Tear-resistant functional chain extender, preparation and application thereof in tear-resistant polyurethane

Abstract

The invention discloses a tear-resistant functional chain extender, preparation and application of the tear-resistant functional chain extender in tear-resistant polyurethane, and belongs to the field of preparation of polyurethane raw materials. The anti-tear functional chain extender disclosed by the invention comprises an anti-tear structural unit and an auxiliary toughening structural unit, the tear-resistant polyurethane based on the natural amino acid derivative comprises multifunctional isocyanate, polyol, a tear-resistant functional chain extender and a catalyst. According to the tear-resistant polyurethane based on the natural amino acid derivative, the fracture toughness is greatly improved compared with 100-1000 J / m < 2 > of conventional polyurethane, and the fracture toughness of the polyurethane with the tear resistance enhanced through structural design can be improved by 1-2 orders of magnitude; meanwhile, the method has relatively high universality on selection of natural amino acids applied to the method.

Description

Technical Field

[0001] The invention belongs to the field of polyurethane raw material preparation, and mainly relates to an anti-tear functional chain extender, and its preparation and application in tear-resistant polyurethane. Background Art

[0002] Polyurethane is a polymer material invented by German chemist Bayer in the 1930s. It is a polymer with repeating units of carbamate in its main chain (AB). n Type block copolymer, where A and B represent the soft segment and hard segment of polyurethane, respectively. Due to the difference in hydrogen bonding and mutual solubility, the thermodynamic incompatibility of the soft segment and hard segment of polyurethane results in obvious separation of hard segment and soft segment in the polyurethane structure. This microphase separation gives this multiphase polymer good mechanical strength, elasticity, corrosion resistance and other characteristics, providing a strong performance foundation for the design core of polyurethane as a multifunctional material. Although most polyurethanes have good elasticity, once defects such as microcracks appear inside the material, these defects will still spread rapidly in the material system and form macroscopic defects, and significantly increase the safety risk of the material during use. The fracture toughness of conventional polyurethane is about 100 to 1000 J / m 2 .

[0003] In addition, with the development of the polyurethane industry, the use of petroleum-based polyols has increased significantly. At present, castor oil-based polyols have been studied and applied to a certain extent, while amino acids in bio-based raw materials have received relatively little attention in the field of polyurethane. On the one hand, the physical and chemical properties of amino acids themselves make it difficult to dissolve or disperse in non-aqueous systems; on the other hand, the amino group in amino acids is too active in reacting with isocyanate groups, making the reaction rate difficult to control. Therefore, liquefaction and reaction activity balance will be two technical problems that need to be urgently solved to solve the application of amino acids in polyurethane. Summary of the invention

[0004] The present invention is to solve the above technical problems and provide a tear-resistant functional chain extender, preparation and application thereof in tear-resistant polyurethane. The tear-resistant polyurethane based on natural amino acid derivatives prepared by the present invention has a fracture toughness of 100 to 1000 J / m compared with that of conventional polyurethane. 2 The polyurethane with enhanced tear resistance through structural design in the present invention has a greatly improved fracture toughness of 1 to 2 orders of magnitude higher; at the same time, the selection of natural amino acids used therein has great universality.

[0005] To solve the above problems, the present invention is implemented through the following technical solutions:

[0006] The first object of the present invention is:

[0007] Provided is a tear-resistant functional chain extender having a structure shown in formula (1):

[0008]

[0009] Among them, B 1 , B 2 is a tear-resistant structural unit, A is an auxiliary toughening structural unit, n represents the number of B1-A links, and its value is an integer from 0 to 99, and B1 and B2 may be the same or different;

[0010] The tear-resistant structural unit B 1 , B 2 It has the structure of formula (2):

[0011]

[0012] Among them RX - It is an anion of a natural amino acid derivative, Y + It is one or a combination of hydrogen ions, large-volume organic cations, and metal cations; R is a functional side group, m is the number of R, and its value is an integer of 0 to 5; X is a natural amino acid structural unit.

[0013] The tear-resistant functional chain extender of the present invention is further optimized as follows:

[0014] The auxiliary toughening structural unit A has a structure derived from: bisphenol A diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, glycerol diglycidyl ether, resorcinol diglycidyl ether, glycerol triglycidyl ether, trimethylolpropane triglycidyl ether, pentaerythritol tetraglycidyl ether, octa-(γ-glycidyl ether oxygen propyl) cage-type polysilsesquioxane, octa-(β-(3,4-epoxycyclohexyl)ethyl) cage-type polysilsesquioxane or a combination of the above.

[0015] The tear-resistant functional chain extender of the present invention is further optimized as follows:

[0016] The natural amino acid structural unit X is selected from the group consisting of glycine, alanine, valine, leucine, isoleucine, phenylalanine, threonine, glutamic acid, glutamine, aspartic acid, methionine, serine, tyrosine, cysteine, lysine, arginine, histidine, tryptophan, and proline, or a combination of the two.

[0017] The tear-resistant functional chain extender of the present invention is further optimized as follows:

[0018] The functional side group R is derived from one or a combination of n-butyl glycidyl ether, allyl glycidyl ether, 5-ethylhexyl glycidyl ether, phenyl ethylene oxide, phenyl glycidyl ether, cresol glycidyl ether, p-isobutylphenyl glycidyl ether methacrylate glycidyl ether, carbonyl glycidyl ether, benzyl glycidyl ether, and cardanol glycidyl ether. The functional side group R is used to adjust the mechanical properties and compatibility of the system.

[0019] The tear-resistant functional chain extender of the present invention is further optimized as follows:

[0020] The bulky organic cation is selected from: N,N'-dialkyl imidazolium cation, N-alkyl pyridinium cation, hydrogenated alkylamine cation, quaternary ammonium cation, or a combination thereof;

[0021] The metal cation is selected from the group consisting of lithium ion, sodium ion, potassium ion, magnesium ion, calcium ion, iron (III) ion, copper (II) ion, zinc (II) ion or a combination of the two.

[0022] The second object of the present invention is:

[0023] A method for preparing the aforementioned tear-resistant functional chain extender is provided, which comprises the following preparation steps:

[0024] S1. According to the required molar ratio, the natural amino acid structural unit X raw material is dissolved in water and neutralized with a combination of one or more of hydrogen ions, bulky organic cations, and metal cations at 50 ° C;

[0025] S2. After vacuum dehydration, if a reactant containing an auxiliary toughening structural unit A is required to participate in the reaction, the reactant containing an auxiliary toughening structural unit A is added to the dried product of step S1 and reacted at 80° C. for 180 min to prepare a tear-resistant functional chain extender without a functional side group;

[0026] S3. If it is necessary to introduce a functional side group, the functional side group R raw material is added and the reaction is continued at 80° C. for 90 min to prepare an anti-tear functional chain extender containing a functional side group.

[0027] The third invention object of the present invention is:

[0028] Provided is a tear-resistant polyurethane based on a natural amino acid derivative, comprising the following components in molar fractions:

[0029] 1.0 part of multifunctional isocyanate, 0-1.9 parts of polyol, 0.1-1.9 parts of the aforementioned tear-resistant functional chain extender, and 0-0.05 parts of catalyst.

[0030] The tear-resistant polyurethane is prepared in a solvent, N,N-dimethylformamide.

[0031] The tear-resistant polyurethane based on natural amino acid derivatives of the present invention is further optimized as follows:

[0032] It includes one or a combination of the following features:

[0033] The multifunctional isocyanate is selected from the group consisting of toluene-2,4-diisocyanate, toluene-2,5-diisocyanate, toluene-2,6-diisocyanate, m-phenylenediisocyanate, p-phenylenediisocyanate, 1,3-phenylenediisocyanate, L-lysine diisocyanate, 2,2,4-trimethylhexane diisocyanate, 1,4-cyclohexane diisocyanate, diphenylmethane 2,4'-diisocyanate, diphenylmethane 2,2'-diisocyanate, diphenylmethane 4,4'-diisocyanate, dicyclohexylmethane diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, poly(diphenylmethane diisocyanate), poly(hexamethylene diisocyanate), triphenylmethane triisocyanate, octa-(γ-isocyanatepropyl) cage-type polysilsesquioxane, or a combination thereof.

[0034] The polyol is selected from the group consisting of: 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, polyvinyl alcohol with a molecular weight of 400 to 2000, polyethylene glycol with a molecular weight of 400 to 2000, polypropylene glycol with a molecular weight of 400 to 2000, polytetramethylene glycol with a molecular weight of 850 to 2000, triricinoleylglycerol, and hydroxyl-terminated polydimethylsiloxane with a molecular weight of 1000, or a combination thereof;

[0035] The catalyst is selected from the group consisting of: dibutyltin dilaurate, dioctyltin dilaurate, stannous octoate, dibutyltin di(dodecyl sulfide), dioctyltin di(dodecyl sulfide), dimethyltin di(dodecyl sulfide), dibutyltin diacetate, dibutyltin dimercaptoacetate, di-n-butyltin oxide, dimethyltin dineodecanoate, dioctyltin dineodecanoate, dioctyltin dimercaptoacetate, dimethyltin dioleate, potassium isooctanoate, potassium acetate, potassium oleate, zinc isooctanoate, bismuth isooctanoate, pentanedione-zirconium complex, tetrabutyl titanate, and tetraisopropyl titanate, or a combination of the foregoing.

[0036] The fourth invention objective of the present invention is:

[0037] Provided is a method for preparing the aforementioned tear-resistant polyurethane based on natural amino acid derivatives:

[0038] According to the proportion, the multifunctional isocyanate and polyol with the catalyst added are dissolved in N,N-dimethylformamide, and reacted at 30-90°C for 0.2-6h. The reaction temperature is controlled to be 10-110°C, and the tear-resistant functional chain extender prepared by S1-S3 is added to the reaction system in 1-4 times and reacted for 0.2-6h. The solvent N,N-dimethylformamide is removed to prepare the tear-resistant polyurethane based on natural amino acid derivatives.

[0039] The tear-resistant polyurethane based on natural amino acid derivatives of the present invention obtains ionic liquids based on natural amino acid derivatives through modification and group modification. After such substances enter the main chain of polyurethane, the anionic and cationic structures will be suspended on the side chains due to electrostatic effects and attract each other to reduce energy, and finally a dynamic aggregation phase with a size of 1 to 100 nm can be formed in the system, which will greatly improve the tear resistance of the material. At the same time, the number of highly active NH bonds retained by the amino acids modified with side chains is controllable, and the reaction rate can also be artificially adjusted; in addition, the wide selection of structural units such as polyisocyanates, auxiliary toughening units and functionalized side chains makes the compatibility of the entire reaction system with different solvents and other types of polymers more designable.

[0040] The tear-resistant polyurethane based on natural amino acid derivatives of the present invention has considerable strength and elongation at break, and excellent tear resistance. Compared with conventional polyurethane, its fracture toughness can be improved by 1 to 2 orders of magnitude. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 Schematic diagram of the structural differences between the chain extenders in the examples of the present invention and the control examples. DETAILED DESCRIPTION

[0042] In order to make the application, technical scheme and advantages of the present invention more clear, the present invention is described in detail in conjunction with specific embodiments. It should be understood that the embodiments are only used to illustrate the present invention, but not to limit the protection scope of the present invention. All simple improvements to the preparation method of the present invention under the premise of the concept of the present invention belong to the protection scope of the present invention.

[0043] Example 1

[0044] A method for preparing tear-resistant polyurethane based on natural amino acid derivatives:

[0045] It comprises the following preparation steps:

[0046] (I) Preparation of tear-resistant functional chain extender S1:

[0047] 6mmol of glutamic acid was dissolved in water and neutralized with 3mmol of N-methyl-N'-octylimidazole hydroxide and 3mmol of lithium hydroxide at 50°C. After vacuum removal of water, the mixture was reacted with 12mmol of n-butyl glycidyl ether at 80°C to prepare the tear-resistant functional chain extender S1.

[0048] (II) Preparation of tear-resistant polyurethane PUS1:

[0049] 12 mmol of hexamethylene diisocyanate with 0.025 mmol of dibutyltin dilaurate added thereto and 6 mmol of polytetramethylene furan ether (molecular weight 1000) were dissolved in N,N-dimethylformamide, and reacted at 50°C for 40 min. After adding 4.5 mmol of tear-resistant functional chain extender S1, the reaction was continued at 60°C for 25 min, and N,N-dimethylformamide was removed to obtain tear-resistant polyurethane PUS1.

[0050] Comparative Example 1

[0051] (I) Preparation of control group chain extender C1:

[0052] 6mmol of glutamic acid reacts with 12mmol of n-butyl glycidyl ether in N,N-dimethylformamide at 80°C, and after removing excess N,N-dimethylformamide, chain extender C1 is prepared;

[0053] (ii) Control group polyurethane PUC1

[0054] 12 mmol of hexamethylene diisocyanate with 0.025 mmol of dibutyltin dilaurate added thereto and 6 mmol of polytetramethylene furan ether (molecular weight 1000) were dissolved in N,N-dimethylformamide, and reacted at 50°C for 40 min. After adding 4.5 mmol of chain extender C1, the reaction was continued at 60°C for 25 min, and N,N-dimethylformamide was removed to obtain polyurethane PUC1.

[0055] Example 2

[0056] A method for preparing tear-resistant polyurethane based on natural amino acid derivatives:

[0057] It comprises the following preparation steps:

[0058] (I) Preparation of tear-resistant functional chain extender S2:

[0059] 10mmol proline was neutralized with 8mmol trioctylamine in water at 50°C, and after vacuum removal of water, it was reacted with 5mmol 1,6-hexanediol diglycidyl ether at 80°C to prepare tear-resistant functional chain extender S2;

[0060] (II) Preparation of tear-resistant polyurethane PUS2:

[0061] 6 mmol of diphenylmethane 2,4'-diisocyanate and 6 mmol of diphenylmethane 4,4'-diisocyanate were dissolved in N,N-dimethylformamide and reacted with 9 mmol of tear-resistant functional chain extender S2 in a nitrogen atmosphere at 30°C for 60 min. After removing N,N-dimethylformamide, tear-resistant polyurethane PUS2 was obtained.

[0062] Comparative Example 2

[0063] (I) Preparation of control group chain extender C2:

[0064] 10 mmol of proline and 5 mmol of 1,6-hexanediol diglycidyl ether were reacted at 80°C to prepare chain extender C2;

[0065] (II) Preparation of polyurethane PUC2 of control group:

[0066] 6 mmol of diphenylmethane 2,4'-diisocyanate and 6 mmol of diphenylmethane 4,4'-diisocyanate were dissolved in N,N-dimethylformamide and reacted with 9 mmol of chain extender C2 at 30°C for 60 min in a nitrogen atmosphere. After removing N,N-dimethylformamide, polyurethane PUC2 was obtained.

[0067] Example 3

[0068] A method for preparing tear-resistant polyurethane based on natural amino acid derivatives:

[0069] It comprises the following preparation steps:

[0070] (I) Preparation of tear-resistant functional chain extender S3:

[0071] 6mmol lysine and 6mmol phenylalanine were neutralized with 6mmol N,N'-dimethylimidazole hydroxide and 3mmol copper oxide in water phase at 50°C; after vacuum dehydration, they were reacted with bisphenol A epoxy resin E51 containing 6mmol epoxy groups at 80°C for 180min; 6mmol allyl glycidyl ether was added and the reaction was continued for 90min to prepare tear-resistant functional chain extender S3;

[0072] (II) Preparation of tear-resistant polyurethane PUS3:

[0073] 12 mmol of isophorone diisocyanate with 0.04 mmol of dioctyltin dilaurate added thereto and 3 mmol of polyethylene glycol (molecular weight 400) were dissolved in N,N-dimethylformamide, reacted at 80°C for 240 min, then 2 mmol of tear-resistant functional chain extender S3 was added and the reaction was continued at 75°C for 45 min, and N,N-dimethylformamide was removed to obtain tear-resistant polyurethane PUS3.

[0074] Comparative Example 3

[0075] (I) Preparation of control group chain extender C3:

[0076] 6mmol of lysine and 6mmol of phenylalanine were reacted with bisphenol A type epoxy resin E51 containing 6mmol of epoxy groups at 80°C for 180min; then 6mmol of allyl glycidyl ether was added and the reaction was continued for 90min to prepare chain extender C3;

[0077] (II) Preparation of polyurethane PUC3 in the control group:

[0078] 12 mmol of isophorone diisocyanate with 0.04 mmol of dioctyltin dilaurate added thereto and 3 mmol of polyethylene glycol (molecular weight 400) were dissolved in N,N-dimethylformamide and reacted at 80°C for 240 min. Then, 2 mmol of chain extender C3 was added and the reaction was continued at 75°C for 45 min. N,N-dimethylformamide was removed to obtain polyurethane PUC3.

[0079] Performance Testing:

[0080] The above embodiment and the control example were compared in performance, and the specific method was as follows:

[0081] Ten specimens were taken from the films of six samples (PUS1, PUS2, PUS3, PUC1, PUC2, PUC3), respectively. The specifications of the specimens were Type 4 as specified in GB / T 528-92.

[0082] The specimens of each sample were divided into two groups of 5, 5 of which were used for conventional tensile tests and the other 5 for single-edge notch tests, and the corresponding stress-strain curve of each specimen was recorded.

[0083] Conventional tensile test conditions: room temperature (23±2°C); tensile rate of 50 mm / min.

[0084] Single-edge notch test: Use a razor blade to pre-crack the specimen in the center perpendicular to the length of the specimen, where the crack width does not exceed 80% of the width of the specimen test area, followed by a conventional tensile test. The single-edge notch test is used to calculate the fracture toughness (G c ), the fracture toughness calculation formula of the spline in this paper is as follows:

[0085]

[0086] Where α is the gap width, λ c is the elongation ratio at notch fracture, W cis the strain energy density when the crack starts to expand, which can be obtained from the original stress-strain curve in the definition domain [0,λ c ] is calculated by the integral within ].

[0087] The performance test results are shown in Table 1.

[0088] Table 1

[0089] project Sample name Elongation at break % Tensile strength / MPa <![CDATA[Fracture toughness / J.m -2 > Example 1 PUS1 1820 25.6 101250 Comparative Example 1 PUC1 903 17.1 935 Example 2 PUS2 286 18.5 15306 Comparative Example 2 PUC2 55 20.2 403 Example 3 PUS3 1245 15.0 34707 Comparative Example 3 PUC3 1560 9.5 2322

[0090] As can be seen from Table 1, the fracture toughness of the polyurethanes (PUS1, PUS2, PUS3) with the introduction of anti-tear mechanism is improved by 1 to 2 orders of magnitude compared with the corresponding control group polyurethanes (PUC1, PUC2, PUC3), while also having considerable elongation at break and tensile strength.

[0091] The difference between the embodiment and the control example is whether the chain extender unit is ionized, the synthesis method is different, and the final control variable is the structure. The structural difference of the chain extender in the embodiment and the control example is shown in the attached Figure 1 .

[0092] The present invention cannot describe all possible combinations; however, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0093] The experimental methods without specific conditions in the present invention are usually carried out under conventional conditions or conditions recommended by the manufacturer.

[0094] Unless otherwise stated, the various optimization technical solutions in the present invention can be combined with each other.

[0095] Unless otherwise indicated, percentages and parts are by weight.

[0096] Experimental methods without specific conditions specified in the instructions and examples are usually carried out under conventional conditions or conditions recommended by the manufacturers.

[0097] Unless otherwise defined, all professional and scientific terms used herein have the same meaning as those familiar to those skilled in the art. In addition, any method and material similar or equivalent to the described content can be applied to the method of the present invention.

Claims

1. A tear-resistant functional chain extender, characterized in that: The tear-resistant functional chain extender has a structure shown in formula (1): Wherein B1 and B2 are tear-resistant structural units, A is an auxiliary toughening structural unit, n represents the number of B1-A chain links, and its value is an integer of 0 to 99, and B1 and B2 may be the same or different; The tear-resistant structural units B1 and B2 have the structure of formula (2): Among them RX - It is an anion of a natural amino acid derivative, Y + It is one or a combination of hydrogen ions, large-volume organic cations, and metal cations; R is a functional side group, m is the number of R, and its value is an integer of 0 to 5; X is a natural amino acid structural unit.

2. The tear-resistant functional chain extender according to claim 1, characterized in that: The auxiliary toughening structural unit A has a structure derived from: bisphenol A diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, glycerol diglycidyl ether, resorcinol diglycidyl ether, glycerol triglycidyl ether, trimethylolpropane triglycidyl ether, pentaerythritol tetraglycidyl ether, octa-(γ-glycidyl ether oxygen propyl) cage-type polysilsesquioxane, octa-(β-(3,4-epoxycyclohexyl)ethyl) cage-type polysilsesquioxane or a combination of the above.

3. The tear-resistant functional chain extender according to claim 1, characterized in that: The natural amino acid structural unit X is selected from the group consisting of glycine, alanine, valine, leucine, isoleucine, phenylalanine, threonine, glutamic acid, glutamine, aspartic acid, methionine, serine, tyrosine, cysteine, lysine, arginine, histidine, tryptophan, and proline, or a combination of the two.

4. The tear-resistant functional chain extender according to claim 1, characterized in that: The structure of the functional side group R is derived from one or a combination of n-butyl glycidyl ether, allyl glycidyl ether, 5-ethylhexyl glycidyl ether, phenyl ethylene oxide, phenyl glycidyl ether, cresol glycidyl ether, p-isobutylphenyl glycidyl ether methacrylate glycidyl ether, carbonyl glycidyl ether, benzyl glycidyl ether, and cardanol glycidyl ether.

5. The tear-resistant functional chain extender according to claim 1, characterized in that: The bulky organic cation is selected from: N,N'-dialkyl imidazolium cation, N-alkyl pyridinium cation, hydrogenated trialkylamine cation, quaternary ammonium cation, or a combination thereof; The metal cation is selected from the group consisting of lithium ion, sodium ion, potassium ion, magnesium ion, calcium ion, iron (III) ion, copper (II) ion, zinc (II) ion or a combination of the two.

6. A method for preparing the tear-resistant functional chain extender according to claim 1, characterized in that: It comprises the following preparation steps: S1. According to the required molar ratio, the natural amino acid structural unit X raw material is dissolved in water and neutralized with a combination of one or more of hydrogen ions, bulky organic cations, and metal cations at 50 ° C; S2. After vacuum dehydration, if a reactant containing an auxiliary toughening structural unit A is required to participate in the reaction, the reactant containing the auxiliary toughening structural unit A is added to the dried product of step S1 and reacted at 80° C. for 180 min to prepare a tear-resistant functional chain extender without a functional side group; S3. If it is necessary to introduce a functional side group, the functional side group R raw material is added and the reaction is continued at 80° C. for 90 min to prepare an anti-tear functional chain extender containing a functional side group.

7. A tear-resistant polyurethane based on natural amino acid derivatives, characterized in that: It includes the following components in molar fractions: 1.0 part of multifunctional isocyanate, 0-1.9 parts of polyol, 0.1-1.9 parts of the tear-resistant functional chain extender according to claim 1, and 0-0.05 parts of catalyst.

8. The tear-resistant polyurethane based on natural amino acid derivatives according to claim 7, characterized in that: It includes one or a combination of the following features: The multifunctional isocyanate is selected from the group consisting of toluene-2,4-diisocyanate, toluene-2,5-diisocyanate, toluene-2,6-diisocyanate, m-phenylenediisocyanate, p-phenylenediisocyanate, 1,3-phenylenediisocyanate, L-lysine diisocyanate, 2,2,4-trimethylhexane diisocyanate, 1,4-cyclohexane diisocyanate, diphenylmethane 2,4'-diisocyanate, diphenylmethane 2,2'-diisocyanate, diphenylmethane 4,4'-diisocyanate, dicyclohexylmethane diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, poly(diphenylmethane diisocyanate), poly(hexamethylene diisocyanate), triphenylmethane triisocyanate, octa-(γ-isocyanatepropyl) cage-type polysilsesquioxane, or a combination thereof. The polyol is selected from the group consisting of: 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, polyvinyl alcohol with a molecular weight of 400 to 2000, polyethylene glycol with a molecular weight of 400 to 2000, polypropylene glycol with a molecular weight of 400 to 2000, polytetramethylene glycol with a molecular weight of 850 to 2000, triricinoleylglycerol, and hydroxyl-terminated polydimethylsiloxane with a molecular weight of 1000, or a combination thereof; The catalyst is selected from the group consisting of: dibutyltin dilaurate, dioctyltin dilaurate, stannous octoate, dibutyltin di(dodecyl sulfide), dioctyltin di(dodecyl sulfide), dimethyltin di(dodecyl sulfide), dibutyltin diacetate, dibutyltin dimercaptoacetate, di-n-butyltin oxide, dimethyltin dineodecanoate, dioctyltin dineodecanoate, dioctyltin dimercaptoacetate, dimethyltin dioleate, potassium isooctanoate, potassium acetate, potassium oleate, zinc isooctanoate, bismuth isooctanoate, pentanedione-zirconium complex, tetrabutyl titanate, and tetraisopropyl titanate, or a combination of the foregoing.

9. A method for preparing tear-resistant polyurethane based on natural amino acid derivatives according to claim 7, characterized in that: According to the proportion, the multifunctional isocyanate and polyol with the catalyst added are dissolved in N,N-dimethylformamide, and reacted at 30-90°C for 0.2-6h, and then the reaction temperature is controlled to be 10-110°C. The tear-resistant functional chain extender according to claim 1 is added to the reaction system in 1-4 times and reacted for 0.2-6h, and the solvent N,N-dimethylformamide is removed to prepare the tear-resistant polyurethane based on natural amino acid derivatives.

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