Example 1 is that the molar ratio of C=C double bonds, hydrosilylation reagent and Grubbs(II) in the unsaturated polymer is 100:10:0.5.

[0066] Example 6 The only difference from Example 1 is that the molar ratio of C=C double bonds, hydrosilylation reagent and Grubbs(II) in the unsaturated polymer is 100:15:0.5.

[0067] Example 7 The only difference from Example 1 is that the molar ratio of C=C double bonds, hydrosilylation reagent and Grubbs(II) in the unsaturated polymer is 100:20:1.0.

[0068] Example 8 The only difference from Example 1 is that the molar ratio of C=C double bonds, hydrosilylation reagent and Grubbs(II) in the unsaturated polymer is 100:20:1.5.

[0069] Example 9 The only difference from Example 1 is that the molar ratio of C=C double bonds, hydrosilylation reagent and Grubbs(II) in the unsaturated polymer is 100:20:3.0.

[0070] Comparative Example 1 The only difference from Example 1 is that the reaction temperature is 20°C.

[0071] Example 10 The only difference from Example 1 is that the reaction temperature is 40°C.

[0072] Example 11 The only difference from Example 1 is that the reaction temperature is 60°C.

[0073] Example 12 The only difference from Example 1 is that the reaction temperature is 100°C.

[0074] Example 13 The only difference from Example 1 is that the Grubbs(II) catalyst is replaced with Grubbs(I).

[0075] Example 14 The only difference from Example 1 is that the Grubbs(II) catalyst is replaced with Grubbs(III).

[0076] Example 15 The only difference from Example 1 is that the hydrosilylation agent is triethoxysilane.

[0077] Example 16 The only difference from Example 1 is that the hydrosilylation agent is dimethoxymethylsilane.

[0078] Example 17 The only difference from Example 1 is that the hydrosilylation agent is diethoxymethylsilane.

[0079] Comparative Example 2 The only difference from Example 1 is that no hydrosilylation reagent was added.

[0080] Example 18 Under nitrogen protection and at 400 r / min, an unsaturated polymer (high-vinyl polybutadiene PB1) was dissolved in dry toluene to obtain reaction solution A. A hydrosilylation reagent (trimethoxysilane), Grubbs(II) catalyst, and dry toluene were mixed and pre-reacted at 80 °C for 0.5 h to obtain reaction solution B. Reaction solution B was then added to reaction solution A and reacted at 80 °C for 5 h. Ethanol was added, the mixture was allowed to settle, filtered, and the resulting oil phase was washed with ethanol and dried to constant weight to obtain a chain-functionalized polybutadiene liquid rubber. The concentration of the unsaturated polymer in reaction solution A was 0.1 g / mL, and the molar ratio of C=C double bonds, hydrosilylation reagent, and Grubbs(II) in the unsaturated polymer was 100:20:0.5. The volume ratio of toluene in reaction solution A to that in reaction solution B was 10:1. The ratio of unsaturated polymer to ethanol used for sedimentation was 1 g:100 mL.

[0081] Example 19 The only difference from Example 18 is that the pre-reaction time is 1 hour.

[0082] Example 20 The only difference from Example 18 is that the pre-reaction time is 2 hours.

[0083] Example 21 The only difference from Example 18 is that the pre-reaction time is 3 hours.

[0084] Example 22 The only difference from Example 18 is that the pre-reaction time is 5 hours.

[0085] Examples 18-22 show that the longer the pre-reaction time of trimethoxysilane and Grubbs(II), the higher the retention ratio of the 1,2-structure in the polymer and the lower the content of the cyclized structure, indicating that the main chain structure is closer to the original unsaturated polymer and the olefin metathesis reaction is inhibited. However, due to the thermal decomposition of the hydrosilylation active material during the pretreatment at 80°C, it can be seen that the hydrosilylation efficiency gradually decreases and the molecular weight gradually increases with the increase of the pretreatment time.

[0086] Example 23 The only difference from Example 18 is that the pre-reaction temperature is 100°C.

[0087] Example 24 The only difference from Example 18 is that the hydrosilylation reagent used in the pre-reaction is triethoxysilane.

[0088] Example 25 The only difference from Example 18 is that the hydrosilylation agent used in the pre-reaction is dimethoxymethylsilane.

[0089] Example 26 The only difference from Example 18 is that the hydrosilylation reagent used in the pre-reaction is diethoxymethylsilane.

[0090] Example 27 The only difference from Example 18 is that the unsaturated polymer is a butadiene-styrene copolymer, resulting in a liquid rubber of butadiene-styrene copolymer with functionalized chain (Formula II).

[0091] Example 28 The only difference from Example 18 is that the unsaturated polymer is butadiene-isoprene copolymer, resulting in a liquid butadiene-isoprene copolymer liquid rubber (Formula III) with functionalized chain.

[0092] Example 29 The only difference from Example 1 is that the unsaturated polymer is butadiene-styrene copolymer, resulting in a liquid rubber of butadiene-styrene copolymer with functionalized chain (Formula II).

[0093] Example 30 The only difference from Example 1 is that the unsaturated polymer is butadiene-styrene copolymer, the reaction temperature is 50°C, and a liquid rubber of butadiene-styrene copolymer with functionalized chain is obtained (Formula II).

[0094] Example 31 The only difference from Example 1 is that the unsaturated polymer is butadiene-styrene copolymer; the molar ratio of C=C double bond, trimethoxysilane and Grubbs(II) in the polybutadiene-styrene copolymer substrate is 100:20:1.0, resulting in a liquid rubber of chain-functionalized butadiene-styrene copolymer (Formula II).

[0095] Example 32 The only difference from Example 1 is that the unsaturated polymer is butadiene-styrene copolymer; the molar ratio of C=C double bond, trimethoxysilane and Grubbs(II) in the polybutadiene-styrene copolymer substrate is 100:20:1.5, resulting in a liquid rubber of in-chain functionalized butadiene-styrene copolymer (Formula II).

[0096] Example 33 The only difference from Example 1 is that the unsaturated polymer is butadiene-styrene copolymer; the hydrosilylation agent is triethoxysilane, resulting in a liquid rubber of butadiene-styrene copolymer with functionalized chain (Formula II).

[0097] Example 34 The only difference from Example 1 is that the unsaturated polymer is butadiene-isoprene copolymer, resulting in a liquid butadiene-isoprene copolymer liquid rubber (Formula III) with functionalized chain.

[0098] Example 35 The only difference from Example 1 is that the unsaturated polymer is butadiene-isoprene copolymer, the reaction temperature is 50°C, and the resulting liquid butadiene-isoprene copolymer liquid rubber (Formula III) is obtained with functionalized liquid butadiene-isoprene copolymer in the chain.

[0099] Example 36 The only difference from Example 1 is that the unsaturated polymer is a butadiene-isoprene copolymer; the molar ratio of C=C double bond, hydrosilylation agent and Grubbs(II) in the unsaturated polymer is 100:20:1.0, resulting in a liquid butadiene-isoprene copolymer liquid rubber (Formula III) with functionalized chain.

[0100] Example 37 The only difference from Example 1 is that the unsaturated polymer is a butadiene-isoprene copolymer; the ratio of C=C double bond, hydrosilylation agent and Grubbs(II) in the unsaturated polymer is 100:20:1.5, resulting in a liquid butadiene-isoprene copolymer liquid rubber (Formula III) with functionalized chain.

[0101] Example 38 The only difference from Example 1 is that the unsaturated polymer is butadiene-isoprene copolymer; the hydrosilylation agent is triethoxysilane, resulting in a liquid butadiene-isoprene copolymer liquid rubber (Formula III) with functionalized chain.

[0102] Example 39 The only difference from Example 1 is that the reaction substrate is medium cis polybutadiene rubber PB4.

[0103] Test Example 1 The microstructure and hydrosilylation efficiency of in-chain functionalized polydiene liquid rubber were determined by 1H NMR spectroscopy. 1 H NMR and 13 Calculation by C NMR measurement.

[0104] Number average molecular weight of in-chain functionalized polydiene liquid rubbers M n The molecular weight distribution (PDI) was determined by gel permeation chromatography (GPC).

[0105] Figure 1 The image shows the hydrogen spectrum of the chain-functionalized polybutadiene liquid rubber prepared in Example 1. Figure 2 The carbon spectrum of the chain-functionalized polybutadiene liquid rubber prepared in Example 1 is shown below. Figures 1-2 It can be seen that the trimethoxy group was successfully introduced into the polybutadiene backbone, resulting in a liquid rubber of polybutadiene with in-chain functionalization.

[0106] Figure 3 The 1H NMR spectra of the chain-functionalized polybutadiene liquid rubbers prepared in Examples 1, 4-6 and Comparative Example 2 show that, under the condition of keeping the catalyst concentration constant, the functionalization degree of the target product gradually increases by increasing the amount of hydrosilylation reagent added, specifically from 0.56% to 2.11%.

[0107] Figure 4 The microstructure content diagrams of the chain-functionalized polybutadiene liquid rubbers prepared in Examples 1 and 7-9 show that when the concentration of the hydrosilylation reagent remains constant, the hydrosilylation efficiency is positively correlated with the amount of catalyst, and the efficiency increases from 2.11% to 4.64% as the amount of catalyst increases.

[0108] Table 1. Test results of the in-chain functionalized polybutadiene liquid rubber (Formula I) prepared in Examples 1-18, Example 39 and Comparative Examples 1-2

[0109] Table 1 shows that by adjusting the types of reaction substrates and hydrosilylation reagents, the amounts of catalysts and hydrosilylation reagents, and experimental parameters such as temperature, mid-chain functionalized liquid polybutadiene rubber with controllable molecular weight and degree of hydrosilylation can be obtained. In Comparative Example 1, the reaction temperature was too low, and the hydrosilylation reaction could not proceed.

[0110] Figure 5 The graph shows the molecular weight variation of the chain-functionalized polybutadiene liquid rubbers prepared in Examples 1 and 18-22. As can be seen from the graph, by extending the pre-reaction time of the catalyst and hydrosilylation reagent, the olefin metathesis reaction can be effectively suppressed, the original skeletal structure of polybutadiene can be better preserved, and a product with a higher molecular weight can be obtained.

[0111] Table 2. Test results of the in-chain functionalized polybutadiene liquid rubbers prepared in Examples 18-26

[0112] As shown in Table 2, by changing the pre-reaction temperature and time, and the type of hydrosilylation reagent, liquid polybutadiene rubber with diverse functional groups and adjustable molecular weight can be obtained.

[0113] Table 3. Test results of the in-chain functionalized polydiene liquid rubbers (Formula II and Formula III) prepared in Examples 27-38

[0114] As shown in Table 3, the in-chain functionalized polydiene liquid rubbers of Formula II and Formula III prepared in Examples 27-38 all achieved effective introduction of the target functional groups into the middle segment of the molecular chain, with functionalization efficiencies reaching 1.34-2.64%. By changing reaction parameters, such as catalyst dosage, reaction temperature, and type of hydrosilylation reagent, the molecular weight and hydrosilylation efficiency of the polydiene can be precisely controlled, demonstrating that this preparation process has broad applicability to in-chain functionalization reactions of unsaturated rubbers.

[0115] Figure 6 The diagram shows the change in water contact angle of the liquid rubber prepared in Example 1(ii) and Comparative Example 2(i), by... Figure 6 It can be seen that the introduction of polar groups leads to significant changes in the surface properties of the polymer. Compared with the unfunctionalized liquid rubber prepared in Comparative Example 2, the water contact angle of the functionalized liquid rubber decreased from 95.0° to 92.8°, indicating that the surface properties of polydiene liquid rubber were significantly improved after in-chain functionalization.

[0116] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A chain-functionalized polydiene liquid rubber, wherein the main chain comprises a polydiene molecular chain and the side chains contain silicon-based functional groups; Based on the total number of repeating units of the functionalized polydiene liquid rubber in the chain, the degree of functionalization of the silicon-based functional groups is 0.01~9.86%.

2. The in-chain functionalized polydiene liquid rubber according to claim 1, characterized in that, The polydiene molecular chain includes diene homopolymer molecular chains or diene copolymer molecular chains; The diene homopolymer molecular chain has at least one of cis-1,4-structural units, trans-1,4-structural units, and 1,2-structural units; the diene copolymer molecular chain includes at least one of polybutadiene molecular chain, polyisoprene molecular chain, butadiene-styrene copolymer molecular chain, and butadiene-isoprene copolymer molecular chain.

3. The in-chain functionalized polydiene liquid rubber according to claim 1, characterized in that, The silicon-based functional group has the structural formula -Si(R1)(R2)(R3), wherein R1, R2 and R3 are independently hydrogen, alkyl, alkoxy or aryl, and at least one of R1, R2 and R3 is alkoxy.

4. The in-chain functionalized polydiene liquid rubber according to claims 1-3, characterized in that, The functionalized polydiene liquid rubber in the chain has a cyclic structure, which includes five-membered rings and / or six-membered rings; the cyclic structure accounts for 0 to 80% of the total structural units of the molecular chain.

5. The in-chain functionalized polydiene liquid rubber according to claim 4, characterized in that, The number-average molecular weight of the functionalized polydiene liquid rubber in the chain is 0.34 × 10⁻⁶. 4 ~7.56×10 4 g / mol, with a molecular weight distribution index of 1.05~3.

22.

6. The in-chain functionalized polydiene liquid rubber according to claim 1, 2, 3 or 5, characterized in that, The functionalized polydiene liquid rubber in the chain has a structure shown in any one of formulas I to III: Formula I; Formula II; Formula III; Wherein, R1, R2 and R3 are independently hydrogen, alkyl, alkoxy or aryl, and at least one of R1, R2 and R3 is alkoxy; X has any of the following structures: ; In Equation I, taking a'+b'+c'+d'=100 as an example, a'=2.73~95.91, b'=0~73.89, c'=2.33~83.17, and d'=0~4.70; In formulas II to III, taking a'+b'+c'+d'+e'=100 as an example, a'=21.35~25.60, b'=4.32~25.94, c'=12.35~30.98, d'=1.34~2.64, and e'=38.60~45.

60.

7. A method for preparing the chain-functionalized polydiene liquid rubber according to any one of claims 1 to 6, comprising method 1 and method 2; Method 1 includes the following steps: A solution of diene-based unsaturated rubber, a hydrosilylation reagent, and an olefin metathesis catalyst are mixed and subjected to a modification reaction to obtain a chain-functionalized polydiene-based liquid rubber. Method 2 includes the following steps: pre-reacting an olefin metathesis catalyst with a hydrosilylation reagent to obtain a pre-reaction mixture; mixing the pre-reaction mixture with a solution of diene unsaturated rubber to carry out a modification reaction to obtain a chain-functionalized polydiene liquid rubber. The olefin metathesis catalyst includes ruthenium-based olefin metathesis catalysts.

8. The preparation method according to claim 7, characterized in that, In methods 1 and 2: The diene-based unsaturated rubber includes butadiene homopolymer or butadiene copolymer; the butadiene homopolymer has at least one of cis-1,4-structural units, trans-1,4-structural units and 1,2-structural units; the butadiene copolymer includes at least one of polybutadiene, butadiene-styrene copolymer and butadiene-isoprene copolymer. The chemical formula of the hydrosilylation reagent is SiH(R1)(R2)(R3); The molar ratio of C=C double bonds to hydrosilylation reagent in the diene-based unsaturated rubber is 100:0.01~50; The molar ratio of C=C double bonds and olefin metathesis catalyst in the diene unsaturated rubber is 100:0.1~5; The number-average molecular weight of the diene-based unsaturated rubber is 1×10⁻⁶. 4 ~15×10 4 g / mol, with a molecular weight distribution index of 1.25~3.0; The solvent in the diene unsaturated rubber solution includes at least one of aliphatic hydrocarbon solvents, aromatic hydrocarbon solvents, chlorinated hydrocarbon solvents, and tetrahydrofuran; The modification reaction is carried out at a temperature of 25~120℃ for a time of 0.5~10h; the in-situ modification reaction is carried out under anhydrous and oxygen-free conditions.

9. The preparation method according to claim 7, characterized in that, In Method 2, the pre-reaction temperature is 25~120℃ and the time is 0.2~8h; the pre-reaction is carried out under anhydrous and oxygen-free conditions.

10. The use of the in-chain functionalized polydiene liquid rubber according to any one of claims 1 to 6 or the in-chain functionalized polydiene liquid rubber prepared by the preparation method according to any one of claims 7 to 9 in adhesives, coatings, sealants or composite materials.

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