A polymer, its preparation and use

Abstract

The application provides a polymer and a preparation method and use thereof, and belongs to the field of polyurea thermoplastic elastomers. The polymer has a polysiloxane-polyurea and a polyether-polyurea structure, and is used as a compatibilizer when mixed with polysiloxane-polyurea and polyether-polyurea to prepare a thermoplastic elastomer. The polymer makes the prepared elastomer have weather resistance, hydrophobicity, temperature resistance and flexibility of polysiloxane, and high strength and high modulus of polyurea, and has excellent comprehensive performance.

Description

[0001] This application is a divisional application based on the parent application No. 202310220297.1, entitled "A Novel Three-Component Blend Polyurea Thermoplastic Elastomer and Its Preparation Method Thereof", filed on March 9, 2023. Technical Field

[0002] This invention relates to the field of polyurea thermoplastic elastomers, and more particularly to a polymer, its preparation method, and its uses. Background Technology

[0003] Polyurea thermoplastic elastomers are block polymers formed by the reaction of isocyanate compounds and amino compounds. They consist of two parts: hard segments and soft segments. The properties of the elastomer can be controlled by adjusting the molecular structure and ratio of the soft and hard segments. Polysiloxanes are typical flexible segments and can be used as the soft segment component of polyurea elastomers to improve certain properties of traditional polyureas, such as hydrophobicity, weather resistance, and low-temperature resistance. Therefore, polysiloxane-modified polyurea thermoplastic elastomers have always been a research hotspot.

[0004] Currently, there are two methods for introducing polysiloxanes into polyureas. One is to use polysiloxanes alone as soft segments, and we name the polyurea prepared in this way as polysiloxane-polyurea. The other is to mix polysiloxanes with traditional amine-terminated polyethers as soft segments, and we name the polyurea prepared in this way as polysiloxane-modified polyurea.

[0005] Patent CN102428117B reports a polyether-polyurea synthesized using terminal amine polyether, polyether diol with a molecular weight less than 500 g / mol, and diisocyanate, achieving a tensile strength of up to 27 MPa. However, completely replacing polyether with polysiloxane as the soft segment, or introducing a mixture of polysiloxane and polyether as the soft segment, results in a polyurea with lower strength than that obtained using only polyether as the soft segment. Natascha et al. synthesized polysiloxane-polyurea via a two-step method using terminal aminopropyl polysiloxane, 1,3-bis(aminopropyl)-tetramethyldisiloxane, and dicyclohexylmethane diisocyanate as raw materials with molecular weights of 3000-9000 g / mol. This polysiloxane-polyurea exhibits good physiological inertness and hydrophobicity, but its 100% elongation modulus is only 0.2–2 MPa, and its tensile strength is only 1–6 MPa (Reference: Natascha Riehle, et al. European Polymer Journal, 2018, 101, 190-201.), indicating relatively poor mechanical properties. Patent CN112980302B discloses a polysiloxane-polyurea synthesized using a conventional method. This polyurea is synthesized from raw materials such as terminal amino-based polysiloxanes with a molecular weight of 500–10000 g / mol, isophorone diisocyanate, and triaminobenzene, exhibiting a tensile strength of 0.02–2.5 MPa. While retaining the good hydrophobicity of polysiloxanes, the material strength is very low. Patent CN1764684 discloses a linear polyurea prepared from amino-based polysiloxanes, a series of aliphatic diisocyanates, and polyether polyols, with a maximum strength not exceeding 7 MPa. Patent CN112794975A ​​uses hydroxyl-terminated polysiloxanes and amino-based polyethers as soft segments, small-molecule polyols as chain extenders, and silane coupling agents as crosslinking agents to prepare polysiloxane-modified polyurethane urea. This method overcomes, to some extent, the low strength of polysiloxanes and the poor weather resistance of polyethers, achieving a tensile strength of 22 MPa. However, compared to traditional polyether-polyurea, its strength is still insufficient, and due to the introduction of silane coupling agents for chemical cross-linking, the material does not have thermoplasticity and cannot be further processed.

[0006] In summary, there are currently two main technical routes for silicone-modified polyurea: one is to use hydroxyl or amino polysiloxanes alone as soft segments, and the other is to mix polysiloxanes with polyethers as soft segments. The preparation technology still follows the traditional preparation technology of polyurea thermoplastic elastomers.

[0007] Based on the problems existing in the prior art, there are technical problems that urgently need to be solved, such as the poor compatibility between polysiloxane and polyether, and the inability of the elastomer prepared after mixing with polyurea to simultaneously possess comprehensive properties such as flexibility and high strength. Summary of the Invention

[0008] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0009] This invention provides a polymer selected from one of the general formulas (III), (IV), (V), and (VI):

[0010]

[0011]

[0012] Where q is independently selected from integers greater than 1 and less than or equal to 4; p and s are independently selected from integers from 2 to 4; o is independently selected from integers from 50 to 100;

[0013] In the general formula, I represents polysiloxane-polyurea, and the structure of formula I is as follows:

[0014]

[0015] In the general formula, II stands for polyether-polyurea, and the structure of formula II is as follows:

[0016]

[0017] Wherein, n and r are independently selected from integers from 15 to 65; m and m′ are independently selected from integers from 50 to 100; X is independently selected from one of the dicyclohexylmethane diisocyanate segment, diphenylmethane diisocyanate segment, hexamethylene diisocyanate segment, and toluene diisocyanate segment; Y is independently selected from one of (CH2)4, (CH2)5, (CH2)6, CH2CH2CH3, and CH2CH2CH2.

[0018] Furthermore, q is 2 or 3.

[0019] Furthermore, p and s are independently taken from 3 or 4.

[0020] Furthermore, o is an independent integer selected from 55 to 95.

[0021] Furthermore, o is an independent integer selected from 60 to 90.

[0022] Furthermore, n and r are independently selected from integers between 20 and 60.

[0023] Furthermore, n and r are independent integers selected from 25 to 55.

[0024] Furthermore, m and m′ are independently selected from integers between 55 and 95.

[0025] Furthermore, m and m′ are independently selected from integers between 60 and 90.

[0026] Furthermore, X is independently selected from one of the dicyclohexylmethane diisocyanate segment, diphenylmethane diisocyanate segment, and toluene diisocyanate segment.

[0027] Furthermore, Y is independently selected from one of (CH2)4, CH2CH2CH3 and CH2CH2CH2.

[0028] The present invention also provides a method for preparing the above-mentioned polymer, comprising the following steps:

[0029] (1) The diisocyanate compound and the terminal aminopropyl polysiloxane were mixed in a solvent and reacted. Compound N was added to the reaction product and the reaction was continued to obtain polymer-1.

[0030] (2) The diisocyanate compound and the terminal amine polyether were mixed in a solvent and reacted. Compound N was added to the reaction product and the reaction was continued to obtain polymer-2.

[0031] The compound N is independently selected from one or more of chain extender E, end capping agent F, chain extender G, chain extender H and chain extender I;

[0032] (3) Polymer-1, polymer-2 and catalyst are mixed and reacted to obtain polymer;

[0033] The chain extender E is selected from one or more of NH2(CH2)4NH2, NH2(CH2)5NH2, NH2(CH2)6NH2 and NH2CH2CH(CH3)CH2CH2CH2NH2;

[0034] The end-capping agent F is selected from one or more of CH3(CH2)2NH2, CH3(CH2)3NH2, CH3(CH2)4NH2 and CH3(CH2)5NH2;

[0035] The chain extender G has the general formula shown in formula (IX):

[0036]

[0037] Where p is an independent integer taken from 2 to 4;

[0038] The chain extender H has the general formula shown in formula (X):

[0039]

[0040] Where q is independently taken from integers greater than 1 and less than or equal to 4;

[0041] The chain extender I has the general formula shown in formula (XI):

[0042]

[0043] Where s is an independent integer taken from 2 to 4.

[0044] Furthermore, when compound N includes chain extender E and chain extender G, the structural formula of the polymer is selected from one of the general formulas shown in formulas (III) and (IV).

[0045] Furthermore, when compound N includes chain extender E and chain extender H, the structural formula of the polymer is selected from the general formula shown in formula (V).

[0046] Furthermore, when compound N includes chain extender E and chain extender I, the structural formula of the polymer is selected from the general formula shown in formula (VI).

[0047] Furthermore, the chain extender E is selected from one or more of NH2(CH2)4NH2, NH2(CH2)5NH2 and NH2(CH2)6NH2.

[0048] Furthermore, the chain extender E is selected from NH2(CH2)4NH2 and / or NH2(CH2)5NH2.

[0049] Furthermore, the end-capping agent F is selected from one or more of CH3(CH2)3NH2, CH3(CH2)4NH2 and CH3(CH2)5NH2.

[0050] Furthermore, the capping agent F is CH3(CH2)3NH2 and / or CH3(CH2)5NH2.

[0051] Furthermore, the chain extender G has the general formula shown in formula (IX):

[0052]

[0053] Where p is 3 or 4.

[0054] Furthermore, the chain extender H has the general formula shown in formula (X):

[0055]

[0056] Where q is 2 or 3.

[0057] Furthermore, the chain extender I has the general formula shown in formula (XI):

[0058]

[0059] Where s is 3 or 4.

[0060] Furthermore, in step (1) and / or step (2), the solvent independently comprises one or more of N,N-dimethylformamide, acetone, tetrahydrofuran, isopropanol, n-hexane, toluene, and cyclohexane.

[0061] Further, the solvent is a mixed solvent of toluene and acetone, or a mixed solvent of n-hexane and acetone, or a mixed solvent of n-hexane and tetrahydrofuran, or a mixed solvent of cyclohexane and tetrahydrofuran, or a mixed solvent of toluene and isopropanol, or a mixed solvent of cyclohexane and isopropanol.

[0062] Further, in step (1) and / or step (2), the diisocyanate compound independently includes one or more of dicyclohexylmethane diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate and toluene diisocyanate.

[0063] Furthermore, the diisocyanate compound is one or more of dicyclohexylmethane diisocyanate, diphenylmethane diisocyanate, and hexamethylene diisocyanate.

[0064] Furthermore, the diisocyanate compound is dicyclohexylmethane diisocyanate.

[0065] Furthermore, the terminal aminopropyl polysiloxane has the general formula shown in formula (VII):

[0066]

[0067] Where n is an integer selected from 15 to 65;

[0068] The terminal amine polyether has the general formula shown in formula (VIII):

[0069]

[0070] Where r is selected from integers from 15 to 65.

[0071] Furthermore, n is selected from integers between 20 and 60.

[0072] Furthermore, n is selected from integers between 25 and 55.

[0073] Furthermore, r is selected from integers between 15 and 65.

[0074] Furthermore, r is selected from integers between 20 and 60.

[0075] Furthermore, r is selected from integers between 25 and 55.

[0076] Furthermore, the catalyst is stannous isooctanoate or dibutyltin dilaurate.

[0077] Further, in step (1), the mass ratio of the diisocyanate compound, terminal aminopropyl polysiloxane, solvent and compound N is (3-26):(6-70):(70-400):(0.5-9).

[0078] Further, in step (1), the mass ratio of the diisocyanate compound, terminal aminopropyl polysiloxane, solvent and compound N is (5-24):(10-65):(80-380):(0.8-8).

[0079] Further, in step (1), the mass ratio of the diisocyanate compound, terminal aminopropyl polysiloxane, solvent and compound N is (7-22):(15-60):(100-350):(1-7).

[0080] Further, in step (2), the mass ratio of the diisocyanate compound, the terminal amine polyether, the solvent, and compound N is (5-65):(22-165):(120-1000):(0.5-20).

[0081] Further, in step (2), the mass ratio of the diisocyanate compound, the terminal amine polyether, the solvent and compound N is (10-60):(25-160):(150-900):(1-19).

[0082] Further, in step (2), the mass ratio of the diisocyanate compound, the terminal amine polyether, the solvent and compound N is (15-55):(30-150):(180-800):(2-18).

[0083] Further, in step (3), the molar ratio of polymer-1 to polymer-2 is 1:(1.5 to 5.0).

[0084] Furthermore, when the polymer has the structural formula (Ⅲ), the molar ratio of polymer-1 to polymer-2 is 1:2;

[0085] When the structural formula of the polymer is formula (Ⅳ), the molar ratio of polymer-1 and polymer-2 is 1:4;

[0086] When the polymer has the structural formula (V) or (VI), the molar ratio of polymer-1 to polymer-2 is 1:(1.5 to 5.0).

[0087] Furthermore, in step (3), the amount of catalyst added is 0.05% to 0.5% of the total mass of the system.

[0088] Furthermore, in steps (1) and (2), the reaction temperature is independently 20-30℃ and the reaction time is independently 10-30min; in step (3), the reaction temperature is 50-110℃ and the reaction time is 8-24h.

[0089] Furthermore, in steps (1) and (2), the reaction temperature is 25°C.

[0090] Furthermore, in steps (1) and (2), the reaction time is 15 to 25 minutes.

[0091] Furthermore, in steps (1) and (2), the reaction time is 20 minutes.

[0092] Furthermore, in step (3), the reaction temperature is 60–100°C.

[0093] Furthermore, in step (3), the reaction temperature is 70–90°C.

[0094] Furthermore, in step (3), the reaction time is 10 to 22 hours.

[0095] Furthermore, in step (3), the reaction time is 12 to 20 hours.

[0096] The present invention also provides a compatibilizer comprising the polymer described above.

[0097] The present invention also provides a thermoplastic elastomer, wherein the thermoplastic elastomer is composed of 20 to 70 parts of polysiloxane-polyurea of ​​Formula I, 30 to 80 parts of polyether-polyurea of ​​Formula II and 3 to 20 parts of the above-mentioned polymer, wherein the content of hard segments in the polysiloxane-polyurea and the polyether-polyurea is independently 15 to 50 wt%, and the R value is independently 0.98 to 1.02.

[0098] Further, the mass fraction of the polysiloxane-polyurea represented by Formula I is preferably 25-65 parts, more preferably 30-60 parts; the mass fraction of the polyether-polyurea represented by Formula II is preferably 35-75 parts, more preferably 40-70 parts; the mass fraction of the polymer is preferably 5-18 parts, more preferably 7-16 parts; the hard segment content in the polysiloxane-polyurea and polyether-polyurea is preferably 20-45 wt%, more preferably 25-40 wt%; and the R value is preferably 0.99-1.01.

[0099] Furthermore, the tensile strength of the thermoplastic elastomer is 15 MPa, or 16.5 MPa, or 19.8 MPa, or 20.31 MPa, or 24.69 MPa, or 31.65 MPa, or 50.4 MPa;

[0100] The elongation at break is 121%, or 380%, or 471%, or 486%, or 780%, or 806%, or 820%;

[0101] The 5% thermal weight loss temperature is 315℃;

[0102] The water contact angle is 110.4° or 108.3°;

[0103] The water absorption rate after soaking in water for 40 days at room temperature is 1.27% or 2.14%.

[0104] It has two glass transition temperatures: -123℃ and -62℃.

[0105] The present invention also provides a method for preparing the above-mentioned thermoplastic elastomer, wherein 20-70 parts of polysiloxane-polyurea of ​​Formula I, 30-80 parts of polyether-polyurea of ​​Formula II and 3-20 parts of the above-mentioned polymer are mixed in a solvent and then dried to obtain the thermoplastic elastomer.

[0106] Furthermore, the solvent comprises one or more of N,N-dimethylformamide, acetone, tetrahydrofuran, isopropanol, n-hexane, toluene, and cyclohexane.

[0107] Furthermore, the amount of solvent used is 3 to 8 times the total mass of the system.

[0108] Furthermore, the amount of solvent used is 4 to 7 times the total mass of the system.

[0109] Furthermore, the amount of solvent used is 5 or 6 times the total mass of the system.

[0110] Furthermore, the drying temperature is 50℃ and the drying time is 24 hours.

[0111] The beneficial effects of this invention are:

[0112] (1) The present invention introduces a method for preparing a polymer blend system, thereby obtaining a thermoplastic elastomer. This solves the technical problems in the prior art, such as the poor compatibility between polysiloxane and polyether, and the inability of the elastomer prepared after mixing with polyurea to simultaneously possess comprehensive properties such as flexibility and high strength. Through the preparation method of the present invention, the elastomer simultaneously possesses the weather resistance, hydrophobicity, temperature resistance and flexibility of polysiloxane, as well as the high strength and high modulus of polyurea, resulting in excellent comprehensive performance.

[0113] (2) Unlike common melt blending methods, this invention uses solution blending, which can be completed at room temperature without the need for complex heating equipment. Based on the compatibilizing effect of polymer compatibilizers, the blends have a thermodynamically stable structure, avoiding the defects of melt blending. Detailed Implementation

[0114] Terminology Explanation:

[0115] Polysiloxane-polyurea: Polyurea prepared using only amino-based polysiloxanes as soft segments.

[0116] Polyether-polyurea: Polyurea prepared using only amino polyethers as soft segments.

[0117] R-value: The R-value of polyurea is a commonly used parameter in this field, which is the molar ratio of NCO groups to amino groups in the system.

[0118] Hard segment content: refers to the percentage of isocyanate compounds, chain extenders, and end-capping agents by mass in the material.

[0119] The preparation methods of polysiloxane-polyurea and polyether-polyurea described in the examples are prepolymer chain extension methods, which are methods disclosed in the art.

[0120] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0121] Example 1

[0122] The solvent used in Example 1 is a mixture of toluene and acetone (mass ratio 4:1).

[0123] This embodiment provides a method for preparing a polymer, the polymer having the structural formula shown in formula (Ⅲ), comprising the following steps:

[0124] (1) Add 10.3g of dicyclohexylmethane diisocyanate and 40g of mixed solvent to a four-necked flask equipped with a reflux condenser, a T-type three-way stopcock, a constant pressure dropping funnel, and a drying tube. Dissolve 39.4g of terminal aminopropyl polysiloxane with a molecular weight of 3300g / mol and structural formula (Ⅶ) in 160g of mixed solvent and slowly add it dropwise using a constant pressure dropping funnel. After the addition is complete, continue stirring for 20min. Mix 2.78g of compound NH2CH2CH(CH3)CH2CH2CH2NH2 (chain extender E), 0.18g of diethanolamine (chain extender G), and 0.15g of pentylamine (end-capping agent F) and dissolve them in 12g of mixed solvent. Then add the mixture dropwise to the reaction system and react at 25℃ for 20min to obtain polymer-1.

[0125] (2) Add 27.2 g of dicyclohexylmethane diisocyanate and 108 g of mixed solvent to a four-necked flask equipped with a reflux condenser, a T-type three-way stopcock, a constant pressure dropping funnel, and a drying tube. Dissolve 99.3 g of terminal amine polyether with a molecular weight of 2000 g / mol and structural formula (VIII) in 400 g of mixed solvent and slowly add it dropwise using a constant pressure dropping funnel. After the addition is complete, continue stirring the reaction for 20 min. Dissolve 5.76 g of NH2CH2CH(CH3)CH2CH2CH2NH2 and 0.19 g of pentylamine in 24 g of mixed solvent and slowly add it dropwise using a constant pressure dropping funnel. After the addition is complete, continue stirring the reaction for 20 min to obtain polymer-2.

[0126] (3) Mix polymer-1 and polymer-2 in a molar ratio of 1:2, then add 0.2wt% stannous isooctanoate, heat to 100℃ and react for 20h to obtain a polymer with the structure of formula (Ⅲ).

[0127] This embodiment also provides a method for preparing a thermoplastic elastomer. 40 parts of polysiloxane-polyurea (Ⅰ) with a hard segment content of 22 wt% (where R value is 1.02), 60 parts of polyether-polyurea (Ⅱ) with a hard segment content of 25 wt% (where R value is 1.02), and 15 parts of polymer (Ⅲ) prepared in Example 1 are mixed in 5 times their volume of a mixed solvent, which is a mixture of toluene and acetone (mass ratio 4:1). After stirring evenly, the mixture is poured into a polytetrafluoroethylene mold, cured at room temperature, and dried at 50°C for 24 hours to obtain the thermoplastic elastomer. In the polysiloxane-polyurea (Ⅰ) and polyether-polyurea (Ⅱ), X represents a dicyclohexylmethane diisocyanate segment, and Y represents (CH2)4.

[0128] Performance testing:

[0129] The thermoplastic elastomer has a tensile strength of 15 MPa, an elongation at break of 380%, a 5% thermal weight loss temperature of 315℃, a water contact angle of 108.3°, and two glass transition temperatures of -123℃ and -62℃, exhibiting good low-temperature resistance.

[0130] Example 2

[0131] The solvent used in Example 2 is a mixture of n-hexane and acetone (mass ratio 2:1).

[0132] This embodiment provides a method for preparing a polymer, the polymer having the structural formula shown in formula (Ⅳ), comprising the following steps:

[0133] (1) Add 5g of dicyclohexylmethane diisocyanate and 25g of mixed solvent to a four-necked flask equipped with a reflux condenser, a T-type three-way stopcock, a constant pressure dropping funnel, and a drying tube. Dissolve 20.2g of terminal aminopropyl polysiloxane with a molecular weight of 3300g / mol and structural formula (Ⅶ) in 100g of mixed solvent and slowly add it dropwise using a constant pressure dropping funnel. After the addition is complete, continue stirring for 15min. Mix 1.4g of compound NH2CH2CH(CH3)CH2CH2CH2NH2 (chain extender E) and 0.07g of diethanolamine (chain extender G) and dissolve them in 7g of mixed solvent. Then add the mixture dropwise to the reaction system and react at 25℃ for 15min to obtain polymer-1.

[0134] (2) Add 10.9 g of dicyclohexylmethane diisocyanate and 55 g of mixed solvent to a four-necked flask equipped with a reflux condenser, a T-type three-way stopcock, a constant pressure dropping funnel, and a drying tube. Dissolve 40.1 g of terminal amine polyether with a molecular weight of 2000 g / mol and structural formula (VIII) in 200 g of mixed solvent and slowly add it dropwise using a constant pressure dropping funnel. After the addition is complete, continue stirring the reaction for 15 min. Dissolve 2.3 g of NH2CH2CH(CH3)CH2CH2CH2NH2 and 0.15 g of butylamine (end-capping agent F) in 12 g of mixed solvent and slowly add it dropwise using a constant pressure dropping funnel. After the addition is complete, continue stirring the reaction for 15 min to obtain polymer-2.

[0135] (3) Mix polymer-1 and polymer-2 in a molar ratio of 1:4, then add 0.2wt% stannous isooctanoate, heat to 65℃ and react for 24h to obtain a polymer with the structure of formula (Ⅳ).

[0136] This embodiment also provides a method for preparing a thermoplastic elastomer. 45 parts of polysiloxane-polyurea (Ⅰ) with a hard segment content of 26 wt% (where R value is 1.00), 55 parts of polyether-polyurea (Ⅱ) with a hard segment content of 22 wt% (where R value is 1.02), and 17 parts of polymer (Ⅳ) prepared in Example 2 are mixed in 5 times their volume of a mixed solvent, which is a mixture of n-hexane and acetone (mass ratio 2:1). After stirring evenly, the mixture is poured into a polytetrafluoroethylene mold, cured at room temperature, and dried at 50°C for 24 hours to obtain the thermoplastic elastomer. In polysiloxane-polyurea (Ⅰ) and polyether-polyurea (Ⅱ), X represents a dicyclohexylmethane diisocyanate segment, and Y represents CH2CH2CH3.

[0137] Performance testing:

[0138] The thermoplastic elastomer has a tensile strength of 20.31 MPa, an elongation at break of 780%, and a thermal weight loss temperature of 315℃ for 5% thermoplastic elastomer.

[0139] Example 3

[0140] The solvent used in Example 3 is a mixture of n-hexane and tetrahydrofuran (mass ratio 3:1).

[0141] This embodiment provides a method for preparing a polymer, the polymer having the structural formula shown in formula (V), comprising the following steps:

[0142] (1) Add 3.08 g of diphenylmethane diisocyanate and 18 g of mixed solvent to a four-necked flask equipped with a reflux condenser, a T-type three-way stopcock, a constant pressure dropping funnel, and a drying tube. Dissolve 7.74 g of terminal aminopropyl polysiloxane with a molecular weight of 3300 g / mol and structural formula (Ⅶ) in 46 g of mixed solvent and slowly add it dropwise using a constant pressure dropping funnel. After the addition is complete, continue stirring for 15 min. Mix 0.82 g of compound NH2CH2CH(CH3)CH2CH2CH2NH2 (chain extender E) and 0.16 g of 2-hydroxy-1,3-propanediamine (chain extender H) and dissolve them in 6 g of mixed solvent. Then add the mixture dropwise to the reaction system and react at 25 °C for 15 min to obtain polymer-1.

[0143] (2) Add 8.91 g of diphenylmethane diisocyanate and 54 g of mixed solvent to a four-necked flask equipped with a reflux condenser, a T-type three-way stopcock, a constant pressure dropping funnel, and a drying tube. Dissolve 22.6 g of terminal amine polyether with a molecular weight of 2000 g / mol and structural formula (VIII) in 132 g of mixed solvent and slowly add it dropwise using a constant pressure dropping funnel. After the addition is complete, continue stirring the reaction for 15 min. Dissolve 2.58 g of NH2CH2CH(CH3)CH2CH2CH2NH2 and 0.06 g of hexylamine (end-capping agent F) in 15 g of mixed solvent and slowly add it dropwise using a constant pressure dropping funnel. After the addition is complete, continue stirring the reaction for 15 min to obtain polymer-2.

[0144] (3) Mix polymer-1 and polymer-2 in a molar ratio of 1:3, then add 0.2wt% stannous isooctanoate, heat to 110℃ and react for 10h to obtain a polymer with the structure of formula (V).

[0145] This embodiment also provides a method for preparing a thermoplastic elastomer. 30 parts of polysiloxane-polyurea (Ⅰ) with a hard segment content of 37 wt% (where R value is 0.99), 70 parts of polyether-polyurea (Ⅱ) with a hard segment content of 33 wt% (where R value is 1.02), and 13 parts of polymer (Ⅴ) prepared in this embodiment are mixed in 6 times their volume of a mixed solvent, which is a mixture of n-hexane and tetrahydrofuran (mass ratio 3:1). After stirring evenly, the mixture is poured into a polytetrafluoroethylene mold, cured at room temperature, and dried at 50°C for 24 hours to obtain the thermoplastic elastomer. In the polysiloxane-polyurea (Ⅰ) and polyether-polyurea (Ⅱ), X represents a diphenylmethane diisocyanate segment, and Y represents (CH2)6.

[0146] Performance testing:

[0147] The thermoplastic elastomer has a tensile strength of 24.69 MPa, an elongation at break of 486%, good hydrophobicity, a water contact angle of 110.4°, and a water absorption rate of 2.14% after immersion in water for 40 days at room temperature.

[0148] Example 4

[0149] The solvent used in Example 4 is a mixture of cyclohexane and tetrahydrofuran (mass ratio 4:1).

[0150] This embodiment provides a method for preparing a polymer, the polymer having the structural formula shown in formula (V), comprising the following steps:

[0151] (1) Add 5.6 g of dicyclohexylmethane diisocyanate and 28 g of mixed solvent to a four-necked flask equipped with a reflux condenser, a T-type three-way stopcock, a constant pressure dropping funnel, and a drying tube. Dissolve 23.6 g of terminal aminopropyl polysiloxane with a molecular weight of 3300 g / mol and structural formula (Ⅶ) in 115 g of mixed solvent and slowly add it dropwise using a constant pressure dropping funnel. After the addition is complete, continue stirring for 15 min. Mix 1.25 g of compound NH2CH2CH(CH3)CH2CH2CH2NH2 (chain extender E) and 0.31 g of 2-hydroxy-1,3-propanediamine (chain extender H) and dissolve them in 6 g of mixed solvent. Then add the mixture dropwise to the reaction system and react at 25 °C for 15 min to obtain polymer-1.

[0152] (2) Add 5.2 g of dicyclohexylmethane diisocyanate and 26 g of mixed solvent to a four-necked flask equipped with a reflux condenser, a T-type three-way stopcock, a constant pressure dropping funnel, and a drying tube. Dissolve 19.77 g of terminal amine polyether with a molecular weight of 2000 g / mol and structural formula (VIII) in 100 g of mixed solvent and slowly add it dropwise using a constant pressure dropping funnel. After the addition is complete, continue stirring the reaction for 15 min. Dissolve 1.1 g of NH2CH2CH(CH3)CH2CH2CH2NH2 and 0.04 g of pentylamine (end-capping agent F) in 6 g of mixed solvent and slowly add it dropwise using a constant pressure dropping funnel. After the addition is complete, continue stirring the reaction for 15 min to obtain polymer-2.

[0153] (3) Mix polymer-1 and polymer-2 in a molar ratio of 1:1, then add 0.2wt% stannous isooctanoate, heat to 80℃ and react for 16h to obtain a polymer with the structure of formula (V).

[0154] This embodiment also provides a method for preparing a thermoplastic elastomer. 32 parts of polysiloxane-polyurea (Ⅰ) with a hard segment content of 25 wt% (where R value is 1.01), 68 parts of polyether-polyurea (Ⅱ) with a hard segment content of 23 wt% (where R value is 0.98), and 12 parts of polymer (Ⅴ) prepared in Example 4 are mixed in 5 times their volume of a mixed solvent, which is a mixture of cyclohexane and tetrahydrofuran (mass ratio 4:1). After stirring evenly, the mixture is poured into a polytetrafluoroethylene mold, cured at room temperature, and dried at 50°C for 24 hours to obtain the thermoplastic elastomer. In polysiloxane-polyurea (Ⅰ) and polyether-polyurea (Ⅱ), X represents a dicyclohexylmethane diisocyanate segment, and Y represents (CH2)5.

[0155] Performance testing:

[0156] The thermoplastic elastomer has a tensile strength of 19.8 MPa and an elongation at break of 806%.

[0157] Example 5

[0158] The solvent used in Example 5 is a mixture of toluene and isopropanol (mass ratio 1:1).

[0159] This embodiment provides a method for preparing a polymer, the polymer having the structural formula shown in formula (VI), comprising the following steps:

[0160] (1) Add 25.3 g of dicyclohexylmethane diisocyanate and 100 g of mixed solvent to a four-necked flask equipped with a reflux condenser, a T-type three-way stopcock, a constant pressure dropping funnel, and a drying tube. Dissolve 63.8 g of terminal aminopropyl polysiloxane with a molecular weight of 2970 g / mol and structural formula (Ⅶ) in 256 g of mixed solvent and slowly add it dropwise using a constant pressure dropping funnel. After the addition is complete, continue stirring for 15 min. Mix 6.5 g of compound NH2CH2CH(CH3)CH2CH2CH2NH2 (chain extender E) and 2.46 g of 3,3'-diaminodipropylamine (chain extender I) and dissolve them in 36 g of mixed solvent. Then add the mixture dropwise to the reaction system and react at 25 °C for 15 min to obtain polymer-1.

[0161] (2) Add 64g of dicyclohexylmethane diisocyanate and 256g of mixed solvent to a four-necked flask equipped with a reflux condenser, a T-type three-way stopcock, a constant-pressure dropping funnel, and a drying tube. Dissolve 162.2g of terminal amine polyether with a molecular weight of 2000g / mol and structural formula (VIII) in 648g of mixed solvent and slowly add it dropwise using a constant-pressure dropping funnel. After the addition is complete, continue stirring the reaction for 20min. Dissolve 18.7g of NH2CH2CH(CH3)CH2CH2CH2NH2 and 0.36g of pentylamine (end-capping agent F) in 76g of mixed solvent and slowly add it dropwise using a constant-pressure dropping funnel. After the addition is complete, continue stirring the reaction for 15min to obtain polymer-2.

[0162] (3) Mix polymer-1 and polymer-2 in a molar ratio of 1:2.5, then add 0.2wt% stannous isooctanoate, heat to 50°C and react for 24h to obtain a polymer with the structure of formula (VI).

[0163] This embodiment also provides a method for preparing a thermoplastic elastomer. 40 parts of polysiloxane-polyurea (Ⅰ) with a hard segment content of 35 wt% (where R value is 0.98), 60 parts of polyether-polyurea (Ⅱ) with a hard segment content of 35 wt% (where R value is 0.98), and 20 parts of the polymer (VI) prepared in this embodiment 5 are mixed in 4 times their volume of a mixed solvent, which is a mixture of toluene and isopropanol (mass ratio 1:1). After stirring evenly, the mixture is poured into a polytetrafluoroethylene mold, cured at room temperature, and dried at 50°C for 24 hours to obtain the thermoplastic elastomer. In polysiloxane-polyurea (Ⅰ) and polyether-polyurea (Ⅱ), X represents a dicyclohexylmethane diisocyanate segment, and Y represents CH2CH2CH3.

[0164] Performance testing:

[0165] The thermoplastic elastomer has a tensile strength of 31.65 MPa, an elongation at break of 471%, and a water absorption rate of 1.27% after immersion in water for 40 days at room temperature.

[0166] Example 6

[0167] The solvent used in Example 6 is a mixture of cyclohexane and isopropanol (mass ratio 2:1).

[0168] This embodiment provides a method for preparing a polymer, the polymer having the structural formula shown in formula (Ⅳ), comprising the following steps:

[0169] (1) Add 4.55g of diphenylmethane diisocyanate and 33g of mixed solvent to a four-necked flask equipped with a reflux condenser, a T-type three-way stopcock, a constant pressure dropping funnel, and a drying tube. Dissolve 30g of terminal aminopropyl polysiloxane with a molecular weight of 3300g / mol and structural formula (Ⅶ) in 210g of mixed solvent and slowly add it dropwise using a constant pressure dropping funnel. After the addition is complete, continue stirring for 15min. Mix 0.885g of compound NH2CH2CH(CH3)CH2CH2CH2NH2 (chain extender E) and 0.2g of 2-hydroxy-1,3-propanediamine (chain extender G) and dissolve them in 7g of mixed solvent. Then add the mixture dropwise to the reaction system and react at 25℃ for 15min to obtain polymer-1.

[0170] (2) Add 5.4 g of diphenylmethane diisocyanate and 38 g of mixed solvent to a four-necked flask equipped with a reflux condenser, a T-type three-way stopcock, a constant pressure dropping funnel, and a drying tube. Dissolve 30 g of terminal amine polyether with a molecular weight of 2000 g / mol and structural formula (VIII) in 210 g of mixed solvent and slowly add it dropwise using a constant pressure dropping funnel. After the addition is complete, continue stirring the reaction for 20 min. Dissolve 0.7 g of NH2CH2CH(CH3)CH2CH2CH2NH2 and 0.05 g of pentylamine (end-capping agent F) in 5 g of mixed solvent and slowly add it dropwise using a constant pressure dropping funnel. After the addition is complete, continue stirring the reaction for 15 min to obtain polymer-2.

[0171] (3) Mix polymer-1 and polymer-2 in a molar ratio of 1:2, then add 0.2wt% stannous isooctanoate, heat to 65℃ and react for 24h to obtain a polymer with the structure of formula (Ⅳ).

[0172] This embodiment also provides a method for preparing a thermoplastic elastomer. 50 parts of polysiloxane-polyurea (Ⅰ) with a hard segment content of 16 wt% (where R value is 0.99), 50 parts of polyether-polyurea (Ⅱ) with a hard segment content of 16 wt% (where R value is 1.02), and 8 parts of polymer (Ⅳ) prepared in this embodiment 6 are mixed in 7 times their volume of a mixed solvent, which is a mixture of cyclohexane and isopropanol (mass ratio 2:1). After stirring evenly, the mixture is poured into a polytetrafluoroethylene mold, cured at room temperature, and dried at 50°C for 24 hours to obtain the thermoplastic elastomer. In polysiloxane-polyurea (Ⅰ) and polyether-polyurea (Ⅱ), X is diphenylmethane diisocyanate, and Y is (CH2)4.

[0173] Performance testing:

[0174] The thermoplastic elastomer has a tensile strength of 16.5 MPa and an elongation at break of 820%.

[0175] Example 7

[0176] The solvent used in Example 7 is a mixture of toluene and acetone (mass ratio 3:1).

[0177] This embodiment provides a method for preparing a polymer, the polymer having the structural formula shown in formula (VI), comprising the following steps:

[0178] (1) Add 13.6 g of hexamethylene diisocyanate and 68 g of mixed solvent to a four-necked flask equipped with a reflux condenser, a T-type three-way stopcock, a constant pressure dropping funnel, and a drying tube. Dissolve 30.3 g of terminal aminopropyl polysiloxane with a molecular weight of 3000 g / mol and structural formula (Ⅶ) in 150 g of mixed solvent and slowly add it dropwise using a constant pressure dropping funnel. After the addition is complete, continue stirring for 20 min. Mix 4.68 g of compound NH2CH2CH(CH3)CH2CH2CH2NH2 (chain extender E) and 2.3 g of 3,3'-diaminodipropylamine (chain extender I) and dissolve them in 35 g of mixed solvent. Then add the mixture dropwise to the reaction system and react at 25 °C for 20 min to obtain polymer-1.

[0179] (2) Add 31.1 g of hexamethylene diisocyanate and 156 g of mixed solvent to a four-necked flask equipped with a reflux condenser, a T-type three-way stopcock, a constant pressure dropping funnel, and a drying tube. Dissolve 52.4 g of terminal amine polyether with a molecular weight of 2000 g / mol and structural formula (VIII) in 262 g of mixed solvent and slowly add it dropwise using a constant pressure dropping funnel. After the addition is complete, continue stirring the reaction for 20 min. Dissolve 18.3 g of NH2CH2CH(CH3)CH2CH2CH2NH2 and 0.11 g of pentylamine (end-capping agent F) in 92 g of mixed solvent and slowly add it dropwise using a constant pressure dropping funnel. After the addition is complete, continue stirring the reaction for 20 min to obtain polymer-2.

[0180] (3) Mix polymer-1 and polymer-2 in a molar ratio of 1:3.5, then add 0.2wt% stannous isooctanoate, heat to 70℃ and react for 18h to obtain a polymer with the structure of formula (VI).

[0181] This embodiment also provides a method for preparing a thermoplastic elastomer. 43 parts of polysiloxane-polyurea (Ⅰ) with a hard segment content of 40 wt% (where R value is 0.98), 57 parts of polyether-polyurea (Ⅱ) with a hard segment content of 48 wt% (where R value is 1.01), and 10 parts of the polymer (VI) prepared in this embodiment 7 are mixed in 5 times their volume of a mixed solvent, which is a mixture of toluene and acetone (mass ratio 3:1). After stirring evenly, the mixture is poured into a polytetrafluoroethylene mold, cured at room temperature, and dried at 50°C for 24 hours to obtain the thermoplastic elastomer. In the polysiloxane-polyurea (Ⅰ) and polyether-polyurea (Ⅱ), X represents hexamethylene diisocyanate segments, and Y represents CH2CH2CH2.

[0182] Performance testing:

[0183] The thermoplastic elastomer has a tensile strength of 50.4 MPa and an elongation at break of 121%.

[0184] Comparative Example 1

[0185] The performance of the polysiloxane-polyurea thermoplastic elastomer (Ⅰ) with a hard segment content of 22 wt% used in Example 1 was tested. The test results were: tensile strength of 13.23 MPa and elongation at break of 597%.

[0186] Comparative Example 2

[0187] The performance was tested using polyether-polyurea (II) with a hard segment content of 25 wt% as used in Example 1. The test results were as follows: tensile strength of 24.12 MPa, elongation at break of 346%, and water absorption rate of more than 3.5% after immersion in water for 40 days at room temperature.

[0188] Comparative Example 3

[0189] Preparation of polysiloxane-polyether-polyurea:

[0190] Prepare a mixed solvent of toluene and acetone at a mass ratio of 2:1. Add 2.6235 g of 4,4'-dicyclohexylmethane diisocyanate and 12.5 g of the mixed solvent to a flask equipped with a reflux condenser, a three-way stopcock, a constant-pressure dropping funnel, and a drying tube. Dissolve 2 g of a 2000 g / mol polyether and 2 g of a 3000 g / mol polysiloxane in 20 g of the mixed solvent and add them dropwise, stirring for 20 min. Then, dissolve 0.7747 g of 2-methyl-1,5-diaminopentane in the mixed solvent and add it dropwise to the prepolymer, stirring for 20 min.

[0191] The solvent was removed from the solution obtained from the above reaction, and the solution was poured into a polytetrafluoroethylene mold, cured at room temperature, and dried at 50°C for 24 hours in a vacuum drying oven to obtain a polysiloxane-polyether-polyurea thermoplastic elastomer.

[0192] Performance testing: The tensile strength of the polysiloxane-polyether-polyurea is 15.28 MPa, and the elongation at break is 463%.

[0193] Comparative Example 4

[0194] Preparation of polysiloxane-polyurea / polyether-polyurea blends:

[0195] A mixed solvent of toluene and acetone was prepared at a mass ratio of 4:1. 40 parts of polysiloxane-polyurea (Ⅰ) with a hard segment content of 16 wt% (where R value is 0.99) and 60 parts of polyether-polyurea (Ⅱ) with a hard segment content of 16 wt% (where R value is 1.02), used in Example 6, were stirred evenly in the mixed solvent. The resulting blend solution was then removed from the solvent, poured into a polytetrafluoroethylene mold, cured at room temperature, and dried in a vacuum drying oven at 50°C for 24 hours to obtain a polysiloxane-polyurea / polyether-polyurea thermoplastic elastomer.

[0196] Performance testing: The tensile strength of the polysiloxane-polyurea / polyether-polyurea blend is 5.87 MPa, and the elongation at break is 137%.

[0197] Comparative Example 5

[0198] Preparation of polysiloxane-polyurea / polyether-polyurea blends:

[0199] A mixed solvent of cyclohexane and isopropanol was prepared at a mass ratio of 2:1. 50 parts of polysiloxane-polyurea (Ⅰ) with a hard segment content of 16 wt% (where R value is 0.99), 50 parts of polyether-polyurea (Ⅱ) with a hard segment content of 16 wt% (where R value is 1.02), and 8 parts of polysiloxane-polyether-polyurea prepared in Comparative Example 3 were mixed in the mixed solvent and stirred until homogeneous. The resulting blend solution was then freed from the solvent, poured into a polytetrafluoroethylene mold, cured at room temperature, and dried in a vacuum drying oven at 50°C for 24 hours to obtain a polysiloxane-polyurea / polyether-polyurea thermoplastic elastomer.

[0200] Performance testing: The tensile strength of the polysiloxane-polyurea / polyether-polyurea thermoplastic elastomer is 6.12 MPa, and the elongation at break is 153%.

[0201] By comparing Comparative Examples 1 and 2 with Example 5, it can be found that the blending method can compensate for the strength defects of polysiloxane-polyurea while retaining the water resistance properties of organosilicon. Comparative Example 4 directly blended the two polyureas in a solvent without adding any compatibilizer, resulting in a polysiloxane-polyurea / polyether-polyurea thermoplastic elastomer with relatively poor performance. In Comparative Example 5, when the polysiloxane-polyether-polyurea obtained in Comparative Example 3 was used as a polyurea compatibilizer, the resulting polysiloxane-polyurea / polyether-polyurea also exhibited poor performance, indicating that polymers with other structures have relatively poor compatibilizing effects when used as compatibilizers.

[0202] As can be seen from the above embodiments, the present invention first prepares polymers with polysiloxane-polyurea and polyether-polyurea structures, uses them as compatibilizers, and then mixes them with polysiloxane-polyurea and polyether-polyurea to obtain thermoplastic elastomers. The resulting elastomers simultaneously possess the weather resistance, hydrophobicity, temperature resistance and flexibility of polysiloxanes, as well as the high strength and high modulus of polyurea, resulting in excellent comprehensive performance.

[0203] 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 polymer, characterized in that, The polymer is selected from one of the general formulas shown in formulas (III), (IV), (V), and (VI): Where q is independently selected from integers greater than 1 and less than or equal to 4; p and s are independently selected from integers from 2 to 4; o is independently selected from integers from 50 to 100; In the general formula, I represents polysiloxane-polyurea, and the structure of formula I is as follows: ； In the general formula, II stands for polyether-polyurea, and the structure of formula II is as follows: ； Wherein, n and r are independently selected from integers from 15 to 65; m and m′ are independently selected from integers from 50 to 100; X is independently selected from one of the dicyclohexylmethane diisocyanate segment, diphenylmethane diisocyanate segment, hexamethylene diisocyanate segment, and toluene diisocyanate segment; and Y is independently selected from one of (CH2)4, (CH2)5, (CH2)6, and CH2CH2CH2.

2. A method for preparing the polymer according to claim 1, characterized in that, Includes the following steps: (1) The diisocyanate compound and the terminal aminopropyl polysiloxane were mixed in a solvent and reacted. Compound N was added to the reaction product and the reaction was continued to obtain polymer-1. (2) The diisocyanate compound and the terminal amine polyether were mixed in a solvent and reacted. Compound N was added to the reaction product and the reaction was continued to obtain polymer-2. The compound N is independently selected from one or more of chain extender E, end capping agent F, chain extender G, chain extender H and chain extender I; (3) Polymer-1, polymer-2 and catalyst are mixed and reacted to obtain polymer; The chain extender E is selected from one or more of NH2(CH2)4NH2, NH2(CH2)5NH2, NH2(CH2)6NH2 and NH2CH2CH(CH3)CH2CH2CH2NH2; The end-capping agent F is selected from one or more of CH3(CH2)2NH2, CH3(CH2)3NH2, CH3(CH2)4NH2 and CH3(CH2)5NH2; The chain extender G has the general formula shown in formula (IX): Where p is an independent integer taken from 2 to 4; The chain extender H has the general formula shown in formula (X): Where q is independently taken from integers greater than 1 and less than or equal to 4; The chain extender I has the general formula shown in formula (XI): Where s is an independent integer taken from 2 to 4.

3. The method for preparing the polymer according to claim 2, characterized in that, In step (1) and / or step (2), the solvent independently comprises one or more of N,N-dimethylformamide, acetone, tetrahydrofuran, isopropanol, n-hexane, toluene, and cyclohexane.

4. The method for preparing the polymer according to claim 2, characterized in that, In step (1) and / or step (2), the diisocyanate compound independently includes one or more of dicyclohexylmethane diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate and toluene diisocyanate.

5. The method for preparing the polymer according to claim 2, characterized in that, The terminal aminopropyl polysiloxane has the general formula shown in formula (VII): Where n is selected from integers between 15 and 65; The terminal amine polyether has the general formula shown in formula (VIII): Where r is selected from integers from 15 to 65.

6. The method for preparing the polymer according to claim 2, characterized in that, The catalyst is stannous isooctanoate or dibutyltin dilaurate.

7. A compatibilizer, characterized in that, Includes the polymer of claim 1.

8. A thermoplastic elastomer, characterized in that, The thermoplastic elastomer is composed of 20 to 70 parts of polysiloxane-polyurea of ​​Formula I, 30 to 80 parts of polyether-polyurea of ​​Formula II, and 3 to 20 parts of the polymer of claim 1, wherein the content of hard segments in the polysiloxane-polyurea and the polyether-polyurea is independently 15 to 50 wt%, and the R value is independently 0.98 to 1.

02.

9. A method for preparing the thermoplastic elastomer according to claim 8, characterized in that, A thermoplastic elastomer can be obtained by mixing 20-70 parts of the polysiloxane-polyurea of ​​Formula I, 30-80 parts of the polyether-polyurea of ​​Formula II, and 3-20 parts of the polymer of claim 1 in a solvent and then drying the mixture.

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