Biomass-based water-solid plastic as well as preparation method, water-solid forming method and application thereof

Abstract

The invention discloses biomass-based water-solid plastic as well as a preparation method, a water-solid forming method and application thereof, and belongs to the field of plastics, the water-solid plastic is plastic which can be subjected to self-deformation forming only by using water without using a mold, and the obtained shape can be kept stable and is not influenced by water environment and humidity change. The water-solid forming method mainly comprises the following steps: pre-designing the shape of the biomass-based water-solid plastic, performing water treatment, and performing drying treatment after deformation. The water-curable plastic can be automatically deformed into various one-dimensional, two-dimensional or three-dimensional shapes, no mold is needed, expensive and complex instruments and equipment are not needed, and the method is a plastic forming processing method which is simple to operate, low in energy consumption, low in cost, green, environment-friendly and carbon-reducing. The biomass-based water-solid plastic is prepared from biomass which is rich in reserves, low in cost, sustainable to regenerate, biodegradable and good in biocompatibility, has good mechanical properties and can be widely applied to various fields.

Description

Technical Field

[0001] This invention relates to the field of plastics, and in particular to a biomass-based water-solid plastic and its preparation method, water-solid molding method and application. Background Technology

[0002] Plastics, as a key material in modern industrial systems, are widely used in packaging, building materials, electronics, medical devices, and many other fields. However, the environmental problems they cause are becoming increasingly serious. Plastic waste accumulated in the ocean, soil, and atmosphere after disposal leads to microplastic pollution, harming ecosystem balance and human health. Currently, most mainstream plastics are made from petroleum, relying on non-renewable resources and often failing to degrade naturally. Furthermore, traditional plastic molding processes require specialized molds and energy-intensive processing equipment, resulting in high production costs and limiting the flexibility of product form adjustments due to long mold design and replacement cycles.

[0003] To address the aforementioned issues, environmentally friendly biomass-based plastics have become a research hotspot in the scientific research field. Among them, hydroplastics, as an innovative material, offer a new direction for sustainable plastics research and development due to their characteristic of "using only water as a molding medium and being able to be reshaped multiple times." Although existing hydroplastics have achieved green raw materials and environmentally friendly molding processes, their applications still have significant limitations: on the one hand, the molding process is highly dependent on molds and cannot achieve self-deformation without external molds, making it difficult to adapt to complex shape requirements; on the other hand, hydroplastics have a high affinity for water and are prone to unexpected deformation in high humidity environments, and may even lose their original shape stability upon re-contact with water, severely limiting their application in aquatic environments.

[0004] Therefore, there is an urgent need to develop a biodegradable biomass-based water-solid plastic that does not rely on molds, is self-deformable, and can maintain its shape stability in high humidity environments and when it comes into contact with water again. Summary of the Invention

[0005] The purpose of this invention is to provide a biomass-based hydroplastic to solve the problems in the prior art where the molding of hydroplastics depends on molds and the shape of hydroplastics is easily affected by water molecules.

[0006] The present invention also aims to provide a method for preparing biomass-based aqueous solid plastics.

[0007] The present invention also aims to provide a water-based solidification method to solve the technical problems of existing water-based plastic molding, which relies on complex molds, has poor process flexibility, and the molded products are prone to deformation and collapse due to the action of water molecules. The method achieves simultaneous completion of the molding process and shape stabilization through a water-triggered solidification reaction, thereby improving molding efficiency and the environmental resistance of the products.

[0008] Another objective of this invention is to provide applications of the above-mentioned biomass-based hydrosolid plastics and their hydrosolid molded articles.

[0009] In a first aspect, the present invention provides a biomass-based water-solid plastic, wherein the structure of the biomass-based water-solid plastic is a water-responsive differential structure; Water-responsive differential structures include bilayer, multilayer, gradient, regional, and aspect ratio-adjusted structures; The shape of biomass-based water-solid plastics is water-induced self-deformation, and the resulting shape is permanent; The raw materials for biomass-based hydrosolid plastics include one or more of the following: biomass-based polymer materials, biomass-based nanomaterials, and biomass-based natural fiber materials.

[0010] By employing the above technical solutions, biomass-based hydrosolid plastics are constructed using water-responsive differential structures. The asymmetric driving force generated by the differences in water response (water absorption swelling degree, rate, water loss shrinkage characteristics, etc.) across different structural regions enables water-induced self-deformation of the material, allowing shape shaping without external mold constraints. Specifically, the water-responsive differential structures include bilayer, multilayer, gradient, regional structures, and structures with adjustable aspect ratios. Bilayer / multilayer structures are formed by combining material layers with different water-responsive properties; gradient structures are achieved through gradient distribution of components or crosslinking degrees; regional structures are endowed with differentiated water-responsive capabilities through local modification; and aspect ratio adjustment is achieved through precise control of deformation morphology via geometric design. The biomass-based hydrosolid plastics constructed using these strategies exhibit water-induced self-deformation, autonomously transforming their shape upon contact with water. Furthermore, the deformed shape is permanent and will not revert to its initial state due to subsequent changes in environmental humidity or slight contact with water.

[0011] Using biomass-based materials as raw materials offers several advantages. First, it fully leverages the renewable and biodegradable nature of biomass resources, reducing plastics' dependence on non-renewable petroleum resources at the source and minimizing environmental pollution after disposal, aligning with the concept of green and sustainable development. Second, different types of biomass-based materials possess rich structural and performance tunability, allowing for the regulation of water response characteristics, mechanical properties, and morphological stability through component combination and composite manipulation. Biomass-based polymers provide the basic framework and processing performance for plastics, with functional groups such as hydroxyl and carboxyl groups in their molecular structure serving as sites for subsequent cross-linking structures and regulating hydrophilicity and hydrophobicity. Biomass-based nanomaterials, with their high specific surface area and high reactivity, can significantly improve the mechanical strength, thermal stability, and water response sensitivity of materials, while optimizing the water response structure by controlling the dispersion state of nanoparticles. Biomass-based natural fiber materials further enhance the mechanical support properties of materials, improving the durability of finished products. The synergistic effect of various biomass materials achieves a balance of multiple functions, including water-induced self-deformation, morphological stability, mechanical reliability, and biodegradability, overcoming the limitations of existing biomass-based materials with single functions.

[0012] In addition, biomass-based hydroplastics exhibit excellent shape stability, meaning that the shape remains stable for no less than 6 months in the full humidity range of 0% to 100% RH and for no less than 2 months in an aquatic environment, effectively solving the problem that existing hydroplastics are susceptible to water-induced failure.

[0013] Preferably, the biomass-based polymeric materials include one or more of the following: cellulose, hemicellulose, chitin, chitosan, lignin, xylan, starch, gums, natural rubber, alginate, proteins, polyhydroxyalkanoates, polylactic acid, and cyclodextrin.

[0014] Preferably, the biomass-based nanomaterials include one or more of the following: cellulose nanocrystals, cellulose nanofibers, chitin nanocrystals, chitin nanofibers, bacterial cellulose, chitosan nanoparticles, lignin nanoparticles, starch nanocrystals, and starch nanoparticles.

[0015] Preferably, biomass-based natural fiber materials include one or more of plant fibers, animal fibers, and microbial fibers.

[0016] Preferably, the plant fiber includes one or more of cotton, kapok, flax, sisal, leaf fiber, and bamboo fiber.

[0017] Preferably, animal fibers include one or more of hair fibers, spider silk, and silkworm silk.

[0018] Preferably, the microbial fiber includes one or more of mycelia and microalgae fibers.

[0019] Preferably, the shape of the biomass-based hydrosolid plastic is stable, with a shape stability time of not less than 6 months in a humidity of 0% to 100% RH and a shape stability time of not less than 2 months in an aquatic environment.

[0020] Secondly, this invention also discloses a method for preparing biomass-based aqueous solid plastics, comprising the following steps: S1. Biomass-based material 1 is obtained by combining biomass-based polymer materials and / or biomass-based nanomaterials and / or biomass-based natural fiber materials; S2. Biomass-based material 2 is obtained by combining biomass-based polymer materials and / or biomass-based nanomaterials and / or biomass-based natural fiber materials. S3. Combine biomass-based material 1 and biomass-based material 2 to construct a water-responsive differential structure and obtain biomass-based water-solid plastic.

[0021] Preferably, the method for combining biomass-based material 1 and biomass-based material 2 and constructing water-responsive differential structures includes one or more of chemical crosslinking, chemical modification, physical structure, and intermolecular interactions.

[0022] Preferably, chemical crosslinking includes dynamic bond crosslinking and non-dynamic bond crosslinking; dynamic bond crosslinking includes hydrogen bonds, disulfide bonds, ester / amide bonds, imine bonds (Schiff bases), borate ester bonds, etc.; non-dynamic bond crosslinking includes metal coordination bonds, double tellurium bonds, azo bonds, ether bonds, diarylethylene bonds, or cyclopentadienone bonds.

[0023] Preferably, when the method of combining biomass-based material 1 and biomass-based material 2 is specifically metal coordination bond, the biomass-based aqueous solid plastic is composed of a biomass layer and a biomass metal ion layer. Inorganic acid solution or organic acid solution can be coated between the biomass layer and the biomass metal ion layer for bonding between the two layers.

[0024] Preferably, the chemical modifications include hydrophilic modifications and hydrophobic modifications; hydrophilic modifications include groups such as hydroxyl, carboxyl, amino, sulfonic acid, amide, and phosphate groups, as well as polymeric segments such as polyvinyl alcohol, polyethylene glycol, and polyacrylic acid; hydrophobic modifications include alkyl chains such as methyl, ethyl, and long-chain alkyl, aromatic groups such as benzene rings, naphthyl, and polycyclic aromatic hydrocarbon derivatives, and carbon-fluorine-containing compounds such as perfluoroalkyl segments and polytetrafluoroethylene segments.

[0025] Preferably, the physical structure includes one or more of the following: good solvent effect, porosity, crystallinity, molecular chain orientation, and surface / interface properties; Preferably, the intermolecular interactions include one or more of the following: hydrogen bonds, electrostatic interactions, hydrophobic interactions, van der Waals forces, and ionic dipole interactions.

[0026] Thirdly, the present invention also discloses a water-solid molding method, comprising the following steps: A1. Pre-design of the shape of water-based solid plastics; A2. Water treatment for water-solid plastics; A3. Drying treatment of water-solid plastics after deformation.

[0027] Preferably, the pre-design of the shape of the water-based plastic includes, for example, aspect ratio design. The shape is shaped by adjusting the aspect ratio. For example, when the width is 0.75cm and the aspect ratio is in the range of 1:1, 1:2, 1:3, 1:4, 1:5, or 1:6, the shape can be shaped into a semi-circular tube, a 4 / 5 circular tube, a spiral, a 1.7-turn ring, a 2.2-turn ring, or two spirals. Preferably, water treatment can be accomplished by immersion in water, application of water, spraying, or balancing in a humid environment.

[0028] Preferably, the drying method includes one or more of the following: natural drying, forced air drying, vacuum drying, freeze drying, microwave drying, equilibrium drying in a low humidity environment, or desiccant drying.

[0029] Preferably, biomass-based hydrosolidic plastics are available in the form of films, sheets, foams, fibers, flakes, tubular forms, or three-dimensional forms printed in three dimensions.

[0030] Fourthly, the present invention also provides an application of biomass-based aqueous solid plastics, including but not limited to the fields of smart materials and devices, including but not limited to soft robots, biosensors, triboelectric nanogenerators, supercapacitors / batteries, electronic device substrates, etc.; the fields of biomedical materials, including but not limited to medical molding materials, wound dressings, tissue engineering scaffolds, human electronic skin, surgical suture fixation, drug delivery, etc.; and the fields of industry and packaging, including but not limited to smart packaging, automotive interiors, consumer product packaging, water treatment and adsorption materials, etc.

[0031] The beneficial effects of this invention are: 1. Traditional plastic molding often relies on expensive specialized equipment and requires customized molds for different products, which not only increases production costs but also limits production flexibility. Existing processes generally require stringent reaction conditions such as high temperature, high pressure, and oxygen-free curing, which consume a large amount of energy and produce pollutants, contradicting the concept of green development. This invention, through an innovative technological approach, completely eliminates the dependence on the aforementioned high-cost equipment, specialized molds, and stringent reaction conditions, achieving a dual breakthrough in cost reduction and efficiency improvement, as well as energy conservation and emission reduction, from the source of production.

[0032] 2. This invention uses green and sustainable biomass materials as the core raw material for the production of water-based plastics. The raw materials are derived from nature and are recyclable, avoiding dependence on non-renewable petroleum resources. The water-based plastics made from these raw materials can be completely decomposed in the natural environment through biodegradation after disposal, leaving no residue and causing no pollution. This completely solves the environmental problems caused by the difficulty in degrading petroleum-based plastics and the soil and marine pollution caused by long-term accumulation, providing a practical and feasible technical solution for solving "white pollution".

[0033] 3. The aqueous solid plastic of this invention has excellent shape preprogrammability, enabling flexible shape pre-design according to actual needs to achieve diverse product shapes; at the same time, it can maintain shape stability and structural and performance integrity even under high humidity environments and long-term immersion in water. Its biodegradable properties can significantly reduce the environmental burden of the product, giving this biomass-based aqueous solid plastic multiple core advantages such as low cost, high efficiency, green and environmentally friendly production process.

[0034] 4. The water-based plastics of this invention have shown great market potential and important research value in multiple fields, including but not limited to soft robots, biosensors, triboelectric nanogenerators, supercapacitors / batteries, and electronic device substrates in the field of smart materials and devices; medical molding materials, wound dressings, tissue engineering scaffolds, human electronic skin, surgical suture fixation, and drug delivery in the field of biomedicine; and smart packaging, automotive interiors, consumer product packaging, and water treatment and adsorption materials in the industrial and packaging fields. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the biomass-based water-solid plastic of Embodiment 1 of the present invention, where a is a schematic diagram of the preparation process and b is a schematic diagram of the deformation and shape stability after being cut and placed in water. Figure 2 The deformation process of the biomass-based water-solid plastic of Example 1 of the present invention, cut to a fixed width of 0.75cm and with length-to-width ratios of 1:1, 1:2, 1:3, 1:4, 1:5, and 1:6, after being placed in water, is shown, as well as the shape stability after natural drying and re-absorbing water. Figure 3 The biomass-based hydrosolid plastic of Embodiment 1 of the present invention is based on Figure 2 The film was cut according to a simple aspect ratio deformation law. After being placed in water, the cut film exhibited a variety of shapes, and its shape stability in both natural and aquatic environments was demonstrated after complete deformation.

[0036] Figure 4The biomass-based aqueous solid plastic film of Example 1 of this invention was cut into films with a width of 0.75 cm and an aspect ratio of 1:7, and then immersed in water to completely form a spiral before being naturally dried to obtain the biomass-based aqueous solid plastic. The shape stability of this plastic was demonstrated when placed in different humidity environments, such as 23%RH, 43%RH, 65%RH, 75%RH, and 99%RH. Figure 5 The biomass-based water-based solid plastic film of Example 1 of this invention was cut into rectangles with a width of 0.75 cm and length-to-width ratios of 1:1, 1:2, 1:4, and 1:6. After being soaked in water, the films were shaped into semi-circular tubular shapes, 4 / 5 circular tubular shapes, 1.7-turn circular shapes, and 2 spirals. The shape stability of the four types of films that had been fully deformed was demonstrated by soaking them in water for another 60 days.

[0037] Figure 6 The water-based solid plastic D / CS-CNC-Cu of Example 1 of this invention 2+ Thin films and other biomass-based thin films (such as CS thin films, CS-CNC thin films, CS-CNC-Cu thin films) 2+ Comparison of stress-strain curves of thin films.

[0038] Figure 7 The biomass-based hydrosolidic plastic D / CS-CNC-Cu of Example 1 of this invention 2+ Thin films and other biomass-based thin films (such as CS thin films, CS-CNC thin films, CS-CNC-Cu thin films) 2+ A comparison of Young's modulus and fracture energy of thin films; Figure 8 The biomass-based hydrosolidic plastic D / CS-CNC-Cu of Example 1 of this invention 2+ Scanning electron microscope image of the thin film surface, where a is D / CS-CNC-Cu 2+ Scanning electron microscope image of the CS-CNC layer of the thin film, b is D / CS-CNC-Cu 2 + CS-CNC-Cu thin film 2+ SEM image.

[0039] Figure 9 The biomass-based hydrosolidic plastic D / CS-CNC-Cu of Example 1 of this invention 2+ Scanning electron microscope image of the cross-section of the thin film, where a is D / CS-CNC-Cu. 2+ The cross-sectional morphology of the thin film in the dry state is shown in Figure b, which shows the cross-sectional morphology of the CS-CNC layer after absorbing water for 15 min, and Figure c shows the CS-CNC-Cu layer. 2+ The cross-sectional morphology of the layer after 15 minutes of water absorption is shown.

[0040] Figure 10 CS-CNC-Cu, a biomass-based hydrosolid plastic of Example 1 of this invention. 2+ A schematic diagram of the C, O, and Cu element distribution on the surface of the layer; Figure 11 This is a thermal stability test diagram of the biomass-based aqueous solid plastic of Example 1 of the present invention; Figure 12 The natural degradation of the biomass-based hydrosolid plastic of Example 1 of the present invention is compared with that of Paper, PE, and PLA. Figure 13 This is a schematic diagram of the degradation rate of the biomass-based hydrosolid plastic of Example 1 of the present invention, and a comparison with the degradation rates of Paper, PE, and PLA. Detailed Implementation

[0041] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below.

[0042] A biomass-based water-solid plastic, wherein the structure of the biomass-based water-solid plastic is a water-responsive differential structure; Water-responsive differential structures include bilayer, multilayer, gradient, regional, and aspect ratio-adjusted structures; The shape of biomass-based water-solid plastics is water-induced self-deformation, and the deformed shape is permanent; The raw materials for biomass-based hydrosolid plastics include one or more of the following: biomass-based polymer materials, biomass-based nanomaterials, and biomass-based natural fiber materials.

[0043] By employing the above technical solutions, biomass-based hydrosolid plastics are constructed using water-responsive differential structures. The asymmetric driving force generated by the differences in water response (degree and rate of water absorption and expansion, shrinkage characteristics upon water loss, etc.) across different structural regions enables water-induced self-deformation of the material, achieving morphological shaping without external mold constraints. Specifically, the water-responsive differential structures include bilayer, multilayer, gradient, regional structures, and structures with adjustable aspect ratios. Bilayer / multilayer structures are formed by combining material layers with different water-responsive properties; gradient structures are achieved through gradient distribution of components or crosslinking degrees; regional structures are endowed with differentiated water-responsive capabilities through local modification; and aspect ratio adjustment is achieved through precise control of the deformed morphology via geometric design. The biomass-based hydrosolid plastics constructed using these strategies exhibit water-induced self-deformation, autonomously transforming their shape upon contact with water. Furthermore, the deformed shape is permanent and will not revert to its initial state due to subsequent changes in environmental humidity or slight contact with water.

[0044] Using biomass-based materials as raw materials offers several advantages. First, it fully leverages the renewable and biodegradable nature of biomass resources, reducing plastics' dependence on non-renewable petroleum resources at the source and minimizing environmental pollution after disposal, aligning with the concept of green and sustainable development. Second, different types of biomass-based materials possess rich structural and performance tunability, allowing for the regulation of water response characteristics, mechanical properties, and morphological stability through component combination and composite manipulation. Biomass-based polymers provide the basic framework and processing performance for plastics, with functional groups such as hydroxyl and carboxyl groups in their molecular structure serving as sites for subsequent cross-linking structures and regulating hydrophilicity and hydrophobicity. Biomass-based nanomaterials, with their high specific surface area and high reactivity, can significantly improve the mechanical strength, thermal stability, and water response sensitivity of materials, while optimizing the water response structure by controlling the dispersion state of nanoparticles. Biomass-based natural fiber materials further enhance the mechanical support properties of materials, improving the durability of finished products. The synergistic effect of various biomass materials achieves a balance of multiple functions, including water-induced self-deformation, morphological stability, mechanical reliability, and biodegradability, overcoming the limitations of existing biomass-based materials with single functions.

[0045] In addition, biomass-based hydroplastics exhibit excellent shape stability, meaning that the shape remains stable for no less than 6 months in the full humidity range of 0% to 100%, and for no less than 2 months in an aquatic environment, effectively solving the problem that the shape of existing hydroplastics is easily affected by water and fails.

[0046] In some embodiments, biomass-based polymeric materials include one or more of cellulose, hemicellulose, chitin, chitosan, lignin, xylan, starch, gums, natural rubber, alginate, proteins, polyhydroxyalkanoates, polylactic acid, and cyclodextrin; biomass-based nanomaterials include one or more of cellulose nanocrystals, cellulose nanofibers, chitin nanocrystals, chitin nanofibers, bacterial cellulose, chitosan nanoparticles, nanolignin particles, starch nanocrystals, and starch nanoparticles; biomass-based natural fiber materials include one or more of plant fibers, animal fibers, and microbial fibers; plant fibers include one or more of cotton, kapok, flax, sisal, leaf fibers, and bamboo fibers; animal fibers include one or more of hair fibers, spider silk, and silk; and microbial fibers include one or more of hyphae and microalgae fibers.

[0047] A method for preparing a biomass-based aqueous solid plastic includes the following steps: S1. Biomass-based material 1 is obtained by combining biomass-based polymer materials and / or biomass-based nanomaterials and / or biomass-based natural fiber materials; S2. Biomass-based material 2 is obtained by combining biomass-based polymer materials and / or biomass-based nanomaterials and / or biomass-based natural fiber materials. S3. Combine biomass-based material 1 and biomass-based material 2 to construct a water-responsive differential structure and obtain biomass-based water-solid plastic.

[0048] By employing the above technical solution, steps S1 and S2 respectively prepare two biomass-based materials with differentiated water-responsive characteristics. By controlling the composition, ratio, and compounding method of the two materials, significant differences are achieved between Material 1 and Material 2 in terms of water absorption swelling rate, swelling rate, and water loss shrinkage characteristics, laying the foundation for subsequent construction of water-responsive differential structures. Step S3 combines the two materials through a specific bonding method, forming a tightly integrated structure. When this structure comes into contact with water, the difference in water response between Material 1 and Material 2 generates asymmetric stress, thereby driving the material to undergo self-deformation. This preparation method is simple, highly controllable, and requires no complex equipment or stringent reaction conditions. The type of water-responsive differential structure (such as bilayer, gradient, etc.) can be flexibly designed by controlling the material composition and bonding method, achieving precise control over the material's shape.

[0049] In some embodiments, the method of combining biomass-based material 1 and biomass-based material 2 includes one or more of chemical crosslinking, chemical modification, physical structure, and intermolecular interactions to construct a water-responsive differential structure. Employing multiple combination methods allows for flexible control of the bonding strength and interfacial interactions between material 1 and material 2, while precisely constructing a water-responsive differential structure. Specifically, chemical crosslinking can form a stable crosslinking network at the interface of the two materials by forming covalent or non-covalent bonds (dynamic / non-dynamic bonds), which not only enhances interfacial bonding but also further amplifies the water-responsive difference between the two materials by controlling the difference in crosslinking degree. Chemical modification can directly endow the two materials with differentiated water affinity by modifying the surface of material 1 or material 2 with hydrophilic / hydrophobic properties, simplifying the construction process of the water-responsive differential structure. Physical structure control (such as good solvent action, pore design, etc.) can change the microstructure of the materials (such as porosity, crystallinity), thereby affecting the water absorption performance and water diffusion rate of the materials, forming a physical-level water-responsive difference. Intermolecular interactions (such as hydrogen bonds, electrostatic interactions, etc.) can achieve self-assembly of the two materials without the need for additional crosslinking agents, simplifying the process while ensuring the stability of the interfacial bonding.

[0050] In some embodiments, chemical crosslinking includes dynamic and non-dynamic crosslinking. Dynamic crosslinking includes hydrogen bonds, disulfide bonds, ester / amide bonds, imine bonds (Schiff bases), borate ester bonds, etc.; non-dynamic crosslinking includes metal coordination bonds, double tellurium bonds, azo bonds, ether bonds, diarylethylene bonds, or cyclopentadienone bonds. Dynamic crosslinking is reversible, allowing bond breakage and recombination during water treatment, providing a certain degree of flexibility for material deformation. Simultaneously, it reforms a stable bonded structure after drying, ensuring the permanence of the deformed shape. Non-dynamic crosslinking, on the other hand, forms a stable rigid crosslinking network, significantly improving the mechanical strength and morphological stability of the material, making it particularly suitable for applications requiring high structural strength. For example, metal coordination bonds (such as those formed by copper ions and the amino and hydroxyl groups of chitosan) not only enhance interfacial bonding strength but also regulate the hydrophilicity and crystallinity of the material, further optimizing water response differences. Hydrogen bonds, as a type of dynamic bond, can respond rapidly to the action of water molecules, improving the material's deformation sensitivity. The combination of different types of crosslinks can balance the deformation capacity and stability of materials, meeting the needs of different application scenarios.

[0051] In some embodiments, when the method of bonding biomass-based material 1 and biomass-based material 2 is specifically metal coordination bonding, the biomass-based hydrosolid plastic consists of a biomass layer and a biomass metal ion layer. An inorganic acid solution or an organic acid solution can be coated between the biomass layer and the biomass metal ion layer as a crosslinking solution. When the bonding method is limited to metal coordination bonding, the resulting "biomass layer-biomass metal ion layer" bilayer structure exhibits a clear and stable difference in water response. In the biomass metal ion layer, metal ions form stable coordination bonds with the functional groups of the biomass material, reducing the material's hydrophilicity and decreasing the degree of water absorption and swelling. Meanwhile, the biomass layer, without the introduction of metal ions, maintains high hydrophilicity and is prone to significant swelling after water absorption. This significant difference in water response can generate strong driving stress, enhancing the material's self-deformation ability and deformation rate. Coating the two layers with an inorganic or organic acid solution as a crosslinking solution can further enhance the interfacial bonding strength: the acid solution can promote the protonation of the functional groups of biomass materials, improve the coordination reaction efficiency with metal ions, and at the same time, the acid molecules can act as bridges to form additional hydrogen bonds or covalent bonds, preventing the two layers from peeling off during deformation and ensuring the integrity of the material structure and its service life.

[0052] In some embodiments, chemical modification includes hydrophilic modification and hydrophobic modification. Hydrophilic modification includes groups such as hydroxyl, carboxyl, amino, sulfonic acid, amide, and phosphate groups, as well as polymeric segments such as polyvinyl alcohol, polyethylene glycol, and polyacrylic acid. Hydrophobic modification includes alkyl chains such as methyl, ethyl, and long-chain alkyl groups, aromatic groups such as benzene rings, naphthyl groups, and polycyclic aromatic hydrocarbon derivatives, and fluorocarbon-containing compounds such as perfluoroalkyl segments and polytetrafluoroethylene segments. Chemical modification can directly regulate the difference in hydrophilicity and hydrophobicity between material 1 and material 2, thereby constructing a precise water-responsive differential structure. Hydrophilic modification enhances the water absorption capacity and water absorption rate of the material by introducing hydrophilic groups or hydrophilic segments; hydrophobic modification reduces the hydrophilicity of the material and reduces the degree of water absorption and swelling by introducing hydrophobic groups or hydrophobic segments. For example, by modifying material 1 with hydrophilic properties (e.g., introducing hydroxyl groups) and material 2 with hydrophobic properties (e.g., introducing long-chain alkyl groups), the resulting composite structure exhibits rapid and substantial water absorption and expansion in material 1 upon contact with water, while material 2 shows only slight expansion. This generates strong asymmetric stress-driven self-deformation. The selection of different types of modifying groups / segments allows for flexible control of the difference in hydrophilicity and hydrophobicity, thereby regulating the degree and rate of deformation to meet various shape design requirements. Furthermore, the chemically modified groups can participate in subsequent cross-linking reactions, further enhancing the structural stability of the material.

[0053] In some embodiments, the physical structure includes one or more of the following: good solvent effect, porosity, crystallinity, molecular chain orientation, and surface / interface properties. Physical structure regulation can optimize the water response characteristics of materials at the microscopic level, creating differences in water response at the physical level. Good solvent effect can regulate the dissolution and dispersion state of biomass materials, affecting the density of the material and thus the water absorption rate (dense materials absorb water slowly, while porous materials absorb water quickly). Porosity design, by regulating the porosity and pore size of the material, changes the diffusion path and rate of water molecules; high-porosity materials absorb water quickly and have a high expansion rate, while low-porosity materials have the opposite. Crystallinity regulation changes the proportion of crystalline regions in the material; crystalline regions have tightly packed molecular chains and weak water absorption capacity, while amorphous regions have loose molecular chains and strong water absorption capacity. Differences in water response can be achieved by regulating the difference in crystallinity between material 1 and material 2. Molecular chain orientation regulation can give the material different water absorption and expansion characteristics in specific directions, further enriching the diversity of deformation. Surface / interface property regulation (such as roughness and surface energy) can affect the contact angle between the material and water, thus affecting the initial water absorption rate. Physical structure regulation does not require the introduction of additional chemical reagents, the process is green and environmentally friendly, and it can work synergistically with chemical crosslinking and chemical modification to further improve the accuracy and stability of water-responsive differential structures.

[0054] In some embodiments, intermolecular interactions include one or more of hydrogen bonds, electrostatic interactions, hydrophobic interactions, van der Waals forces, and ionic dipole interactions. Intermolecular interactions enable the tight bonding between material 1 and material 2, while simultaneously regulating the material's water-response properties. Hydrogen bonds can form between the functional groups of the two materials (e.g., the hydroxyl group of material 1 and the amino group of material 2), enhancing interfacial bonding. Simultaneously, the formation and breaking of hydrogen bonds can respond to water molecule interactions, improving the material's deformation flexibility. Electrostatic interactions can occur between materials with opposite charges (e.g., modified positively charged material 1 and negatively charged material 2), enabling their self-assembly and recombination. Simultaneously, electrostatic interactions can influence the diffusion and adsorption of water molecules within the material, regulating water absorption performance. Hydrophobic interactions can cause hydrophobic groups in the material to aggregate, forming hydrophobic regions, reducing the material's hydrophilicity, and creating a difference in water response compared to hydrophilic regions. Van der Waals forces and ionic dipole interactions can further enhance the stability of the interfacial bonding, ensuring that the material does not undergo interfacial separation during deformation. The synergy of multiple intermolecular interactions allows for precise regulation of water response differences while maintaining material structural stability, thereby improving the material's deformation performance and morphological stability.

[0055] In some embodiments, a biomass-based hydrosolid plastic is obtained by drying after constructing a water-responsive differential structure.

[0056] A water-based solidification method includes the following steps: A1. Pre-design of the shape of water-based solid plastics; A2. Water treatment for water-solid plastics; A3. Drying treatment of water-solid plastics after deformation.

[0057] By adopting the above technical solutions, the A1 step shape pre-design can accurately design the initial morphology (such as size, aspect ratio, and cutting shape) of biomass-based hydrosolid plastics according to actual application requirements. It does not rely on complex molds and can be completed by simple cutting, which significantly improves the flexibility and efficiency of the molding process. The A2 step water treatment, as a deformation triggering step, activates the material's water response difference through the action of water, driving the material to self-deform according to the pre-designed rules. It does not require external force or mold constraints, realizing moldless self-forming. The A3 step drying treatment after deformation can solidify the deformed shape, so that a stable intermolecular interaction and cross-linking network are formed inside the material, realizing "simultaneous completion of molding and stabilization", which significantly improves molding efficiency. At the same time, the dried product has excellent morphological stability and can withstand high humidity and water environments.

[0058] In some embodiments, the shape pre-design of the water-based plastic can include, for example, aspect ratio design. The shape can be changed according to the designed aspect ratio. When the width is 0.75cm and the aspect ratio is in the range of 1:1, 1:2, 1:3, 1:4, 1:5, or 1:6, shapes such as semi-circular tubular, 4 / 5 circular tubular, spiral, 1.7-turn ring, 2.2-turn ring, and two spirals can be achieved. By adopting the above technical solutions, the correspondence between the key pre-design parameter of aspect ratio and the deformable shape is clarified, achieving precise and controllable shape. At different widths, changes in the aspect ratio can regulate the distribution and magnitude of asymmetric stress within the material, thereby forming different shapes (semi-circular ring, ring, spiral, tubular, etc.). For example, when the width is 0.5cm, as the aspect ratio increases, the shape transformation of the material gradually diversifies, transitioning from a semi-circular ring to multiple-turn rings; when the width is 1cm, a tubular structure can be formed at larger aspect ratios (1:5, 1:6). This precise correspondence makes shape pre-design more instructive, eliminating the need for complex structural designs. Diverse target shapes can be obtained simply by adjusting the aspect ratio, significantly reducing molding difficulty and processing costs.

[0059] In some embodiments, water treatment can be accomplished by immersion in water, application of moisture, spraying, or balancing in a humid environment.

[0060] In some embodiments, the drying method includes one or more of the following: natural drying, forced air drying, vacuum drying, freeze drying, microwave drying, equilibrium drying in a low humidity environment, or desiccant drying.

[0061] In some embodiments, the form of biomass-based hydrosolidic plastics includes film, sheet, foam, fiber, flake, tubular, or three-dimensionally printed forms.

[0062] The specific embodiments of the present invention will be described in detail below, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0063] Preparation example: Preparation Example 1: A type of CNC (cellulose nanocrystals) was prepared by the following method: Microcrystalline cellulose was dispersed at 10% w / v in a 63.5% (w / w) sulfuric acid solution and stirred at 45°C and 350 rpm for 2 h. The resulting dispersion was washed with distilled water and centrifuged at 6000 rpm for 15 min at 25°C. This centrifugation was repeated three times until the supernatant became turbid or the pH reached 4. The dispersion was then dialyzed at 4°C for 2 days using a 14 kDa retention membrane. The dialyzed dispersion was sonicated in an ice bath for 10 min to obtain a CNC dispersion.

[0064] Preparation Example 2: A CHN (chitin nanocrystal) was prepared by the following method: Weigh 2.0 g of dried chitin powder and add it to 100 mL of pre-cooled 3M hydrochloric acid solution. Stir continuously at 400 rpm for 90 min at 90 °C using a magnetic stirrer. After the reaction is complete, transfer the flask to an ice-water bath and rapidly cool to room temperature. Centrifuge the cooled liquid at 10,000 rpm for 10 min, repeating the centrifugation three times and discarding the supernatant. Then dialyze the solution using a 14 kDa cutoff membrane at 4 °C for 3 days until the pH is neutral. Finally, sonicate the solution in an ice-water bath for 3 min to obtain a chitin nanocrystal dispersion.

[0065] Example

[0066] Example 1: A biomass-based water-solid plastic was prepared by the following method: S1. Preparation of CS-CNC-Cu 2+ film Take 1 mL of the 10 mg / mL CNC dispersion prepared in Preparation Example 1, 0.53 g of chitosan (CS) with a degree of deacetylation of 75%, and 0.17 g of CuCl2 metal salt, mix them thoroughly with 20 mL of water, add 0.325 mL of 98% acetic acid solution, stir at 600 rpm for 12 h, and after complete dissolution, sonicate for 1 h to remove air bubbles to obtain CS-CNC-Cu 2+ The solution was poured into a 90mm diameter petri dish containing 20mL of CS-CNC-Cu. 2+ The solution was dried at 80℃ for 2.5 h to obtain CS-CNC-Cu. 2+ film.

[0067] S2, Preparation of D / CS-CNC-Cu 2+ film

[0068] Take 1.5 mL of the 10 mg / mL CNC dispersion prepared in Preparation Example 1, mix it with 0.8 g of chitosan with a degree of deacetylation of 75% and 30 mL of water, add 0.42 mL of 98% acetic acid solution, stir at 100 rpm for 12 h until completely dissolved, and sonicate for 1 h to remove bubbles to obtain the CS-CNC solution. The CS-CNC-Cu obtained in S1... 2+ 1 mL of 4 wt% acetic acid solution was coated onto the film, and then 30 mL of CS-CNC solution was cast onto the CS-CNC-Cu film. 2+ The film was dried at 85°C for 6 hours to obtain D / CS-CNC-Cu. 2+ film.

[0069] Figure 8 Display D / CS-CNC-Cu 2+ Scanning electron microscope images of the upper and lower thin film surfaces show that the surfaces are smooth and dense. Figure 9The cross-sectional scanning electron microscope images further revealed the internal structure of the film, and the effects of absorbing water for 15 minutes on both the CS-CNC layer and the CS-CNC-Cu layer. 2+ Pores began to appear in all layers, but the porosity of the CS-CNC layer was relatively lower than that of the CS-CNC-Cu layer. 2+ The layers are denser and the pores are larger. Figure 10 Elemental analysis proved that the elements on the prepared film surface were uniformly distributed. Figure 11 Thermogravimetric analysis results show that D / CS-CNC-Cu 2+ The film reaches its maximum thermal decomposition rate at 230℃, indicating that the material has good thermal stability.

[0070] Example 2: A biomass-based aqueous solid plastic was prepared by the following method: S1. Preparation of CS-CHN-Ca 2+ film, Take 1 mL of the 30 mg / mL CHN dispersion prepared in Preparation Example 2, 0.53 g of chitosan with a degree of deacetylation of 75%, and 0.2 g of CaCl2, and mix them thoroughly with 20 mL of water. Add 0.325 mL of 98% acetic acid solution, stir at 600 rpm for 12 h, and after complete dissolution, sonicate for 1 h to remove air bubbles to obtain CS-CNC-Ca 2+ Solution. Pour 20 mL of CS-CNC-Ca into a 90 mm diameter petri dish. 2+ The solution was dried at 80℃ for 2.5 h to obtain CS-CNC-Ca. 2+ film.

[0071] S2, Preparation of D / CS-CHN-Ca 2+ film

[0072] Take 1.5 mL of the 10 mg / mL CHN dispersion prepared in Preparation Example 2, and mix it with 0.8 g of chitosan with a degree of deacetylation of 75% and 30 mL of water until homogeneous. Then add 0.48 mL of 98% acetic acid solution, stir at 100 rpm for 12 h until completely dissolved, and then sonicate for 1 h to remove bubbles to obtain the CS-CHN solution. The CS-CHN-Ca obtained in S1... 2+ 1 mL of 4 wt% acetic acid solution was coated onto the film, and then 30 mL of CS-CHN solution was poured onto the CS-CHN-Ca film. 2+ The film was dried at 85°C for 6 hours to obtain D / CS-CHN-Ca. 2+ film.

[0073] Example 3: A biomass-based aqueous solid plastic was prepared by the following method: S1. Preparation of CS-CNC-Fe 3+ film Take 1 mL of the 10 mg / mL CNC dispersion prepared in Preparation Example 1, 0.53 g of chitosan with a degree of deacetylation of 75%, and 0.17 g of FeCl3 metal salt, mix them thoroughly with 20 mL of water, add 0.325 mL of 98% acetic acid solution, stir at 600 rpm for 12 h, and after complete dissolution, sonicate for 1 h to remove air bubbles to obtain CS-CNC-Fe 3+ Solution. Pour 20 mL of CS-CNC-Fe into a 90 mm diameter petri dish. 3+ The solution was dried at 80℃ for 2.5 h to obtain CS-CNC-Fe. 3+ film.

[0074] S2, Preparation of D / CS-CNC-Fe 3+ film

[0075] Take 1.5 mL of the 10 mg / mL CNC dispersion prepared in Preparation Example 1, mix it with 0.8 g of chitosan with a degree of deacetylation of 75% and 30 mL of water, add 0.42 mL of 98% acetic acid solution, stir at 100 rpm for 12 h until completely dissolved, and sonicate for 1 h to remove bubbles to obtain the CS-CNC solution. The CS-CNC-Fe obtained in S1... 3+ 1 mL of 4 wt% acetic acid solution was coated onto the film, and then 30 mL of CS-CNC solution was cast onto the CS-CNC-Fe film. 3+ The film was dried at 85°C for 6 hours to obtain D / CS-CNC-Fe. 3+ film.

[0076] Example 4: A biomass-based aqueous solid plastic was prepared by the following method: S1. Preparation of CS-CNC-PVA (polyvinyl alcohol) film 0.25 g of chitosan with a 75% degree of deacetylation was mixed with 10 mL of water and stirred at 600 rpm for 3 h to obtain a CS solution. 0.25 g of polyvinyl alcohol and 10 mL of water were stirred at 95 °C and 600 rpm for 6 h to obtain a PVA solution. The CS solution, PVA solution, and 1 mL of the 10 mg / mL CNC dispersion prepared in Preparation Example 1 were mixed together and stirred at 600 rpm for 3 h to obtain a CS-CNC-PVA dispersion. 20 mL of the CS-CNC-PVA dispersion was poured into a 90 mm diameter petri dish and dried at 80 °C for 2.5 h to obtain a CS-CNC-PVA film.

[0077] S2. Preparation of D / CS-CH3-CNC-PVA thin film

[0078] Take 0.8 g of chitosan with a degree of deacetylation of 75% and mix it with 30 mL of water. Then add 0.42 mL of 98% acetic acid solution and stir at 100 rpm for 12 h until completely dissolved to obtain a CS solution. Take 2 mL of 37% formaldehyde aqueous solution and add it dropwise to the CS solution. Stir at 300 rpm for 6 h. Weigh 0.8 g of sodium cyanoborohydride and dissolve it in 10 mL of ice water. Then add the sodium cyanoborohydride dropwise to the CS solution containing formaldehyde and stir at 300 rpm for 24 h at room temperature to obtain a CS-CH3 solution. Take 1.5 mL of the 10 mg / mL CNC dispersion prepared in Preparation Example 1 and mix it with the CS-CH3 solution to obtain a CS-CH3-CNC dispersion. Cast the CS-CH3-CNC dispersion onto a CS-CNC-PVA film and dry it at 80 °C for 2.5 h to obtain a D / CS-CH3-CNC-PVA film.

[0079] Example 5, water-based molding, will be illustrated by the following example: like Figure 1 As shown, D / CS-CNC-Cu 2+ The film is cut into strips, controlling the aspect ratio, and first soaked in water for 60 minutes, then air-dried for about 240 minutes to obtain a shaped film. Subsequently, this spiral-shaped D / CS-CNC-Cu... 2+ The thin film was placed in a natural environment, and its shape changes were observed and recorded. For example... Figure 1 As shown, the spiral-shaped D / CS-CNC-Cu 2+ Even after prolonged exposure to natural conditions, the thin film maintains its stable helical shape without change. This indicates that the D / CS-CNC-Cu... 2+ The film automatically deforms after being immersed in water and maintains its shape stably. After the film is completely dry, it is re-immersed in water, and the shape is observed to see if it changes. The results show that D / CS-CNC-Cu... 2+ The film can automatically deform after being immersed in water and maintain its shape. After the film is completely dry, we re-immerse the sample in water to verify its morphological stability. Figure 2The results show that in the 0.75cm wide strip samples, a length-to-width ratio of 1:1 (0.75×0.75cm) forms a semi-circular ring; a length-to-width ratio of 1:2 (0.75×1.5cm) forms a single-loop ring; a length-to-width ratio of 1:3 (0.75×2.25cm) forms a spiral; a length-to-width ratio of 1:4 (0.75×3cm) forms a multi-loop ring; a length-to-width ratio of 1:5 (0.75×3.75cm) forms a multi-loop ring; and a length-to-width ratio of 1:6 (0.75×4.5cm) forms a spiral. This demonstrates that the length-to-width ratio of the cut strip is a crucial parameter determining the deformation morphology. The biomass-based hydrosolid plastic undergoes deformation in water within 1 hour and requires only 4 hours for natural drying. After natural drying, it can stably maintain its shape when re-immersed in water.

[0080] (2) Combination cutting of different shapes and display of humidity stability

[0081] D / CS-CNC-Cu 2+ The film was cut into different shapes, and after controlling the aspect ratio of the cut, it was first soaked in water for 60 minutes. It was observed that the film completely deformed and stably maintained its shape within 1 hour, and the shape became more complex. Then, it was naturally air-dried for about 240 minutes to obtain a shaped film. The shape stability after natural drying was no less than 6 months. Even after natural drying, it could still stably maintain its shape when put back into water, and the shape stability was no less than 2 months. Subsequently, various shapes of D / CS-CNC-Cu were... 2+ The thin film was dried in a natural environment, and its shape changes were observed and recorded. The experimental results are as follows: Figure 3 As shown, the composition of different deformations corresponds to the aspect ratio of the film cutting, and respectively exhibits various shapes such as semi-bending, bending, and spiral. Figure 4 The stability of the shape was demonstrated under different humidity levels, and the shape remained stable even at 99% RH for no less than 6 months. Figure 5 The film retains its shape even after being immersed in water for up to two months.

[0082] The above experiments show that the water-solid forming method is effective for D / CS-CNC-Cu. 2+ Films can be transformed into various shapes without the aid of molds and remain stable in high humidity and water environments. They can be applied to a variety of scenarios, reducing molding costs and extending the service life of plastics.

[0083] Performance testing: 1. Mechanical properties For ①CS thin film, ②CS-CNC thin film, ③CS-CNC-Cu 2+ Thin film, ④D / CS-CNC-Cu 2+Mechanical property testing of the thin film was conducted by subjecting the film sample to uniaxial tensile testing. The clamping distance was 10 mm, and the tensile rate was 5 mm / min until the film fractured. The results were as follows: Figure 6 The stress-strain curves shown indicate that D / CS-CNC-Cu 2+ Thin films possess excellent mechanical properties. Figure 7 Displaying D / CS-CNC-Cu 2+ The Young's modulus of the thin film is 4002 MPa, CS-CNC-Cu 2+ The Young's modulus of the film is as high as 4283 MPa, while that of the CS-CNC film is 1752 MPa. The Young's modulus of the CS film can also reach 696 MPa.

[0084] 2. Thermal stability and surface elements

[0085] Figure 8 9 respectively for D / CS-CNC-Cu 2+ Scanning electron microscope (SEM) images of the film surface and cross-section show a uniform surface. Cross-sectional microscopy images reveal the properties of CS-CNC and CS-CNC-Cu films after 15 min of water absorption. 2+ The pore sizes differ. Specifically, to absorb the same amount of water, CS-CNC differs from CS-CNC-Cu. 2+ The pores are denser and larger, and the different pore structures lead to asymmetrical water absorption capacity, which in turn causes the film to self-deform. Figure 10 The film surface shows that the elemental distribution of C, O, and Cu is relatively uniform. Figure 11 Displaying D / CS-CNC-Cu 2+ The film exhibits good thermal stability as it begins to decompose at 230℃.

[0086] 3. Biodegradability

[0087] To evaluate the biodegradability of the materials, polyethylene (PE) film, A4 paper, polylactic acid (PLA) straws, and D / CS-CNC-Cu were used. 2+ The film was cut into 10×20 mm pieces. 2 Samples of varying sizes were placed in natural soil on the campus of Anhui University for degradation testing. The testing period was from April 10, 2025 to July 20, 2025. The experimental results are attached. Figure 12 As shown, at 15 days, D / CS-CNC-Cu 2+ The edges of the film and A4 paper have begun to gradually degrade, and the shape no longer maintains a complete rectangle. (D / CS-CNC-Cu) 2+ The surface began to degrade, while the PE film and PLA pipette showed no significant changes. After 50 days, the filter paper degradation rate reached 76%, D / CS-CNC-Cu2+ Only 27% of the film degraded, while PE film and PLA straws showed almost no degradation. After 90 days, D / CS-CNC-Cu... 2+ The film degradation rate reached 77%, and it was eventually completely degraded within 125 days, indicating that D / CS-CNC-Cu 2+ The film exhibits excellent biodegradability.

[0088] In summary, the biomass-based hydrosolid plastic disclosed in this invention is made from biomass, which is abundant, low-cost, sustainable, renewable, biodegradable, and biocompatible. Biomass-based hydrosolid plastics are molded directly through water treatment, eliminating the need for molds. They utilize only water, eliminating the need for molds and heating, simplifying the process and avoiding high-energy-consuming and high-emission processes. They do not rely on expensive or complex equipment. Furthermore, biomass-based hydrosolid plastics solve the problem of shape instability in aqueous environments found in traditional hydroplastics, extending the plastic's lifespan. In addition, biomass-based hydrosolid plastics generally possess good mechanical properties, humidity stability, and thermal stability, showing broad application prospects in packaging materials, the automotive industry, medical equipment, soft robots, electronic products, and optical devices.

[0089] The above-disclosed embodiments are merely a few specific examples of the present invention. However, the embodiments of the present invention are not limited thereto, and any variations that can be conceived by those skilled in the art should fall within the protection scope of the present invention.

Claims

1. A biomass-based water workable plastic, characterized in that, The structure of the biomass-based water-solid plastic is a water-responsive differential structure; The water-responsive differential structure includes double-layer, multi-layer, gradient structure, regional structure and structure with adjustable aspect ratio; The shape of the biomass-based water-solid plastic is water-induced self-shape deformation, and the obtained shape is a permanent shape; The raw materials of the biomass-based water-solid plastic include one or more of biomass-based polymer materials, biomass-based nanomaterials, and biomass-based natural fiber materials.

2. The biomass-based water workable plastic according to claim 1, wherein, The biomass-based polymer materials include one or more of cellulose, hemicellulose, chitin, chitosan, lignin, xylan, starch, gum, natural rubber, alginate, protein, polyhydroxyalkanoate, polylactic acid, and cyclodextrin. The biomass-based nanomaterials include one or more of cellulose nanocrystals, cellulose nanofibers, chitin nanocrystals, chitin nanofibers, bacterial cellulose, chitosan nanoparticles, nanolignin particles, starch nanocrystals, and starch nanoparticles. The biomass-based natural fiber materials include one or more of plant fibers, animal fibers, and microbial fibers.

3. A process for the preparation of a biomass-based waterworkable plastic for the preparation of a biomass-based waterworkable plastic according to any one of claims 1 to 2, characterized in that The method comprises the following steps: S1, biomass-based polymer materials and / or biomass-based nanomaterials and / or biomass-based natural fiber materials are compounded to obtain biomass-based material 1; S2, biomass-based polymer materials and / or biomass-based nanomaterials and / or biomass-based natural fiber materials are compounded to obtain biomass-based material 2; S3, the biomass-based material 1 is combined with the biomass-based material 2 to construct a water-responsive differential structure, and a biomass-based water-solid plastic is obtained.

4. The method for preparing a biomass-based aqueous solid plastic according to claim 3, characterized in that, The combination of the biomass-based material 1 and the biomass-based material 2 and the construction method of the water-responsive differential structure include one or more of chemical crosslinking, chemical modification, physical structure, and intermolecular interaction.

5. A process for the preparation of a biomass-based water workable plastic according to claim 4, characterized in that, The chemical crosslinking includes dynamic bond crosslinking and non-dynamic bond crosslinking; the chemical modification includes hydrophilic modification and hydrophobic modification.

6. The method for preparing a biomass-based aqueous solid plastic according to claim 4, characterized in that, The physical structure includes one or more of good solvent interaction, porosity, crystallinity, molecular chain orientation, and surface / interface properties; the intermolecular interaction includes one or more of hydrogen bonding, electrostatic interaction, hydrophobic interaction, van der Waals force, and ion-dipole interaction.

7. A water-solid molding method by which the shape of the biomass-based water-solid plastic according to any one of claims 1 to 2 is edited, characterized by, The method comprises the following steps: A1, shape pre-design of the water-solid plastic; A2, water treatment of the water-solid plastic; A3, drying treatment of the water-solid plastic after deformation.

8. A water solidification molding method according to claim 7, wherein The water treatment of the water-solid plastic can be completed by soaking in water, applying water, spraying, or balancing in a humid environment.

9. A water solidification molding method according to claim 7, wherein The drying treatment of the water-solid plastic includes one or more of natural drying, air blowing drying, vacuum drying, freeze drying, microwave drying, equilibrium drying in a low-humidity environment, or desiccant drying.

10. A functional product, characterized by The functional product includes a biomass-based water-solid plastic according to any one of claims 1-2.

Images