High-strength repairable polyurethane elastomer and preparation method thereof

Abstract

The invention relates to the technical field of polyurethane elastomers, in particular to a high-strength repairable polyurethane elastomer and a preparation method thereof. The problem that mechanical strength and repairable performance are difficult to consider at the same time in the common technology is solved. Comprising a solvent, polytetramethylene ether glycol, diphenylmethane diisocyanate, dibutyltin dilaurate and cystamine dihydrochloride. The invention further discloses a preparation method of the high-strength repairable polyurethane elastomer. According to the polyurethane elastomer prepared by the invention, the self-repairing capability of the material is remarkably improved while the high strength is maintained. The preparation process disclosed by the invention is simple and easy to implement, has a good industrial application prospect, can be used for producing elastomer products with higher performance and low maintenance, and reduces environmental pollution and material waste.

Description

Technical Field

[0001] The invention relates to the technical field of polyurethane elastomers, and in particular to a high-strength, repairable polyurethane elastomer and a preparation method thereof. Background Art

[0002] Polyurethane elastomers are widely used in the fields of industry, medicine, electronics, etc. due to their excellent mechanical properties, chemical resistance and good processing properties. In the industrial field, polyurethane elastomers are often used to make seals, transmission belts and shock absorbers; in the medical field, they are used to make flexible implants, medical catheters and wound dressings; in the electronics field, polyurethane elastomers are used to make protective shells for electronic devices due to their excellent electrical insulation properties.

[0003] Traditional polyurethane elastomers usually adopt an irreversible cross-linked network structure. Although this structure enhances the mechanical properties of the material, it also limits the dynamic reconstruction ability of the material, resulting in poor repair performance.

[0004] Therefore, there is an urgent need to propose a high-strength, repairable polyurethane elastomer and a preparation method to solve the above technical problems. Summary of the invention

[0005] The present invention is to solve the problem that it is difficult to balance mechanical strength and repairability formed by conventional technologies. A brief overview of the present invention is given below to provide a basic understanding of certain aspects of the present invention. It should be understood that this overview is not an exhaustive overview of the present invention. It is not intended to identify the key or important parts of the present invention, nor is it intended to limit the scope of the present invention.

[0006] The technical solution of the present invention:

[0007] A high-strength and repairable polyurethane elastomer consists of a solvent, polytetramethylene ether glycol, diphenylmethane diisocyanate, dibutyltin dilaurate and cystamine dihydrochloride.

[0008] The mass fraction of the solvent is 200 parts, the mass fraction of polytetramethylene ether glycol is 40 parts, the mass fraction of diphenylmethane diisocyanate is 10 parts, the mass fraction of dibutyltin dilaurate is 1.5 parts, and the mass fraction of cystamine dihydrochloride is 0.2-0.5 parts.

[0009] Preferably, the solvent is one or more of ethyl acetate, N,N-dimethylacetamide, N,N-dimethylformamide, and dimethyl sulfoxide.

[0010] Preferably, the molecular weight of the polytetramethylene ether glycol is 2000.

[0011] A method for preparing a high-strength, repairable polyurethane elastomer comprises the following steps:

[0012] Step 1: Place the solvent in a reaction vessel, heat and stir, and introduce nitrogen protection;

[0013] Step 2: Add polytetramethylene ether glycol into a reaction container, and then drop diphenylmethane diisocyanate into the reaction container through a constant pressure dropping funnel;

[0014] Step 3: After the dropwise addition is completed, dibutyltin dilaurate is added dropwise to react and generate a prepolymer.

[0015] Step 4: After the prepolymer solution is cooled to room temperature, cystamine dihydrochloride is added dropwise, and the mixture is reheated and reacted again;

[0016] Step 5: After the reaction is completed, the mixture is transferred to a vacuum device and the solvent is removed by evaporation to obtain a PUU elastomer;

[0017] Step 6: Place the PUU elastomer in a vacuum environment at 80°C for post-treatment to ensure the performance stability and purity of the material.

[0018] Preferably: in step 1, the stirring speed is 100 r / min and the temperature is raised to 80°C.

[0019] Preferably, the dropping time in step 2 is 30 min.

[0020] Preferably, in step 3, the reaction is carried out at a temperature of 80° C. for 1.5 hours.

[0021] Preferably, in step 4, the mixture is heated to 40° C. and the reaction time is 2 hours.

[0022] Preferably, the post-treatment time in step 6 is 8 hours.

[0023] The present invention has the following beneficial effects:

[0024] The polyurethane elastomer prepared by the present invention significantly improves the self-repairing ability of the material while maintaining high strength;

[0025] The present invention realizes precise control of the microstructure of the elastomer and significantly improves the elastic modulus and durability of the material;

[0026] The preparation process of the invention is simple and easy, has good industrial application prospects, can be used to produce higher performance, low maintenance elastomer products, and reduces environmental pollution and material waste. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is described below by specific embodiments. However, it should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0028] Specific implementation method 1: A high-strength, repairable polyurethane elastomer in this implementation method is composed of a solvent, polytetramethylene ether glycol, diphenylmethane diisocyanate, dibutyltin dilaurate, and cystamine dihydrochloride.

[0029] The mass fraction of the solvent is 200 parts, the mass fraction of polytetramethylene ether glycol is 40 parts, the mass fraction of diphenylmethane diisocyanate is 10 parts, the mass fraction of dibutyltin dilaurate is 1.5 parts, and the mass fraction of cystamine dihydrochloride is 0.2-0.5 parts.

[0030] The ratio and proportion of the solvent to polytetramethylene ether glycol and MDI provide suitable viscosity and reactivity, ensuring that the polyurethane elastomer has both high strength and good elasticity. The appropriate amount of catalyst DBTDL ensures the efficient reaction. The addition of cystamine dihydrochloride makes the final polyurethane elastomer repairable and able to restore certain functions after being damaged.

[0031] This polyurethane elastomer is suitable for applications that require high strength and repairability, such as high-performance seals, wear-resistant materials, and electronic equipment protection materials.

[0032] Specific implementation method 2: In this implementation method, a high-strength, repairable polyurethane elastomer is provided, wherein the solvent is one or more of ethyl acetate, N,N-dimethylacetamide, N,N-dimethylformamide, and dimethyl sulfoxide.

[0033] Mixing the above solvents can combine their respective advantages. For example, a mixture of ethyl acetate and DMAA or DMF can take into account low boiling point, rapid volatility and high solubility, helping to dissolve various reactants in the polyurethane synthesis process.

[0034] The mixed solvent can also adjust the fluidity and viscosity of the reaction at different stages to better control the progress of the polymerization reaction and ultimately obtain a polyurethane elastomer with high strength and repairable properties.

[0035] Specific implementation method three: In this implementation method, a high-strength, repairable polyurethane elastomer, the molecular weight of polytetramethylene ether glycol is 2000.

[0036] Using polytetramethylene ether glycol with a molecular weight of 2000 as the soft segment can not only greatly improve the strength, toughness and wear resistance of the polyurethane elastomer, but also effectively improve its repairability, enabling it to restore its original mechanical properties after damage.

[0037] Specific embodiment 4: A method for preparing a high-strength, repairable polyurethane elastomer in this embodiment comprises the following steps:

[0038] Step 1: Place the solvent in a reaction vessel, heat and stir, and introduce nitrogen protection;

[0039] Step 2: Add polytetramethylene ether glycol into a reaction container, and then drop diphenylmethane diisocyanate into the reaction container through a constant pressure dropping funnel;

[0040] Step 3: After the dropwise addition is completed, dibutyltin dilaurate is added dropwise to react and generate a prepolymer.

[0041] Step 4: After the prepolymer solution is cooled to room temperature, cystamine dihydrochloride is added dropwise, and the mixture is reheated and reacted again;

[0042] Step 5: After the reaction is completed, the mixture is transferred to a vacuum device and the solvent is removed by evaporation to obtain a PUU elastomer;

[0043] Step 6: Place the PUU elastomer in a vacuum environment at 80°C for post-treatment to ensure the performance stability and purity of the material.

[0044] This preparation method successfully synthesized a polyurethane elastomer with high strength and repairability through a series of steps, combining nitrogen protection, solvent dissolution, precise addition of isocyanate, catalyst-promoted reaction, cystamine salt cross-linking reaction, and vacuum evaporation to remove solvent. This material is not only suitable for high-strength and wear-resistant applications, but can also be repaired after material damage through cross-linking reaction, extending its service life.

[0045] Specific implementation method 5: In this implementation method, a method for preparing a high-strength, repairable polyurethane elastomer is used. In step 1, the stirring speed is 100r / min, and the temperature is raised to 80°C to ensure that the solvent can effectively dissolve the reactants added subsequently and is ready for polymerization reaction.

[0046] Specific embodiment six: This embodiment is a method for preparing a high-strength, repairable polyurethane elastomer. The dripping time in step two is 30 minutes, which can control the reaction rate, prevent local overheating and over-reaction, promote uniform mixing of reactants, improve the consistency of the final product, optimize the prepolymer structure, ensure that the polyurethane elastomer has high strength and ideal elasticity, reduce the occurrence of side reactions, improve the purity and performance of the material, ensure appropriate cross-linking density, and improve the repairability and toughness of the material.

[0047] Specific implementation method seven: This implementation method is a method for preparing a high-strength, repairable polyurethane elastomer, wherein the reaction in step three is carried out at a temperature of 80° C. for 1.5 hours.

[0048] At a reaction temperature of 80°C, the reaction rate is moderate, which is conducive to the formation of a relatively moderate molecular weight and cross-linked structure, and can ensure sufficient reaction while avoiding the formation of excessive cross-linking degree. Appropriate cross-linking density not only improves the strength of the polyurethane elastomer, but also maintains the elasticity and flexibility of the material.

[0049] Specific implementation method eight: In this implementation method, a method for preparing a high-strength, repairable polyurethane elastomer is provided, wherein the temperature is heated to 40° C. in step four, and the reaction time is 2 hours.

[0050] Reacting at 40°C for 2 hours can promote the microstructural adjustment inside the polyurethane elastomer, allowing the material to self-repair when damaged by external forces. In this temperature range, the polyurethane segments still have a certain fluidity, so the damaged areas can be reconnected through external conditions to restore their original shape and performance, thereby enhancing the repairability of the material and effectively reducing the occurrence of side reactions, thereby ensuring the purity and performance of the material.

[0051] Specific implementation method 9: In the method for preparing a high-strength, repairable polyurethane elastomer according to this implementation method, the post-processing time in step 6 is 8 hours.

[0052] During the post-treatment process, the microstructure of the polyurethane elastomer surface will also change. Prolonging the treatment time helps to improve the surface quality of the material, reduce surface defects, bubbles or unevenness, and ensure that the appearance and performance of the product meet high standards. For high-strength, repairable elastomers, optimizing the surface quality can also improve its service life and performance in practical applications.

[0053] Example 1

[0054] A method for preparing a high-strength, repairable polyurethane elastomer comprises the following steps:

[0055] Step 1: Place 200 mL of ethyl acetate into a reaction vessel, stir at 100 r / min, heat to 80°C, and introduce nitrogen protection;

[0056] Step 2: Add 40g of polytetramethylene ether glycol PTMEG into a reaction container, put 10g of diphenylmethane diisocyanate MDI into a constant pressure dropping funnel, and add it dropwise into the reaction container for 30min;

[0057] Step 3: dropwise add 1.5 mL of catalyst dibutyltin dilaurate DBTDL, react at 80° C. for 1.5 hours to generate a prepolymer;

[0058] Step 4: After the prepolymer is cooled to room temperature, 0.13 g of 1,4-dibutylamine is added dropwise, the mixture is reheated to 40°C, and the reaction is continued for 2 hours;

[0059] Step 5: After the reaction is completed, the solution is transferred to a vacuum device to remove the solvent by evaporation to obtain a PUU elastomer;

[0060] Step 6: Post-treat the PUU elastomer in a vacuum environment at 80°C for 8 hours to ensure the performance stability and purity of the material.

[0061] Example 2

[0062] A method for preparing a high-strength, repairable polyurethane elastomer comprises the following steps:

[0063] Step 1: Place 200 mL of ethyl acetate in a reaction vessel, stir at 100 r / min, heat to 80°C, and introduce nitrogen protection;

[0064] Step 2: Add 40 g of polytetramethylene ether glycol PTMEG into a reaction container, put 10 g of diphenylmethane diisocyanate MDI into a constant pressure dropping funnel, and add dropwise to the reaction container for 30 min;

[0065] Step 3: dropwise add 1.5 mL of catalyst dibutyltin dilaurate DBTDL, react at 80° C. for 1.5 hours to generate a prepolymer;

[0066] Step 4: After the prepolymer solution is cooled to room temperature, 0.16 g of diaminopyridine is added dropwise, the mixture is reheated to 40°C, and the reaction is continued for 2 hours;

[0067] Step 5: After the reaction is completed, the solution is transferred to a vacuum device to remove the solvent by evaporation to obtain a PUU elastomer;

[0068] Step 6: Post-treat the PUU elastomer in a vacuum environment at 80°C for 8 hours to ensure the performance stability and purity of the material.

[0069] Example 3

[0070] A method for preparing a high-strength, repairable polyurethane elastomer comprises the following steps:

[0071] Step 1: Place 200 mL of N,N-dimethylformamide (DMF) into a reaction vessel, stir at a speed of 100 r / min, heat to 80°C, and introduce nitrogen protection;

[0072] Step 2: Weigh 40 g of polytetramethylene ether glycol PTMEG and add it into a reaction container, put 10 g of diphenylmethane diisocyanate MDI into a constant pressure dropping funnel, and add it dropwise into the reaction container for 30 min;

[0073] Step 3: dropwise add 1.5 mL of catalyst dibutyltin dilaurate DBTDL, react at 80° C. for 1.5 hours to generate a prepolymer;

[0074] Step 4: After the prepolymer solution is cooled to room temperature, 0.23 g of cystamine is added dropwise, the mixture is reheated to 40° C., and the reaction is continued for 2 hours;

[0075] Step 5: After the reaction is completed, the solution is transferred to a vacuum device to remove the solvent by evaporation to obtain a PUU elastomer;

[0076] Step 6: Post-treat the PUU elastomer in a vacuum environment at 80°C for 8 hours to ensure the performance stability and purity of the material.

[0077] Example 4

[0078] A method for preparing a high-strength, repairable polyurethane elastomer comprises the following steps:

[0079] Step 1: Place 200 mL of dimethyl sulfoxide (DMSO) into a reaction vessel, stir at 100 r / min, heat to 80°C, and introduce nitrogen protection;

[0080] Step 2: Add 40 g of polytetramethylene ether glycol PTMEG into a reaction container, put 10 g of diphenylmethane diisocyanate MDI into a constant pressure dropping funnel, and add dropwise to the reaction container for 30 min;

[0081] Step 3: dropwise add 1.5 mL of catalyst dibutyltin dilaurate DBTDL, react at 80° C. for 1.5 hours to generate a prepolymer;

[0082] Step 4: After the prepolymer solution is cooled to room temperature, 0.23 g of cystamine is added dropwise, the mixture is reheated to 40° C., and the reaction is continued for 2 hours;

[0083] Step 5: After the reaction is completed, the solution is transferred to a vacuum device to remove the solvent by evaporation to obtain a PUU elastomer;

[0084] Step 6: Post-treat the PUU elastomer in a vacuum environment at 80°C for 8 hours to ensure the performance stability and purity of the material.

[0085] Example 5

[0086] A method for preparing a high-strength, repairable polyurethane elastomer comprises the following steps:

[0087] Step 1: Place 200 mL of ethyl acetate into a reaction vessel, stir at 100 r / min, heat to 80°C, and introduce nitrogen protection;

[0088] Step 2: Add 40 g of polytetramethylene ether glycol PTMEG into a reaction container, put 10 g of diphenylmethane diisocyanate MDI into a constant pressure dropping funnel, and add dropwise to the reaction container for 30 min;

[0089] Step 3: dropwise add 1.5 mL of catalyst dibutyltin dilaurate DBTDL, react at 80° C. for 1.5 hours to generate a prepolymer;

[0090] Step 4: After the prepolymer solution is cooled to room temperature, 0.23 g of cystamine is added dropwise, the mixture is reheated to 40° C., and the reaction is continued for 2 hours;

[0091] Step 5: After the reaction is completed, the solution is transferred to a vacuum device to remove the solvent by evaporation to obtain a PUU elastomer;

[0092] Step 6: Post-treat the PUU elastomer in a vacuum environment at 80°C for 8 hours to ensure the performance stability and purity of the material.

[0093] Example 5

[0094] A method for preparing a high-strength, repairable polyurethane elastomer comprises the following steps:

[0095] Step 1: Place 200 mL of ethyl acetate into a reaction vessel, stir at 100 r / min, heat to 80°C, and introduce nitrogen protection;

[0096] Step 2: Add 40 g of polytetramethylene ether glycol PTMEG into a reaction container, put 10 g of diphenylmethane diisocyanate MDI into a constant pressure dropping funnel, and add dropwise to the reaction container for 30 min;

[0097] Step 3: dropwise add 1.5 mL of catalyst dibutyltin dilaurate DBTDL, react at 80° C. for 1.5 hours to generate a prepolymer;

[0098] Step 4: After the prepolymer solution is cooled to room temperature, 0.35 g of cystamine is added dropwise, the mixture is reheated to 40° C., and the reaction is continued for 2 hours;

[0099] Step 5: After the reaction is completed, the solution is transferred to a vacuum device to remove the solvent by evaporation to obtain a PUU elastomer;

[0100] Step 6: Post-treat the PUU elastomer in a vacuum environment at 80°C for 8 hours to ensure the performance stability and purity of the material.

[0101] Example 6

[0102] A method for preparing a high-strength, repairable polyurethane elastomer comprises the following steps:

[0103] Step 1: Place 200 mL of ethyl acetate in a reaction vessel, stir at 100 r / min, heat to 80°C, and introduce nitrogen protection;

[0104] Step 2: Add 40 g of polytetramethylene ether glycol PTMEG into a reaction container, put 10 g of diphenylmethane diisocyanate MDI into a constant pressure dropping funnel, and add dropwise to the reaction container for 30 min;

[0105] Step 3: dropwise add 1.5 mL of catalyst dibutyltin dilaurate DBTDL, react at 80° C. for 1.5 hours to generate a prepolymer;

[0106] Step 4: After the prepolymer solution is cooled to room temperature, 0.46 g of cystamine is added dropwise, the mixture is reheated to 40° C., and the reaction is continued for 2 hours;

[0107] Step 5: After the reaction is completed, the solution is transferred to a vacuum device to remove the solvent by evaporation to obtain a PUU elastomer;

[0108] Step 6: Post-treat the PUU elastomer in a vacuum environment at 80°C for 8 hours to ensure the performance stability and purity of the material.

[0109] Comparative Example 1

[0110] A method for preparing a high-strength, repairable polyurethane elastomer comprises the following steps:

[0111] Step 1: Place 200 mL of ethyl acetate in a reaction vessel, stir at 100 r / min, heat to 80°C, and introduce nitrogen protection;

[0112] Step 2: Add 40 g of polytetramethylene ether glycol PTMEG into a reaction container, put 10 g of diphenylmethane diisocyanate MDI into a constant pressure dropping funnel, and add dropwise to the reaction container for 30 min;

[0113] Step 3: dropwise add 1.5 mL of catalyst dibutyltin dilaurate DBTDL, react at 80° C. for 1.5 hours to generate a prepolymer;

[0114] Step 4: After the prepolymer solution is cooled to room temperature, 0.13 g of 1,4-dibutylamine is added dropwise, the mixture is reheated to 40° C., and the reaction is continued for 2 hours;

[0115] Step 5: After the reaction is completed, the solution is transferred to a vacuum device to remove the solvent by evaporation to obtain a PUU elastomer;

[0116] Step 6: Post-treat the PUU elastomer in a vacuum environment at 80°C for 8 hours to ensure the performance stability and purity of the material.

[0117] Comparative Example 2

[0118] A method for preparing a high-strength, repairable polyurethane elastomer comprises the following steps:

[0119] Step 1: Place 200 mL of ethyl acetate into a reaction vessel, stir at 100 r / min, heat to 80°C, and introduce nitrogen protection;

[0120] Step 2: Add 40 g of polytetramethylene ether glycol PTMEG into a reaction container, put 10 g of diphenylmethane diisocyanate MDI into a constant pressure dropping funnel, and add dropwise to the reaction container for 30 min;

[0121] Step 3: dropwise add 1.5 mL of catalyst dibutyltin dilaurate DBTDL, react at 80° C. for 1.5 hours to generate a prepolymer;

[0122] Step 4: After the prepolymer solution is cooled to room temperature, 0.16 g of diaminopyridine is added dropwise, the mixture is reheated to 40°C, and the reaction is continued for 2 hours;

[0123] Step 5: After the reaction is completed, the solution is transferred to a vacuum device to remove the solvent by evaporation to obtain a PUU elastomer;

[0124] Step 6: Post-treat the PUU elastomer in a vacuum environment at 80°C for 8 hours to ensure the performance stability and purity of the material.

[0125] Comparative Example 3

[0126] A method for preparing a high-strength, repairable polyurethane elastomer comprises the following steps:

[0127] Step 1: Place 200 mL of ethyl acetate in a reaction vessel, stir at 100 r / min, heat to 80°C, and introduce nitrogen protection;

[0128] Step 2: Add 40 g of polytetramethylene ether glycol PTMEG into a reaction container, put 10 g of diphenylmethane diisocyanate MDI into a constant pressure dropping funnel, and add dropwise to the reaction container for 30 min;

[0129] Step 3: dropwise add 1.5 mL of catalyst dibutyltin dilaurate DBTDL, react at 80° C. for 1.5 hours to generate a prepolymer;

[0130] Step 4: After the prepolymer solution is cooled to room temperature, 0.23 g of 2,2-aminodiphenyl disulfide is added dropwise, the mixture is reheated to 40° C., and the reaction is continued for 2 hours;

[0131] Step 5: After the reaction is completed, the solution is transferred to a vacuum device to remove the solvent by evaporation to obtain a PUU elastomer;

[0132] Step 6: Post-treat the PUU elastomer in a vacuum environment at 80°C for 8 hours to ensure the performance stability and purity of the material.

[0133] The high-strength, repairable polyurethane elastomer of the present invention has broad application prospects, especially in fields that require both mechanical properties and repair capabilities. First, in terms of self-healing coatings, the elastomer can effectively deal with performance degradation problems caused by mechanical damage or environmental factors. Traditional coating materials are often difficult to self-repair, and the materials of the present invention can significantly extend the life of the coating and reduce maintenance and replacement costs. At present, self-healing elastomeric materials on the market still face problems such as insufficient durability, slow repair rate and poor environmental adaptability. The present invention solves these problems by optimizing the dynamic characteristics of chemical bonds and the structure of polymer chains. Future directions for improvement include further improving repair efficiency, enhancing chemical corrosion resistance, and exploring multifunctional applications to meet the needs of different fields.

[0134] The performance test of a high-strength, repairable polyurethane elastomer obtained in Examples 1 to 6 and Comparative Examples 1 to 3 was performed, and the results are shown in the following table:

[0135]

[0136]

[0137] The present invention provides a new preparation process for the application of high-strength repairable polyurethane elastomers, and expands the application field of high-strength repairable polyurethane elastomers. In Example 1, ethyl acetate is used as a solvent because its lower polarity contributes to the uniformity of the reaction and reduces the possibility of side reactions. At the same time, the dynamically reversible disulfide bonds and the evenly distributed polymer segments synergize to enable the material to efficiently perform fracture and recombination reactions at room temperature. Compared with other solvents, ethyl acetate has moderate volatility and can form a stable polymer network during the drying process, thereby giving the material higher mechanical strength and faster self-repair speed. In Comparative Examples 1-3, due to the lack of dynamically reversible disulfide bonds (such as 1,4-dibutylamine in Comparative Example 1 and diaminopyridine in Comparative Example 2), or the introduction of a rigid aromatic ring structure (such as 2,2-diaminodiphenyl disulfide in Comparative Example 3), the dynamic recombination ability of the molecular chain is limited, resulting in poor repair performance. In addition, the presence of aromatic rings also increases the cross-linking density of the material and has a certain effect on the elasticity of polyurethane.

[0138] It should be noted that in the above embodiments, as long as the technical solutions are not contradictory, they can be arranged and combined, and those skilled in the art can exhaust all possibilities based on the mathematical knowledge of arrangement and combination. Therefore, the present invention will no longer describe the technical solutions after arrangement and combination one by one, but it should be understood that the technical solutions after arrangement and combination have been disclosed by the present invention.

[0139] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A high-strength, repairable polyurethane elastomer, characterized in that: The high-strength and repairable polyurethane elastomer consists of a solvent, polytetramethylene ether glycol, diphenylmethane diisocyanate, dibutyltin dilaurate and cystamine dihydrochloride. The mass fraction of the solvent is 200 parts, the mass fraction of polytetramethylene ether glycol is 40 parts, the mass fraction of diphenylmethane diisocyanate is 10 parts, the mass fraction of dibutyltin dilaurate is 1.5 parts, and the mass fraction of cystamine dihydrochloride is 0.2-0.5 parts.

2. A high-strength, repairable polyurethane elastomer according to claim 1, characterized in that: The solvent is one or more of ethyl acetate, N,N-dimethylacetamide, N,N-dimethylformamide and dimethyl sulfoxide.

3. A high-strength, repairable polyurethane elastomer according to claim 1, characterized in that: The molecular weight of the polytetramethylene ether glycol is 2000.

4. A method for preparing a high-strength, repairable polyurethane elastomer, characterized in that: The steps include: Step 1: Place the solvent in a reaction vessel, heat and stir, and introduce nitrogen protection; Step 2: Add polytetramethylene ether glycol into a reaction container, and then drop diphenylmethane diisocyanate into the reaction container through a constant pressure dropping funnel; Step 3: After the dropwise addition is completed, dibutyltin dilaurate is added dropwise to react and generate a prepolymer. Step 4: After the prepolymer solution is cooled to room temperature, cystamine dihydrochloride is added dropwise, and the mixture is reheated and reacted again; Step 5: After the reaction is completed, the mixture is transferred to a vacuum device and the solvent is removed by evaporation to obtain a PUU elastomer; Step 6: Place the PUU elastomer in a vacuum environment at 80°C for post-treatment to ensure the performance stability and purity of the material.

5. The method for preparing a high-strength, repairable polyurethane elastomer according to claim 4, characterized in that: In the step 1, the stirring speed is 100 r / min and the temperature is raised to 80° C.

6. The method for preparing a high-strength, repairable polyurethane elastomer according to claim 4, characterized in that: The dropping time in the step 2 is 30 min.

7. The method for preparing a high-strength, repairable polyurethane elastomer according to claim 4, characterized in that: In the step 3, the reaction is carried out at a temperature of 80° C. for 1.5 hours.

8. The method for preparing a high-strength, repairable polyurethane elastomer according to claim 4, characterized in that: In the step 4, the mixture is heated to 40° C. and the reaction time is 2 hours.

9. The method for preparing a high-strength, repairable polyurethane elastomer according to claim 4, characterized in that: The post-treatment time in step six is ​​8 hours.

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