Biological plastic based on cellulose ether eutectic solvent and synthetic method thereof

Abstract

The invention discloses a bioplastic based on a cellulose ether eutectic solvent and a synthetic method of the bioplastic. The synthetic method comprises the following steps: preparing the cellulose ether eutectic solvent from a cellulose ether hydrogen bond donor and a hydrophobic phenol hydrogen bond acceptor according to a predetermined mass ratio under a certain temperature condition; then carrying out homogeneous dynamic boron-oxygen bond chemical modification on the cellulose ether in the deep eutectic solvent; and finally, adding a cellulose ether eutectic solvent mixed solution containing a polymerizable monomer, uniformly mixing the two solutions, and standing at a certain temperature for a certain time to prepare the bioplastic. In the preparation process, no initiator or catalyst is needed, no organic solvent or VOC is involved, the process is simple, green and environment-friendly, and the cost is low; the prepared bioplastic has excellent optical properties and mechanical properties, and also has the characteristics of recoverability and degradability.

Description

Technical Field

[0001] The invention relates to the field of bioplastic materials, and in particular to a bioplastic based on a cellulose ether low eutectic solvent and a synthesis method thereof. Background Art

[0002] As non-renewable resources are increasingly depleted worldwide, the development of green and sustainable materials has become an urgent need. As a recognized environmentally friendly material, cellulose has become an ideal choice for replacing petroleum-based resources to prepare high-value-added materials due to its advantages such as low cost, wide sources, easy degradation and renewability. Paper made from natural cellulose fibers has the characteristics of strong flexibility, light weight, high thermal stability, renewability and biodegradability, and is therefore considered a potential candidate for plastic replacement. However, the polyhydroxy structure of cellulose gives it strong hydrophilicity, and compared with traditional plastics, the porous structure, low wet strength and poor barrier properties of paper to water vapor and oxygen make it difficult to directly use it as a plastic substitute. By modifying the surface of paper, such as coating with waterproof coating, laminating or composite nanofillers and natural polymers, its water vapor barrier properties can be significantly improved. However, these paper-based composite materials still face limitations such as low recyclability, high cost and long preparation cycle.

[0003] In recent years, researchers have tried to develop high-performance cellulose products and realize their high-value utilization by chemically modifying the molecular structure of cellulose from a molecular scale. However, there are strong intramolecular and intermolecular hydrogen bonds inside the cellulose molecule, which usually requires the use of a large amount of solvents in the modification process and involves complex problems of subsequent separation and recovery. Therefore, the development of cellulose-based materials with excellent comprehensive performance, simple processing, recyclability and reusability is still a challenge that needs to be solved.

[0004] Deep Eutectic Solvents (DES) have attracted much attention in the fields of green solvents and functional material synthesis in recent years due to their simple preparation, extremely low vapor pressure, easy recovery, and strong dissolution ability for ionic and non-ionic compounds. DES is composed of a hydrogen bond acceptor and a hydrogen bond donor. The components form an electron delocalized structure through hydrogen bonding, resulting in a significant decrease in the melting point of the mixture compared to single components, showing an enthalpy-driven negative deviation from thermodynamic ideality. Due to the diverse selection of molecular structures of hydrogen bond donors and acceptors, DES is also known as "designer solvents". Based on these characteristics, researchers have tried to use DES as a green solvent for cellulose to prepare high-value-added products. However, despite optimization through means such as molecular structure design, ultrasonic assistance, or addition of co-solvents, the solubility of cellulose in DES is still relatively limited. Compared with traditional non-derivatized solvents such as N-methylmorpholine-N-oxide (solubility up to ~30 wt.%) and ionic liquids (>20 wt.%), the dissolution ability of DES for cellulose is still low.

[0005] The dissolution of cellulose is essentially a process of hydrogen bond breakage. An ideal solvent should have the ability to effectively interrupt the intra- and intermolecular hydrogen bonds of cellulose. However, taking common DES (such as choline chloride / urea solvent) as an example, although its components can form hydrogen bonds with cellulose, the dense hydrogen bond network among the internal components of DES limits its interaction with cellulose molecules, resulting in insufficient permeability to cellulose. The competition between the hydrogen bonds within DES and the hydrogen bonds between DES-cellulose ultimately reduces the solubility of cellulose in DES, and this limitation also becomes a bottleneck in the preparation of high-value-added cellulose-based functional materials using DES.

[0006] Existing studies have shown that the traditional method of dissolving cellulose with DES is difficult to balance the hydrogen bonds within DES and the hydrogen bonds between DES-cellulose. When cellulose is added to DES as a solute, it obtains the hydrogen bond interaction with DES through competition, which significantly limits its solubility. If the idea is changed to make cellulose directly participate in the construction of deep eutectic solvents as a component of DES, the hydrogen bond competition brought by the traditional solute role can be avoided, thus achieving a homogeneous solvent of cellulose at the molecular scale in one step. On this basis, by chemically modifying (such as introducing dynamic chemical bonds) the cellulose molecules for functional modification, cellulose-based adaptive functional materials can be conveniently prepared. At this time, the key lies in whether the cellulose molecules can be designed as hydrogen bond donors or acceptors that conform to the characteristics of DES components.

[0007] In addition, from the perspective of material design, researchers have also explored using DES as a dispersion medium for cellulose, achieving chemical cross-linking by introducing monomers to prepare enhanced cellulose-based functional materials; or in-situ chemically modifying the cellulose dispersed in DES to improve the mechanical properties of cellulose-based gel materials by grafting active monomers. However, these materials usually exhibit strong hydrophilicity and still have a gap in performance compared with traditional synthetic plastics. At the same time, the cellulose-based polymer network synthesized based on this solvent is difficult to depolymerize under conventional conditions, posing challenges to the degradation, recycling, and reuse of materials. Summary of the Invention

[0008] Object of the Invention: The present invention aims to provide a degradable, recyclable, and transparent bioplastic based on cellulose ether deep eutectic solvent and its synthesis method.

[0009] Technical Solution: The synthesis method of the bioplastic based on cellulose ether deep eutectic solvent according to the present invention includes the following steps:

[0010] Step S1: Prepare a cellulose ether deep eutectic solvent by mixing a cellulose ether hydrogen bond donor and a hydrophobic phenolic hydrogen bond acceptor in a mass ratio of 1:3 to 1:9 at 60 - 90 °C.

[0011] Step S2: Add an active intermediate containing an isocyanate group to the cellulose ether deep eutectic solvent obtained in Step S1 and react at room temperature for 1 - 4 h.

[0012] Step S3: Add a small molecule substance containing a phenylboronic acid group to the mixed solvent obtained in Step S2 and stir at room temperature for 24 - 48 h to obtain a mixture denoted as Solution A.

[0013] Step S4: Prepare a cellulose ether deep eutectic solvent according to Step S1, add a polymerizable monomer and mix evenly to obtain a mixture denoted as Solution B; wherein, the mass ratio of the polymerizable monomer to the cellulose ether deep eutectic solvent is 0.5:1 to 1.5:1.

[0014] Step S5: Mix Solution A obtained in Step S3 and Solution B obtained in Step S4 evenly and let it stand at 60 - 90 °C for 8 - 12 h to obtain a degradable, recyclable, and transparent bioplastic.

[0015] Preferably, in Step S1, the cellulose ether hydrogen bond donor is one or more of methyl cellulose, ethyl cellulose, and methyl ethyl cellulose.

[0016] Preferably, in Step S1, the hydrophobic phenolic hydrogen bond acceptor is one or more of thymol, carvacrol, vanillin, and eugenol.

[0017] Preferably, in step S2, the active intermediate containing an isocyanate group is one or more of isophorone diisocyanate, cyclohexane-1,4-diisocyanate, 4,4'-methylenebis(phenyl isocyanate), and 4,4-diisocyanatodicyclohexylmethane.

[0018] Preferably, in step S3, the small molecule substance containing a phenylboronic acid group is one or more of 3-carboxyphenylboronic acid, 4-carboxyphenylboronic acid, 2-aminophenylboronic acid, 3-aminophenylboronic acid, and 4-aminophenylboronic acid.

[0019] Preferably, in step S4, the polymerizable monomer is one or more of 2-hydroxyethyl acrylate, 2-hydroxypropyl methacrylate, 2-phenoxyethyl acrylate, isobornyl acrylate, and benzyl acrylate.

[0020] The bioplastic based on the cellulose ether deep eutectic solvent of the present invention is prepared by the above synthesis method.

[0021] Mechanism: Due to the rich hydroxyl functional groups, cellulose molecules theoretically have the potential to act as macromolecular hydrogen bond donors. However, the dense intramolecular and intermolecular hydrogen bonds within it limit its hydrogen bond supply ability. If its hydrogen bond supply ability is enhanced through appropriate molecular structure modification and combined with a matching hydrogen bond acceptor, a cellulose deep eutectic solvent at the molecular scale can be directly constructed without an external solvent. Further, by chemically modifying cellulose using this homogeneous solvent, a cellulose-based bioplastic can be constructed at the molecular level. Cellulose ether can significantly regulate its hydrogen bond supply ability through etherification modification and combine with different hydrogen bond acceptors through changes in functional groups and degrees of substitution to prepare a cellulose ether deep eutectic solvent. This solvent can be used as a medium for in-situ chemical modification to construct a cellulose-based dynamic self-adaptive material through an integrated design of supramolecular interaction and dynamic chemical modification.

[0022] Beneficial effects: Compared with the prior art, the significant advantages of the present invention are as follows: 1. Without the intervention of any external solvent, the present invention prepares cellulose ether deep eutectic solvents solely relying on hydrogen bonding between components, and uses it as an integrated green medium for cellulose structure modification and functional application at the molecular scale, providing a new idea for the development of cellulose-based bioplastic materials; 2. Both the cellulose ether hydrogen bond donor and the hydrophobic phenolic hydrogen bond acceptor in the cellulose ether deep eutectic solvent adopted in the present invention are natural biomass and its derivative components, and no organic solvents and VOCs are generated during the preparation process, making the preparation method and the resulting bioplastics environmentally friendly, simple in process, and green and low-cost; 3. The present invention utilizes the cellulose ether deep eutectic solvent to conduct homogeneous dynamic chemical modification (such as boron-oxygen bond chemical modification) on the cellulose ether hydrogen bond donor, and no catalyst is required for this process; 4. No initiator needs to be added during the synthesis process of the bioplastic of the present invention, and the self-polymerization crosslinking of polymerizable monomers is achieved relying on the high reactivity within the system; 5. The transparent bioplastic prepared by the present invention has excellent optical and mechanical properties and can be spontaneously repaired by hot pressing after fracture; 6. The bioplastic prepared by the present invention can still maintain good mechanical properties even after up to 20 times of recycling treatment; 7. The bioplastic prepared by the present invention can be spontaneously degraded in the natural environment, and its complete degradation period is about 3 months; 8. The bioplastic prepared by the present invention has broad application prospects in the fields of future intelligent packaging, degradable and recyclable products, etc. Description of the Drawings

[0023] Figure 1 Synthesis route diagram of the bioplastic prepared in Example 1;

[0024] Figure 2 Infrared spectrum diagram after the dynamic chemical modification involved in the process of preparing the bioplastic in Example 1;

[0025] Figure 3 Optical photograph of the bioplastic prepared in Example 2;

[0026] Figure 4 Ultraviolet-visible light transmittance curve diagram of the bioplastic prepared in Example 2;

[0027] Figure 5 Optical photographs of the puncture resistance demonstration and lifting of heavy objects of the bioplastic prepared in Example 3;

[0028] Figure 6 DSC curve diagram of the bioplastics prepared in Examples 1-5;

[0029] Figure 7 Stress-strain curve diagram of the bioplastics prepared in Examples 1-5;

[0030] Figure 8 The stress-strain curve diagrams of the bioplastic prepared in Example 4 after being soaked underwater for 1 day and 7 days;

[0031] Figure 9 The stress-strain curve diagram of the bioplastic prepared in Example 5 after hot pressing and welding;

[0032] Figure 10 The optical photo of the water-filled packaging bag prepared from the bioplastic prepared in Example 5 by hot pressing and welding;

[0033] Figure 11 The stress curve diagram of the bioplastic prepared in Example 3 after hot pressing and recycling;

[0034] Figure 12 The optical photo of the bioplastic prepared in Example 5 degrading outdoors. Specific embodiments

[0035] The present invention will be further described below with reference to the accompanying drawings.

[0036] Example 1

[0037] A synthesis method of a bioplastic based on a cellulose ether deep eutectic solvent, comprising the following steps:

[0038] Step S1: Weigh 1 g of ethyl cellulose and 9 g of thymol, with a mass ratio of 1:9, stir at 60 °C until clear and transparent, and then take it out and cool it to room temperature to complete the preparation of the cellulose ether deep eutectic solvent;

[0039] Step S2: Add 0.6873 g of isophorone diisocyanate to the cellulose ether deep eutectic solvent prepared in Step S1, and react at room temperature for 1 h;

[0040] Step S3: Add 0.4234 g of 3-aminophenylboronic acid to the mixed solvent prepared in Step S2, and stir at room temperature for 24 h; the mixture obtained in the above step is denoted as solution A;

[0041] Step S4: Prepare the cellulose ether deep eutectic solvent according to the method of Step S1, and then add 5 g of hydroxyethyl acrylate and mix evenly; the mixture obtained in the above step is denoted as solution B;

[0042] Step S5: Mix the solution A prepared in Step S3 and the solution B prepared in Step S4 evenly, and let it stand at 90 °C for 8 h to prepare a degradable and recyclable transparent bioplastic.

[0043] Such as Figure 2As shown, the infrared spectrum of the cellulose ether deep eutectic solvent prepared by the dynamic chemical modification in Steps S1 - S3 of Example 1. Comparing with the infrared spectrum of the cellulose ether deep eutectic solvent prepared in Step S1, after introducing isophorone diisocyanate in Step S2, a characteristic absorption peak of the -N=C=O functional group was found at 2267 cm -1 and a characteristic absorption peak of the -C=O functional group was found at 1717 cm -1 , indicating that isophorone diisocyanate reacted with the -OH functional group in the components of the cellulose ether deep eutectic solvent; moreover, after introducing 3-aminophenylboronic acid in Step S3, the absorption peak intensity of the -N=C=O functional group at 2267 cm -1 decreased significantly, which indicates that the -NH2 in 3-aminophenylboronic acid effectively reacted with the -N=C=O functional group, greatly consuming the content of the -N=C=O functional group in the system. In addition, a characteristic absorption peak of -NH was also found at 1660 cm -1 and a characteristic absorption peak of the phenyl group was found at 711 cm -1 . The above evidence indicates that 3-aminophenylboronic acid was effectively grafted onto the components in the cellulose ether deep eutectic solvent through isophorone diisocyanate.

[0044] As Figure 6 shown, the glass transition temperature of the bioplastic obtained in Example 1 was 26.92 °C. As Figure 7 shown, the deformation of the bioplastic obtained in Example 1 under stress was about 37%, and the tensile strength was about 5 MPa, showing good mechanical properties.

[0045] Example 2

[0046] A synthesis method of a bioplastic based on cellulose ether deep eutectic solvent, comprising the following steps:

[0047] Step S1: Weigh 1 g of methyl cellulose and 8 g of carvacrol, with a mass ratio of 1:8, stir at 90 °C until clear and transparent, and then take it out and cool it to room temperature to complete the preparation of the cellulose ether deep eutectic solvent;

[0048] Step S2: Add 0.511 g of cyclohexane-1,4-diisocyanate to the cellulose ether deep eutectic solvent prepared in Step S1 and react at room temperature for 4 h;

[0049] Step S3: Add 0.513 g of 3-carboxyphenylboronic acid to the mixed solvent prepared in Step S2 and stir at room temperature for 48 h; the mixture obtained above is denoted as Solution A;

[0050] Step S4: Prepare the cellulose ether eutectic solvent according to the method of Step S1, then add 9 g of hydroxypropyl methacrylate and mix evenly; the mixture obtained in the above step is denoted as Solution B;

[0051] Step S5: Mix the Solution A prepared in Step S3 and the Solution B prepared in Step S4 evenly, and let it stand at 60 °C for 12 h to prepare a degradable and recyclable transparent bioplastic.

[0052] As Figure 3 and Figure 4 shown, the optical photograph and ultraviolet-visible light transmittance curve of the degradable and recyclable transparent bioplastic prepared by the method of Example 2. The bioplastic can be processed into the shape of a leaf, and at the same time shows excellent optical transmittance, with an average optical transmittance of about ~85%; as Figure 6 shown, the glass transition temperature of the bioplastic obtained in Example 2 is 25.23 °C; as Figure 7 shown, the tensile deformation of the bioplastic obtained in Example 2 under stress is about 35%, and the tensile strength is about 9 MPa, showing good mechanical properties.

[0053] Example 3

[0054] A synthesis method of a bioplastic based on cellulose ether eutectic solvent, comprising the following steps:

[0055] Step S1: Weigh 1 g of ethyl methyl cellulose and 5 g of vanillin, with a mass ratio of 1:5, stir at 90 °C until clear and transparent, and then take it out and cool it to room temperature to complete the preparation of the cellulose ether eutectic solvent;

[0056] Step S2: Add 0.751 g of 4,4'-methylenebis(phenyl isocyanate) to the cellulose ether eutectic solvent prepared in Step S1 and react at room temperature for 2 h;

[0057] Step S3: Add 0.513 g of 4-carboxyphenylboronic acid to the mixed solvent prepared in Step S2 and stir at room temperature for 24 h; the mixture obtained in the above step is denoted as Solution A;

[0058] Step S4: Prepare the cellulose ether eutectic solvent according to the method of Step S1, then add 9 g of 2-phenoxyethyl acrylate and mix evenly; the mixture obtained in the above step is denoted as Solution B;

[0059] Step S5: Mix the Solution A prepared in Step S3 and the Solution B prepared in Step S4 evenly, and let it stand at 80 °C for 12 h to prepare a degradable and recyclable transparent bioplastic.

[0060] As Figure 5As shown, the optical photograph of the surface of the degradable and recyclable transparent bioplastic prepared by the method of Example 3 is punctured with an iron sharp object. As Figure 5 shown in (a) of Figure 5 , even if the bioplastic is greatly deformed, after the sharp object is withdrawn, only weak indentations are left on the surface and it is not punctured, showing excellent puncture resistance;

[0061] As Figure 6 shown, the glass transition temperature of the bioplastic obtained in Example 3 is 28.60 °C; as Figure 7 shown, the tensile deformation of the bioplastic obtained in Example 3 under stress is about 25%, and the tensile strength is about 14 MPa, showing good mechanical properties.

[0062] As Figure 11 shown, the bioplastic obtained in Example 3 can be recycled by hot pressing after being shredded. The hot pressing temperature is 150 °C and the pressure is 1 MPa; and it can still maintain good mechanical properties after being recycled up to 20 times.

[0063] Example 4

[0064] A synthesis method of a bioplastic based on a cellulose ether deep eutectic solvent, comprising the following steps:

[0065] Step S1: Weigh 1 g of ethyl cellulose and 3 g of eugenol, and the mass ratio of the two is 1:3. Stir at 90 °C until clear and transparent, and then take it out and cool it to room temperature to complete the preparation of the cellulose ether deep eutectic solvent;

[0066] Step S2: Add 0.751 g of 4,4'-diisocyanatodicyclohexylmethane to the cellulose ether deep eutectic solvent prepared in Step S1, and react at room temperature for 4 h;

[0067] Step S3: Add 0.4234 g of 2-aminophenylboronic acid to the mixed solvent prepared in Step S2, and stir at room temperature for 48 h; the mixture obtained in the above step is denoted as solution A;

[0068] Step S4: Prepare the cellulose ether deep eutectic solvent according to the method of Step S1, and then add 4 g of isobornyl acrylate and mix evenly; the mixture obtained in the above step is denoted as solution B;

[0069] Step S5: Mix the solution A prepared in Step S3 and the solution B prepared in Step S4 evenly, and let it stand at 90 °C for 12 h to prepare a degradable and recyclable transparent bioplastic.

[0070] AsFigure 6 As shown, the glass transition temperature of the bioplastic obtained in Example 4 is 22.71 °C; as Figure 7 shown, the tensile deformation of the bioplastic obtained in Example 4 under stress is about 10%, and the tensile strength is about 19 MPa, showing good mechanical properties.

[0071] As Figure 8 shown, the stress-strain curves of the bioplastic obtained through Example 4 after being soaked in water for 1 day and 7 days. After being soaked in water for 1 day, the mechanical properties of the prepared bioplastic only decreased slightly, indicating that the bioplastic has a certain water resistance; after being continuously soaked in water for 7 days, due to the dissociation of the dynamic boron-oxygen bonds contained in the network, the mechanical properties of the bioplastic were significantly reduced. The tensile strength decreased from the initial about 16 MPa to about 9 MPa, while the tensile deformation increased significantly, reaching about 21%. This situation also provides the possibility of natural degradation outdoors.

[0072] Example 5

[0073] A synthesis method of a bioplastic based on a cellulose ether deep eutectic solvent, comprising the following steps:

[0074] Step S1: Weigh 1 g of ethyl cellulose and 3 g of thymol, with a mass ratio of 1:3, stir at 80 °C until clear and transparent, and then take it out and cool it to room temperature to complete the preparation of the cellulose ether deep eutectic solvent;

[0075] Step S2: Add 0.6873 g of isophorone diisocyanate to the cellulose ether deep eutectic solvent prepared in Step S1, and react at room temperature for 2 h;

[0076] Step S3: Add 0.4234 g of 4-aminophenylboronic acid to the mixed solvent prepared in Step S2, and stir at room temperature for 24 h; the mixture obtained in the above step is denoted as solution A;

[0077] Step S4: Prepare the cellulose ether deep eutectic solvent according to the method of Step S1, and then add 6 g of benzyl acrylate and mix evenly; the mixture obtained in the above step is denoted as solution B;

[0078] Step S5: Mix the solution A prepared in Step S3 and the solution B prepared in Step S4 evenly, and let it stand at 80 °C for 8 h to prepare a degradable and recyclable transparent bioplastic.

[0079] As Figure 5 shown, the glass transition temperature of the bioplastic obtained through Example 5 is 22.23 °C;

[0080] As Figure 6As shown, the bioplastic obtained in Example 5 has a tensile deformation of about 8% under stress, a tensile strength of about 22 MPa, and has good mechanical properties.

[0081] As Figure 9 and Figure 10 shown, even after the bioplastic obtained in Example 5 breaks, it can be welded together by hot pressing, and the mechanical strength of the welded sample only decreases slightly, showing good hot pressing repair performance. In addition, the prepared bioplastic can also be made into a transparent packaging bag by heat sealing, showing good thermoplastic processing performance;

[0082] As Figure 12 shown, the bioplastic obtained in Example 5 almost completely disappears after being placed in the outdoor environment for 90 days, showing good degradability.

Claims

1. A method for synthesizing a bioplastic based on a cellulose ether deep eutectic solvent, characterized in that, It includes the following steps: Step S1: Prepare a cellulose ether deep eutectic solvent by mixing a cellulose ether hydrogen bond donor and a hydrophobic phenolic hydrogen bond acceptor in a mass ratio of 1:3 to 1:9 at 60 to 90 °C; Step S2: Add an active intermediate containing an isocyanate group to the cellulose ether deep eutectic solvent obtained in Step S1 and react at room temperature for 1 - 4 h; Step S3: Add a small molecule substance containing a phenylboronic acid group to the mixed solvent obtained in Step S2 and stir at room temperature for 24 - 48 h to obtain a mixture denoted as Solution A; Step S4: Prepare a cellulose ether deep eutectic solvent according to Step S1, add a polymerizable monomer and mix evenly to obtain a mixture denoted as Solution B; wherein, the mass ratio of the polymerizable monomer to the cellulose ether deep eutectic solvent is 0.5:1 to 1.5:1; Step S5: Mix Solution A obtained in Step S3 and Solution B obtained in Step S4 evenly, and let it stand at 60 to 90 °C for 8 - 12 h to obtain a degradable and recyclable transparent bioplastic.

2. The synthesis method of the bioplastic based on the cellulose ether deep eutectic solvent according to claim 1, wherein In Step S1, the cellulose ether hydrogen bond donor is one or more of methyl cellulose, ethyl cellulose, and methyl ethyl cellulose.

3. The synthesis method of the bioplastic based on cellulose ether deep eutectic solvent according to claim 1 or 2, characterized in that, In Step S1, the hydrophobic phenolic hydrogen bond acceptor is one or more of thymol, carvacrol, vanillin, and eugenol.

4. The synthesis method of the bioplastic based on the cellulose ether deep eutectic solvent according to claim 3, characterized in that, In Step S2, the active intermediate containing an isocyanate group is one or more of isophorone diisocyanate, cyclohexane - 1,4 - diisocyanate, 4,4'-methylenebis(phenyl isocyanate), and 4,4 - diisocyanatodicyclohexylmethane.

5. The synthesis method of the bioplastic based on the cellulose ether deep eutectic solvent according to claim 3, wherein In Step S3, the small molecule substance containing a phenylboronic acid group is one or more of 3 - carboxyphenylboronic acid, 4 - carboxyphenylboronic acid, 2 - aminophenylboronic acid, 3 - aminophenylboronic acid, and 4 - aminophenylboronic acid.

6. The synthesis method of the bioplastic based on the cellulose ether deep eutectic solvent according to claim 3, wherein In Step S4, the polymerizable monomer is one or more of 2 - hydroxyethyl acrylate, 2 - hydroxypropyl methacrylate, 2 - phenoxyethyl acrylate, isobornyl acrylate, and benzyl acrylate.

7. A bioplastic based on a cellulose ether deep eutectic solvent, characterized in that, The bioplastic is prepared by the synthesis method described in any one of claims 1 to 6.

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