A glycosyl inducer with multiple supramolecular interactions, its preparation method and application

Abstract

This invention relates to the field of polymer material modification technology, specifically to a glycosyl inducer with multiple supramolecular interactions, its preparation method, and its application. The inducer uses a glycoside as a backbone, covalently links a pyrimidine derivative to it via isocyanate, and introduces a chlorine atom at the glycosyl terminus, exhibiting the synergistic effect of both chlorine-hydrogen bonds and N-H multiple hydrogen bonds. The preparation method includes three steps: isocyanate end-capping of the pyrimidine derivative, linking to the glycoside, and chloroacetyl chloride modification. This inducer is used for the thermoplastic modification of straw-based polysaccharides. After mixing with polysaccharide fibers and then kneading under shear conditions, a thermoplastic polysaccharide composite material is obtained. This inducer exhibits excellent compatibility with polysaccharides, effectively weakens intramolecular and intermolecular hydrogen bonds in polysaccharides, significantly improves the degree of thermoplasticization and tensile strength, and features a simple process, environmental friendliness, and applicability in food and pharmaceutical packaging, environmentally friendly home decoration, and cultural and creative materials.

Description

Technical Field

[0001] This invention relates to the field of polymer material modification technology, specifically to a glycosyl inducer with multiple supramolecular interactions, its preparation method, and its application. Background Technology

[0002] Polysaccharides are a major component of natural renewable resources such as straw, possessing advantages such as wide availability, low cost, biodegradability, and environmental friendliness, and have enormous application potential in food and pharmaceutical packaging, environmentally friendly materials, and cultural and creative products. However, the strong hydrogen bonds within and between polysaccharide molecules cause their melting temperature to be much higher than their thermal decomposition temperature, making them prone to thermal degradation under heat and shear, and difficult to thermoplasticize, severely limiting their industrial application.

[0003] To address the challenge of thermoplasticization of polysaccharides, existing technologies often employ glycosyl ionic liquids as inducing agents. These liquids weaken intramolecular and intermolecular hydrogen bonds through chlorine-hydrogen bonding, achieving initial thermoplasticization. However, these inducing agents rely solely on chlorine-hydrogen bonding, resulting in limited effectiveness in weakening the hydrogen bonds of polysaccharides. Consequently, the modified polysaccharides exhibit low thermoplasticization (only about 15%), poor mechanical properties (tensile strength mostly between 5-8 MPa), and a tendency to aggregate, making it difficult to meet practical processing and application requirements.

[0004] Multiple hydrogen bonds, as a strong supramolecular interaction, possess advantages such as high molecular structure designability, high interaction strength, and significant synergistic effects, and have attracted widespread attention in the fields of macromolecular self-assembly and intermolecular force regulation. If multiple hydrogen bonds can be combined with chlorine-hydrogen bonds to design a glycosyl inducer possessing both supramolecular effects, it is expected to further weaken the hydrogen bonding of polysaccharides and improve their thermoplasticization properties and processing stability. Currently, there are no reports on combining multiple hydrogen-bonded supramolecular networks with chlorine-hydrogen bonds for the thermoplasticization modification of polysaccharides, and there is also a lack of corresponding glycosyl inducer products with flexible raw material selection. Existing technologies use a limited variety of pyrimidines, sugars, and isocyanates as inducers, making it difficult to adapt to the modification needs of different polysaccharides and limiting the application flexibility of inducers. Summary of the Invention

[0005] The purpose of this invention is to provide a glycosyl inducer with multiple supramolecular interactions, its preparation method, and its application. The inducer uses a carbohydrate compound as the glycosyl backbone and a pyrimidine derivative as a multiple hydrogen bond donor. It covalently bonds a "chlorine-hydrogen supramolecular interaction fragment" and an "NH multiple hydrogen bond supramolecular network fragment" into a single unit, named UPy-suc (different combinations of carbohydrates / pyrimidines / isocyanates can be derived accordingly). The glycosyl inducer of this invention possesses the synergistic effect of both chlorine-hydrogen hydrogen bonds and multiple hydrogen bonds, enabling it to form strong multiple supramolecular interactions with polysaccharide macromolecules. This effectively weakens intramolecular and intermolecular hydrogen bonding in polysaccharides, significantly improving the thermoplasticization and processing stability of polysaccharides.

[0006] To achieve the above-mentioned technical objectives and effects, the present invention is implemented through the following technical solution: A glycosyl inducer with multiple supramolecular interactions, the chemical structure of which includes: A glycosyl backbone derived from carbohydrate compounds; A chlorine-hydrogen-bonded fragment, wherein the chlorine-hydrogen-bonded fragment comprises a chloroacetyl group linked to the glycosyl backbone via an ester bond or an ether bond; A multiple hydrogen-bonding fragment comprising a pyrimidine derivative residue containing an amino group (-NH2) and a carbonyl group (C=O). The glycosyl backbone and the multiple hydrogen-bonded fragment are covalently linked by a linking group formed by the reaction of isocyanate substances.

[0007] Furthermore, the carbohydrate compound is selected from one or more of sucrose, glucose, fructose, maltose, and lactose; The pyrimidine derivative is selected from one or more of 2-amino-4-carbonyl-5-hydroxyethyl-6-methylpyrimidine (HMAU), 2-amino-4-hydroxypyrimidine, 2-amino-5-methylpyrimidine, and 4-amino-2-carbonylpyrimidine.

[0008] Furthermore, the linking group formed by the reaction of isocyanate substances is derived from isocyanate substances, which are selected from one or more of hexamethylene diisocyanate (HDI), toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), and isophorone diisocyanate (IPDI).

[0009] On the other hand, the present invention proposes a method for preparing the above-mentioned glycosyl inducer with multiple supramolecular interactions, comprising the following steps: S1: React pyrimidine derivatives with isocyanates at 40~60℃ to obtain isocyanate-terminated pyrimidine derivatives; S2: Dissolve the carbohydrate compound in a polar aprotic solvent to prepare a solution, and react the solution with the isocyanate-terminated pyrimidine derivative obtained in step S1 at 50~70°C under stirring to obtain an intermediate containing a sugar hydroxyl group. S3: Add chloroacetyl chloride and a binding agent to the intermediate containing glycohydroxyl groups obtained in step S2, and react the chloroacetyl chloride with the glycohydroxyl groups at 30~50°C. The reaction product is then post-treated to obtain the glycosyl inducer.

[0010] Furthermore, the polar aprotic solvent in step S2 is dimethylacetamide, and the mass concentration of the carbohydrate compound solution is 10%~20%; the acid-binding agent in step S3 is triethylamine.

[0011] Furthermore, in step S1, the molar ratio of pyrimidine derivative to isocyanate is 1:(1.0~1.2); in step S2, the molar ratio of carbohydrate compound to isocyanate-terminated pyrimidine derivative is 1:(1.0~1.1); in step S3, the molar ratio of chloroacetyl chloride to intermediate is (2.0~2.2):1, and the molar ratio of triethylamine to chloroacetyl chloride is (1.1~1.2):1.

[0012] Furthermore, the reactions in steps S1 and S2 are both carried out under the protection of an inert gas, which is either nitrogen or argon.

[0013] On the other hand, this invention proposes the application of the above-mentioned glycosyl inducers with multiple supramolecular interactions in the thermoplasticization modification of polysaccharides.

[0014] Further, the method includes the following steps: mixing the glycosyl inducer with polysaccharide fibers at a molar ratio of (1~50):100, and kneading under shear conditions of 150~190℃ and 30~60rpm for 6~10min to obtain a thermoplastic polysaccharide composite material.

[0015] Furthermore, the polysaccharide fiber is a straw-based polysaccharide fiber, which is selected from one or more of wheat straw polysaccharide fibers, sugarcane straw polysaccharide fibers, and rice straw polysaccharide fibers.

[0016] The beneficial effects of this invention are: This invention achieves a dual synergistic weakening of intramolecular and intermolecular hydrogen bonds in polysaccharides through the covalent bonding of chlorine-hydrogen bonds and multiple hydrogen bond interactions within the same molecule. Specifically, the chlorine atom introduced onto the glycosyl backbone forms a chlorine-hydrogen bond with the hydroxyl hydrogen atoms of the polysaccharide, initially dissociating the original hydrogen bond association; the multiple hydrogen bond network formed by the self-assembly of amino and carbonyl groups in the pyrimidine derivative residues further competes for and replaces the polysaccharide's own hydrogen bonds. The synergistic effect of these two supramolecular interactions significantly enhances the mobility of the polysaccharide molecular chains, reduces melt flow resistance, and significantly improves thermoplasticization and tensile strength compared to single-acting inducers.

[0017] This invention uses a carbohydrate compound as the inducing agent backbone, which is similar in structure to the repeating unit of polysaccharides. When the two are blended, the interface wets well, and the inducing agent molecules are uniformly dispersed in the matrix, avoiding aggregation and phase separation. The inducing agent can fully exert its plasticizing and deassociation functions at the molecular level, ensuring that the composite material has a uniform texture and stable mechanical properties.

[0018] The preparation method of this invention operates at a reaction temperature of 40-70°C, requiring no high-temperature or high-pressure equipment; it can be completed in a conventional reaction vessel. The sugars, pyrimidine derivatives, and diisocyanates used are all readily available industrial raw materials, with stable sources and controllable costs. The solvent is recoverable during the reaction, and the byproduct hydrogen chloride is neutralized in situ by an acid-binding agent, resulting in no harmful emissions. The various examples demonstrate that different combinations of raw materials can stably yield high-purity products using the same process route, with yields all exceeding 85%. The process is highly versatile and easily scaled up for industrial applications.

[0019] This invention clarifies the selection range of various sugar compounds, pyrimidine derivatives, and isocyanates. Based on the differences in molecular weight distribution and impurities of polysaccharides from different sources, the raw material combination can be flexibly adjusted to control the flexibility, polarity, and compatibility of the inducer molecules, achieving a precise match between the inducer structure and modification performance, and expanding the applicable straw types and end-use scenarios.

[0020] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the synthetic route of the glycosyl inducer (different raw material combinations) described in this invention; Figure 2This is a schematic diagram of the multiple supramolecular interactions between molecules of the glycosyl inducer described in this invention.

[0023] Figure 3 The infrared spectra of the different glycosyl inducers prepared in Examples 1-4 are schematic diagrams.

[0024] Figure 4 S-TEM images and elemental analysis diagrams of the glycosyl inducers prepared in Example 1; (a) backscattered electron image, (b) oxygen element mapping that can represent polysaccharides, and (c) nitrogen element mapping that can represent pyrimidinones. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] Example 1

[0027] In this embodiment, the selected pyrimidine derivative is 2-amino-4-carbonyl-5-hydroxyethyl-6-methylpyrimidine, the sugar compound is sucrose, and the isocyanate is hexamethylene diisocyanate. The specific preparation steps are as follows: (1) Preparation of isocyanate-terminated pyrimidine derivatives: Under nitrogen protection, 0.1 mol of 2-amino-4-carbonyl-5-hydroxyethyl-6-methylpyrimidine was added to a reaction vessel, along with 50 mL of anhydrous ethanol as a solvent. After stirring to dissolve, 0.11 mol of hexamethylene diisocyanate was slowly added. The reaction temperature was controlled at 50 °C, and the reaction was stirred for 3 hours. After the reaction was completed, the solvent was removed by vacuum distillation to obtain the isocyanate-terminated pyrimidine derivative.

[0028] (2) Preparation of intermediates: 0.1 mol of sucrose was dissolved in 100 mL of dimethylacetamide to prepare a sucrose solution with a mass concentration of 15%. Under stirring at 300 rpm, the sucrose solution was slowly added dropwise at a rate of 1 drop / second to the isocyanate-terminated pyrimidine derivative obtained in step (1). The reaction temperature was controlled at 60 °C, and the reaction was continued with stirring for 4 hours to obtain an intermediate with sucrose residues at both ends and a pyrimidine fragment in the middle.

[0029] (3) Preparation of target inducer: 0.21 mol of chloroacetyl chloride and 0.23 mol of triethylamine were slowly added to the intermediate obtained in step (2) as an acid-binding agent. The reaction temperature was controlled at 40°C, and the reaction was stirred for 1.5 hours. After the reaction was completed, the precipitate was collected by filtration and washed four times alternately with anhydrous ethanol and deionized water, and then dried at 80°C for 5 hours. Finally, the target glycosyl inducer was purified by column chromatography using a mixed solvent of petroleum ether and ethyl acetate in a volume ratio of 3:1 as the eluent to obtain the glycosyl inducer in 88.6% yield.

[0030] Example 2

[0031] In this embodiment, the selected pyrimidine derivative is 2-amino-4-hydroxypyrimidine, the sugar compound is glucose, and the isocyanate is toluene diisocyanate. The specific preparation steps are as follows: (1) Preparation of isocyanate-terminated pyrimidine derivatives: Under argon protection, 0.1 mol of 2-amino-4-hydroxypyrimidine was added to a reaction vessel, along with 60 mL of anhydrous ethanol as a solvent. After stirring to dissolve, 0.1 mol of toluene diisocyanate was slowly added. The reaction temperature was controlled at 40 °C, and the reaction was stirred for 4 hours. After the reaction was completed, the solvent was removed by vacuum distillation to obtain the isocyanate-terminated pyrimidine derivative.

[0032] (2) Preparation of intermediates: 0.1 mol of glucose was dissolved in 80 mL of dimethylacetamide to prepare a 10% glucose solution. Under stirring at 400 rpm, the glucose solution was added dropwise at a rate of 1.5 drops / second to the isocyanate-terminated pyrimidine derivative obtained in step (1). The reaction temperature was controlled at 50 °C, and the reaction was continued with stirring for 5 hours to obtain an intermediate with glucose residues at both ends and a pyrimidine fragment in the middle.

[0033] (3) Preparation of target inducer: 0.2 mol of chloroacetyl chloride and 0.22 mol of triethylamine were slowly added to the intermediate obtained in step (2) as an acid-binding agent. The reaction temperature was controlled at 30°C, and the reaction was stirred for 2 hours. After the reaction was completed, the precipitate was collected by filtration and washed three times alternately with anhydrous ethanol and deionized water, and then dried at 90°C for 4 hours. Finally, the target glycosyl inducer was purified using the same column chromatography conditions as in Example 1, with a yield of 85.7%.

[0034] Example 3

[0035] In this embodiment, the selected pyrimidine derivative is 2-amino-5-methylpyrimidine, the sugar compound is maltose, and the isocyanate is diphenylmethane diisocyanate. The specific preparation steps are as follows: (1) Preparation of isocyanate-terminated pyrimidine derivatives: Under nitrogen protection, 0.1 mol of 2-amino-5-methylpyrimidine was added to a reaction vessel, along with 40 mL of anhydrous ethanol as a solvent. After stirring to dissolve, 0.12 mol of diphenylmethane diisocyanate was slowly added. The reaction temperature was controlled at 60 °C, and the reaction was stirred for 2 hours. After the reaction was completed, the solvent was removed by vacuum distillation to obtain the isocyanate-terminated pyrimidine derivative.

[0036] (2) Preparation of intermediates: 0.1 mol of maltose was dissolved in 120 mL of dimethylacetamide to prepare a 20% (w / w) maltose solution. Under stirring at 500 rpm, the maltose solution was added dropwise at a rate of 2 drops / second to the isocyanate-terminated pyrimidine derivative obtained in step (1). The reaction temperature was controlled at 70 °C, and the reaction was continued with stirring for 3 hours to obtain an intermediate with maltose residues at both ends and a pyrimidine fragment in the middle.

[0037] (3) Preparation of target inducer: 0.22 mol of chloroacetyl chloride and 0.24 mol of triethylamine were slowly added to the intermediate obtained in step (2) as an acid-binding agent. The reaction temperature was controlled at 50°C, and the reaction was stirred for 1 hour. After the reaction was completed, the precipitate was collected by filtration and washed four times alternately with anhydrous ethanol and deionized water, and then dried at 100°C for 6 hours. Finally, the target glycosyl inducer was purified using the same column chromatography conditions as in Example 1, with a yield of 87.9%.

[0038] Example 4

[0039] In this embodiment, the selected pyrimidine derivative is 4-amino-2-carbonylpyrimidine, the sugar compound is lactose, and the isocyanate is isophorone diisocyanate. The specific preparation steps are as follows: (1) Preparation of isocyanate-terminated pyrimidine derivatives: Under nitrogen protection, 0.1 mol of 4-amino-2-carbonylpyrimidine was added to a reaction vessel, along with 55 mL of anhydrous ethanol as a solvent. After stirring to dissolve, 0.11 mol of isophorone diisocyanate was slowly added. The reaction temperature was controlled at 55 °C, and the reaction was stirred for 2.5 hours. After the reaction was completed, the solvent was removed by vacuum distillation to obtain the isocyanate-terminated pyrimidine derivative.

[0040] (2) Preparation of intermediates: 0.1 mol of lactose was dissolved in 110 mL of dimethylacetamide to prepare a lactose solution with a mass concentration of 18%. Under stirring at 450 rpm, the lactose solution was added dropwise to the isocyanate-terminated pyrimidine derivative obtained in step (1) at a rate of 1.8 drops / second. The reaction temperature was controlled at 65 °C, and the reaction was continued with stirring for 3.5 hours to obtain an intermediate with lactose residues at both ends and a pyrimidine fragment in the middle.

[0041] (3) Preparation of target inducer: 0.215 mol of chloroacetyl chloride and 0.235 mol of triethylamine were slowly added to the intermediate obtained in step (2) as an acid-binding agent. The reaction temperature was controlled at 45°C, and the reaction was stirred for 1.2 hours. After the reaction was completed, the precipitate was collected by filtration and washed four times alternately with anhydrous ethanol and deionized water, and then dried at 95°C for 5 hours. Finally, the target glycosyl inducer was purified under the same column chromatography conditions as in Example 1, with a yield of 89.5%.

[0042] Example 5: Application of Example 1 This application example demonstrates the process of thermoplasticizing wheat straw polysaccharides using the glycosyl inducer of the present invention.

[0043] Pretreatment of wheat straw: The wheat straw is mechanically crushed and ground, passed through a 200-mesh standard sieve, and the sieve material is collected and washed twice with water to remove impurities. Then it is dried at 80℃ to constant weight to obtain wheat straw polysaccharide fiber.

[0044] Preparation of the composite system: The above-mentioned wheat straw polysaccharide fiber and the glycosyl inducer prepared in Example 2 were added to a high-speed mixer at a molar ratio of 100:10 and stirred evenly. The mixture was transferred to a torque rheometer and kneaded for 8 minutes at 170°C and 45 rpm to obtain the thermoplastic polysaccharide composite material.

[0045] Example 6: Application of Example 2 This application example demonstrates the process of thermoplasticizing sugarcane straw polysaccharides using the glycosyl inducer of the present invention.

[0046] Sugarcane straw was subjected to the same pretreatment operation as in Example 5 to obtain sugarcane straw polysaccharide fiber.

[0047] The sugarcane straw polysaccharide fibers described above were mixed with the glycosyl inducer prepared in Example 3 at a molar ratio of 100:12. The mixture was then added to a torque rheometer and kneaded for 8 minutes at 170°C and 45 rpm under shear conditions to obtain a thermoplastic polysaccharide composite material.

[0048] Example 7: Comparison of Application Examples To verify the technical effect of the present invention, a sucrose-based ionic liquid disclosed in the prior art was used as a control inducer. Wheat straw polysaccharide was thermoplasticized and modified according to the same process conditions and dosage as in Application Example 1 to prepare a control composite material.

[0049] Performance Testing and Evaluation The composite materials obtained in application examples 1 and 2 and the comparative application examples were subjected to performance tests. The test methods are as follows: Thermoplasticization degree: tested using a static thermomechanical analyzer.

[0050] Tensile strength: Tested using a universal testing machine according to GB / T 1040 standard.

[0051] Surface hardness: Tested using a Shore D hardness tester according to GB / T 2411 standard.

[0052] The test results are summarized in Table 1.

[0053] Table 1. Performance test results of thermoplastic polysaccharide composites As can be seen from the data in Table 1, compared with the comparative example using sucrose-based ionic liquids, the thermoplastic polysaccharide composite material prepared using the glycosyl inducer described in this invention exhibits significantly improved thermoplasticization degree, tensile strength, and surface hardness. The thermoplasticization degree exceeds 15%, the tensile strength exceeds 10 MPa, and the surface hardness exceeds 45D. This fully demonstrates that the synergistic effect of the chlorine-hydrogen bonds and multiple hydrogen bonds in the inducer of this invention can more effectively weaken the intramolecular and intermolecular hydrogen bonds of polysaccharides, thereby significantly improving their thermoplasticization processing properties and mechanical properties.

[0054] In summary, this invention proposes a glycosyl inducer with multiple supramolecular interactions, its preparation method, and its applications. The inducer uses a glycosyl compound as a backbone, covalently links a pyrimidine derivative to it via isocyanate, and introduces a chlorine atom at the glycosyl terminus, exhibiting the synergistic effect of both chlorine-hydrogen bonds and NH multiple hydrogen bonds. The preparation method includes three steps: isocyanate end-capping of the pyrimidine derivative, linking to the glycosyl compound, and chloroacetyl chloride modification. This inducer is used for the thermoplastic modification of straw-based polysaccharides. After mixing with polysaccharide fibers, it is kneaded under shear conditions to obtain a thermoplastic polysaccharide composite material. This inducer exhibits excellent compatibility with polysaccharides, effectively weakens intramolecular and intermolecular hydrogen bonds in polysaccharides, significantly improves the degree of thermoplasticization and tensile strength, and features a simple process, environmental friendliness, and applicability in food and pharmaceutical packaging, environmentally friendly home decoration, and cultural and creative materials.

[0055] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A glycosyl inducer with multiple supramolecular interactions, characterized in that, Its chemical structure includes: A glycosyl backbone derived from carbohydrate compounds; A chlorine-hydrogen-bonded fragment, wherein the chlorine-hydrogen-bonded fragment comprises a chloroacetyl group linked to the glycosyl backbone via an ester bond or an ether bond; A multiple hydrogen-bonding fragment, wherein the multiple hydrogen-bonding fragment comprises a pyrimidine derivative residue, wherein the pyrimidine derivative contains an amino group and a carbonyl group; The glycosyl backbone and the multiple hydrogen-bonded fragment are covalently linked by a linking group formed by the reaction of isocyanate substances.

2. The glycosyl inducer as described in claim 1, characterized in that, The carbohydrate compound is selected from one or more of sucrose, glucose, fructose, maltose, and lactose; The pyrimidine derivative is selected from one or more of 2-amino-4-carbonyl-5-hydroxyethyl-6-methylpyrimidine, 2-amino-4-hydroxypyrimidine, 2-amino-5-methylpyrimidine, and 4-amino-2-carbonylpyrimidine.

3. The glycosyl inducer as described in claim 1 or 2, characterized in that, The linking group formed by the reaction of isocyanate substances is derived from isocyanate substances, which are selected from one or more of hexamethylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, and isophorone diisocyanate.

4. A method for preparing the glycosyl inducer with multiple supramolecular interactions as described in any one of claims 1 to 3, characterized in that, Includes the following steps: S1: React pyrimidine derivatives with isocyanates at 40~60℃ to obtain isocyanate-terminated pyrimidine derivatives; S2: Dissolve the carbohydrate compound in a polar aprotic solvent to prepare a solution, and react the solution with the isocyanate-terminated pyrimidine derivative obtained in step S1 at 50~70°C under stirring to obtain an intermediate containing a sugar hydroxyl group. S3: Add chloroacetyl chloride and a binding agent to the intermediate containing glycohydroxyl groups obtained in step S2, and react the chloroacetyl chloride with the glycohydroxyl groups at 30~50°C. The reaction product is then post-treated to obtain the glycosyl inducer.

5. The preparation method according to claim 4, characterized in that, The polar aprotic solvent in step S2 is dimethylacetamide, and the mass concentration of the carbohydrate compound solution is 10%~20%; the acid-binding agent in step S3 is triethylamine.

6. The preparation method according to claim 4, characterized in that, In step S1, the molar ratio of pyrimidine derivative to isocyanate is 1:(1.0~1.2); in step S2, the molar ratio of carbohydrate compound to isocyanate-terminated pyrimidine derivative is 1:(1.0~1.1); in step S3, the molar ratio of chloroacetyl chloride to intermediate is (2.0~2.2):1, and the molar ratio of triethylamine to chloroacetyl chloride is (1.1~1.2):

1.

7. The preparation method according to claim 4, characterized in that, The reactions in steps S1 and S2 are both carried out under the protection of an inert gas, which is either nitrogen or argon.

8. The application of the glycosyl inducer with multiple supramolecular interactions as described in any one of claims 1 to 3 in the thermoplasticization modification of polysaccharides.

9. The application as described in claim 8, characterized in that, Includes the following steps: The glycosyl inducer and polysaccharide fiber are mixed in a molar ratio of (1~50):100 and kneaded under shear conditions of 150~190℃ and 30~60rpm for 6~10min to obtain a thermoplastic polysaccharide composite material.

10. The application as described in claim 9, characterized in that, The polysaccharide fiber is a straw-based polysaccharide fiber, which is selected from one or more of wheat straw polysaccharide fiber, sugarcane straw polysaccharide fiber, and rice straw polysaccharide fiber.

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