High-strength, degradable marine biomass plastic and preparation method and application thereof

Abstract

The application discloses a high-strength and degradable marine biomass plastic and a preparation method and application thereof. The preparation method comprises the following steps: providing a first mixed system comprising seaweed, water and a green and non-toxic crosslinking agent, heating the first mixed system to generate a natural high-molecular gel; heating the natural high-molecular gel to a solution state, performing film forming treatment, forming a thin film, and drying to obtain the high-strength and degradable marine biomass plastic. The marine biomass plastic prepared by the application has the advantages of high strength, high biological compatibility, low cytotoxicity, easy biodegradation and low cost, and the main raw material is obtained from the sea, so that the production process is green and environment-friendly, and the marine biomass plastic has a great application prospect in the agriculture, forestry, food packaging and daily necessities industries.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of biological plastics, and particularly relates to a high-strength and degradable marine biomass plastic as well as a preparation method and application thereof. BACKGROUND

[0002] Plastics dominate the food packaging field due to their low cost and good processability. However, most of the plastics currently used are made from petroleum, natural gas products and coal, which makes it difficult for plastic products to be degraded. In the face of the rapid increase in the use of plastics, the continuous consumption of traditional fossil raw materials, the harsh conditions in the plastic processing process and the large amount of non-degradable pollutants generated after the recycling of waste plastics, which cause serious harm to the ecological environment, agricultural development, animals and plants and human health, people are working to develop green and environmentally friendly sustainable materials to replace traditional fossil raw materials.

[0003] Biopolymers, as a kind of biodegradable material that can be obtained from renewable resources, are expected to replace synthetic polymers and become new plastic raw materials in the future. The most widely studied biopolymers are usually derived from terrestrial crops, such as thermoplastic starch and poly(lactic) acid (PLA), however, plastic materials made from starch and the like often quickly decompose in a humid environment, and cultivating crops requires constant depletion of soil nutrients. On the other hand, there have been many reports on the development of bioplastic films using waste feathers, coarse wool and other keratin materials, but such materials have a low degree of disulfide cross-linking and secondary structure, which is difficult to restore during the process of dissolving, regenerating and preparing bioplastics, thereby making keratin bioplastics have poor mechanical properties, and the preparation method is relatively complex and requires the use of many environmentally harmful chemical reagents. In summary, it is necessary to develop biopolymer materials with low cost, excellent mechanical properties and green biodegradability.

[0004] Seaweed is a natural marine biomass with abundant resources worldwide. It is rich in complex and strong long-fiber structures composed of cellulose chains and seaweed polysaccharides and other components, thereby exhibiting excellent dimensional stability and compressibility in three-dimensional structure and showing good water barrier ability with high moisture resistance. The above characteristics of seaweed make it have great development potential in producing low-cost, green and biodegradable plastics. However, in actual production, how to select suitable seaweed and cross-linking agent and determine the ratio of seaweed and cross-linking agent so as to make them have excellent mechanical properties and biodegradability is a problem to be solved. SUMMARY

[0005] The main purpose of the present application is to provide a high-strength and degradable marine biomass plastic as well as a preparation method and application thereof, so as to overcome the deficiencies in the prior art.

[0006] To achieve the aforementioned technical purposes, the technical scheme adopted by the embodiment of the present application comprises:

[0007] The embodiment of the present application provides a preparation method of high-strength and degradable marine biomass plastic, comprising:

[0008] A first mixed system containing seaweed, water and a green non-toxic crosslinking agent is provided, and the first mixed system is heated to generate a natural high molecular gel;

[0009] The natural high molecular gel is heated to a solution state, film forming treatment is performed, a film is formed, and drying is performed to obtain the high-strength and degradable marine biomass plastic.

[0010] Further, the preparation method of the high-strength and degradable marine biomass plastic further comprises: heating the natural high molecular gel to a solution state, mixing the natural high molecular gel with a filler aqueous solution to form a second mixed system, and then performing film forming treatment after heating and uniform stirring; wherein the heating temperature is 60-95℃, the heating time is 30-300min, and the stirring speed is 550-1000rpm; preferably, the film forming treatment comprises any one of casting method or blade coating method.

[0011] Further, the preparation method of the high-strength and degradable marine biomass plastic comprises: uniformly dispersing a solid filler in water to form a filler aqueous solution, and adding the filler aqueous solution to the heated natural high molecular gel in a solution state; wherein the mass percentage of the solid filler in the filler aqueous solution is 1%-10%, and the volume ratio of the filler aqueous solution to the heated natural high molecular gel in a solution state is 1:(1-3).

[0012] Further, the solid filler comprises any one of clay, montmorillonite, kaolin, bentonite, hydroxyapatite, silicate, aluminosilicate, aluminate, borate, sulfate, sulfaluminate, phosphate, ferric aluminate.

[0013] Further, the preparation method of the high-strength and degradable marine biomass plastic comprises: mixing seaweed, water and a crosslinking agent to form the first mixed system, stirring and heating, centrifuging, collecting the supernatant gel layer to obtain the natural high molecular gel; wherein the stirring speed is 550-1000rpm, the heating temperature is 75-95℃, the heating time is 30-300min, the centrifuging speed is 8000-12000rpm, and the centrifuging time is 5min-20min.

[0014] Preferably, the mass percentage of seaweed in the first mixed system is 10%-40%, and the mass percentage of the crosslinking agent is 0.5%-10%.

[0015] Further, the cross-linking agent includes any one or a combination of two or more of glycolic acid, lactic acid, mandelic acid, malic acid, phytic acid, tartaric acid, grape acid, gallic acid, tannic acid, citric acid, hyaluronic acid, gum arabic, dopamine, starch, gelatin, chitosan, cellulose, D-panthenol, polyvinyl alcohol, polyethylene glycol, polylactic acid, boric acid, and glycerol.

[0016] The cross-linking agent and the solid filler in the embodiments of the present application are derived from natural plants, minerals, land animals or marine animals, or are safe and non-toxic synthetic polymers, and have high biocompatibility, low cytotoxicity and degradability.

[0017] Further, the dry equilibrium condition is 20-30℃ and 40-70 RH% for 24-120h.

[0018] The embodiments of the present application also provide a high-strength and degradable marine biomass plastic prepared by the foregoing method, and the high-strength and degradable marine biomass plastic has a breaking strength of 1.65-52.35 MPa, an elongation at break of 1.38-50%, and a Young's modulus of 11-2890 MPa.

[0019] The embodiments of the present application also provide an application of the foregoing high-strength and degradable marine biomass plastic in the fields of agriculture, forestry, fishery, food packaging materials or daily necessities.

[0020] Compared with the prior art, the present application has the following beneficial effects:

[0021] (1) In the preparation method of the present application, the selected seaweed is rich in complex and strong long-fiber structures composed of cellulose chains and components such as seaweed polysaccharides, so that the prepared plastic has high strength, dimensional stability and compressibility, and exhibits good barrier ability to water; the introduction of appropriate cross-linking agent and solid filler further enhances the mechanical strength and stability of the polymer network structure. The seaweed, cross-linking agent and solid filler cooperate and synergize with each other, so that the marine biomass plastic has excellent mechanical properties and has great application potential in the fields of agriculture, forestry, fishery, food packaging materials or daily necessities.

[0022] (2) In the preparation method of the present application, the main raw material used is a pure natural plant derived from the ocean, and the selected cross-linking agent and solid filler are derived from natural plants, minerals, land animals or marine animals, or are safe and non-toxic synthetic polymers, and no other chemical reagents are used, so that the prepared marine biomass plastic has high biocompatibility, low cytotoxicity and excellent biodegradability; in addition, seaweed resources are abundant, and the use of seaweed as the main raw material for making plastic makes the plastic production and processing process have the advantages of low cost and green environmental protection. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a photograph of the marine biomass plastic obtained in Example 9 of the present invention.

[0025] Figure 2 The stress-strain curve of the marine biomass plastic obtained in Example 9 of the present invention is shown.

[0026] Figure 3 This is a photograph of the marine biomass plastic obtained in Example 13 of the present invention.

[0027] Figure 4 The stress-strain curve of the marine biomass plastic obtained in Example 13 of the present invention is shown. Detailed Implementation

[0028] In view of the deficiencies of existing technologies, the inventors of this invention, through long-term research and extensive practice, have proposed the technical solution of this invention. This invention uses seaweed as the main raw material to prepare marine biomass plastics, which has the advantages of simple operation, economy, environmental protection, and easy degradation. Meanwhile, seaweed is rich in long fiber structures and polysaccharides, and has relative hydrophobicity; therefore, plastics made from seaweed have high strength, dimensional stability, and compressibility, and exhibit high tolerance to humidity environments. The introduction of appropriate crosslinking agents and the filling of solid fillers can further enhance the mechanical strength and stability of the polymer network structure.

[0029] One aspect of this invention provides a method for preparing high-strength, biodegradable marine biomass plastics, comprising:

[0030] A first mixture system containing seaweed, water and a green, non-toxic crosslinking agent is provided; heating the first mixture system generates a natural polymer gel.

[0031] The natural polymer gel is heated to a solution state, subjected to film-forming treatment to form a thin film, and dried to obtain a high-strength, biodegradable marine biomass plastic.

[0032] In some preferred embodiments, the method for preparing the high-strength, degradable marine biomass plastic further comprises: heating the natural high-molecular gel to a solution state and mixing it with a filler aqueous solution to form a second mixed system, and then performing film forming treatment after heating and stirring uniformly; wherein the heating temperature is 60-95°C, the heating time is 30-300 min, and the stirring speed is 550-1000 rpm; preferably, the film forming treatment comprises any one of casting method or blade coating method.

[0033] In some preferred embodiments, the method for preparing the high-strength, degradable marine biomass plastic comprises: uniformly dispersing a solid filler in water to form a filler aqueous solution, and adding the filler aqueous solution to the heated natural high-molecular gel in a solution state; wherein the mass percentage of the solid filler in the filler aqueous solution is 1%-10%, and the volume ratio of the filler aqueous solution to the heated natural high-molecular gel in a solution state is 1:(1-3).

[0034] In some preferred embodiments, the solid filler can include any one of clay, montmorillonite, kaolin, bentonite, hydroxyapatite, silicate, aluminosilicate, aluminate, borate, sulfate, sulfaluminate, phosphate, ferric aluminate, etc., but is not limited thereto.

[0035] In some preferred embodiments, the seaweed is dry seaweed powder with a particle size of 300-800 mesh.

[0036] In some more preferred embodiments, the seaweed can include any one of red algae, brown algae, green algae, etc., but is not limited thereto.

[0037] In some preferred embodiments, the method for preparing the high-strength, degradable marine biomass plastic comprises: mixing seaweed, water and a crosslinking agent to form the first mixed system, stirring and heating, then centrifuging, collecting the supernatant gel layer, and obtaining the natural high-molecular gel; wherein the stirring speed is 550-1000 rpm, the heating temperature is 75-95°C, the heating time is 30-300 min, the centrifugation speed is 8000-12000 rpm, and the centrifugation time is 5 min-20 min.

[0038] In some more preferred embodiments, the mass percentage of the seaweed in the first mixed system is 10%-40%, and the mass percentage of the crosslinking agent is 0.5%-10%.

[0039] In some preferred embodiments, the cross-linking agent can include any one or a combination of two or more of glycolic acid, lactic acid, mandelic acid, malic acid, phytic acid, tartaric acid, vitiolic acid, gallic acid, tannic acid, citric acid, hyaluronic acid, gum arabic, dopamine, starch, gelatin, chitosan, cellulose, D-panthenol, polyvinyl alcohol, polyethylene glycol, polylactic acid, boric acid, glycerol, and the like, but is not limited thereto.

[0040] In some preferred embodiments, the dry equilibrium condition is 20-30℃ and 40-70 RH% for 24-120h.

[0041] In some preferred embodiments, the method for preparing the high-strength, degradable marine biomass plastic includes drying seaweed in an oven and grinding it into seaweed powder with a particle size of 300-800 mesh.

[0042] Another aspect of the embodiments of the present application also provides a high-strength, degradable marine biomass plastic prepared by the aforementioned method, and the high-strength, degradable marine biomass plastic has a breaking strength of 1.65-52.35 MPa, an elongation at break of 1.38-50%, and a Young's modulus of 11-2890 MPa.

[0043] Another aspect of the embodiments of the present application also provides the aforementioned high-strength, degradable marine biomass plastic for use in the fields of agriculture, forestry, fishery, food packaging materials, or daily necessities.

[0044] The technical solutions of the present application will be further described in detail below in combination with several preferred embodiments and the accompanying drawings. The embodiments are implemented on the premise of the technical solutions of the present application, and detailed implementation modes and specific operation processes are given, but the protection scope of the present application is not limited to the following embodiments.

[0045] The following embodiments all use an Instron universal material testing machine to test the tensile properties of marine biomass plastics. The sample size is 95x10mm, the clamping distance is 50mm, and the tensile speed is 10mm / min. Before testing, the thickness of the sample is first tested using an electronic digital outside diameter micrometer (two keys), and three data for each sample are tested to obtain the average thickness value. After entering the test interface, the computer will continuously collect and analyze various test data, draw the test curve in real time, automatically calculate the test parameters and output the report, record the strength and elongation value after the sample breaks, and calculate the Young's modulus of the sample according to the stress-strain curve.

[0046] Example 1

[0047] Fresh Ulva lactuca was dried in an oven and ground into 600 mesh seaweed powder by mechanical grinding. 30 g of seaweed powder was taken in a beaker, 1.5 g of hydroxypropyl methyl cellulose was added to the beaker, and 300 mL of deionized water was added to the beaker, and the mixed system was heated at 90°C for 3 h using an oil bath, and the stirring speed was 550 rpm. After heating, the solution was centrifuged at a speed of 9000 rpm for 20 min, and the supernatant gel layer was collected after centrifugation was completed. Finally, the gel layer was heated at 60°C, and after it was converted into a solution state, 10 mL was transferred to a flat disc made of polytetrafluoroethylene, and stored in an oven at 30°C until the moisture was completely evaporated, and then placed at 25°C and 55 RH% for 24 h, and the marine biomass plastic was peeled off. The breaking strength, breaking elongation and Young's modulus of the plastic were 5.32 MPa, 11%, and 179 MPa, respectively.

[0048] Example 2

[0049] This example is different from Example 1 in that the amount of crosslinking agent hydroxypropyl methyl cellulose is 5 g, and the rest is the same as Example 1. The specific as shown in Table 1. The breaking strength, breaking elongation and Young's modulus of the plastic were 7.29 MPa, 17%, and 250 MPa, respectively.

[0050] Example 3

[0051] This example is different from Example 1 in that the amount of crosslinking agent hydroxypropyl methyl cellulose is 7.5 g, and the rest is the same as Example 1. The specific as shown in Table 1. The breaking strength, breaking elongation and Young's modulus of the marine biomass plastic obtained were 8.63 MPa, 19%, and 469 MPa, respectively.

[0052] Example 4

[0053] This example is different from Example 1 in that the amount of crosslinking agent hydroxypropyl methyl cellulose is 9 g, and the rest is the same as Example 1. The specific as shown in Table 1. The breaking strength, breaking elongation and Young's modulus of the marine biomass plastic obtained were 5.17 MPa, 23%, and 198 MPa, respectively.

[0054] Example 5

[0055] This example is different from Example 1 in that the amount of crosslinking agent hydroxypropyl methyl cellulose is 30 g, and the rest is the same as Example 1. The specific as shown in Table 1. The breaking strength, breaking elongation and Young's modulus of the marine biomass plastic obtained were 5.02 MPa, 30%, and 155 MPa, respectively.

[0056] Example 6

[0057] The difference between this embodiment and embodiment 1 is that the crosslinking agent is changed from hydroxypropyl methyl cellulose to gelatin, and the amount is 5 g, and the rest is the same as embodiment 1. The specific is shown in Table 1. The breaking strength, elongation at break and Young's modulus of the obtained marine biomass plastic are 18.71 MPa, 1.96%, 680 MPa, respectively.

[0058] Example 7

[0059] The difference between this embodiment and embodiment 6 is that the amount of gelatin is 7.5 g, and the rest is the same as embodiment 6. The specific is shown in Table 1. The breaking strength, elongation at break and Young's modulus of the obtained marine biomass plastic are 22.56 MPa, 2.24%, 1068 MPa, respectively.

[0060] Example 8

[0061] The difference between this embodiment and embodiment 6 is that the amount of gelatin is 9 g, and the rest is the same as embodiment 6. The specific is shown in Table 1. The breaking strength, elongation at break and Young's modulus of the obtained marine biomass plastic are 27.73 MPa, 3%, 1443 MPa, respectively.

[0062] Example 9

[0063] The difference between this embodiment and embodiment 6 is that the amount of gelatin is 30 g, and the rest is the same as embodiment 6. The specific is shown in Table 1. The marine biomass plastic is peeled off in this embodiment, and the photo is shown in Figure 1 , and the stress-strain curve is shown in Figure 2 . The breaking strength, elongation at break and Young's modulus of the obtained marine biomass plastic are 40.97 MPa, 4.7%, 1684 MPa, respectively.

[0064] Example 10

[0065] The difference between this embodiment and embodiment 1 is that the crosslinking agent is changed from hydroxypropyl methyl cellulose to glycerol, and the amount is 3 g, and the rest is the same as embodiment 1. The specific is shown in Table 1. The breaking strength, elongation at break and Young's modulus of the obtained marine biomass plastic are 5.01 MPa, 30%, 176 MPa, respectively.

[0066] Example 11

[0067] The difference between this embodiment and embodiment 10 is that the amount of glycerol is 6 g, and the rest is the same as embodiment 10. The specific is shown in Table 1. The breaking strength, elongation at break and Young's modulus of the obtained marine biomass plastic are 4.12 MPa, 35%, 142 MPa, respectively.

[0068] Example 12

[0069] The difference between this embodiment and embodiment 10 is that the amount of glycerol is 9 g, and the rest is the same as embodiment 10. As shown in Table 1. The breaking strength, elongation at break and Young's modulus of the obtained marine biomass plastic are 3.95 MPa, 50%, 28 MPa, respectively.

[0070] Table 1

[0071]

[0072] As can be seen from Table 1, under the same amount of seaweed and preparation conditions, the type and amount of crosslinking agent have certain influence on the mechanical properties of marine biomass plastic. First, with the increase of the amount of crosslinking agent, the elongation at break of the plastic shows a trend of increase, because the crosslinking agent can weaken the intermolecular interaction of the polymer, increase the flowability of the polymer, so that the biomass plastic becomes more elastic; secondly, compared with hydroxypropyl methyl cellulose and glycerol, gelatin is more obvious for improving the mechanical properties of marine biomass plastic, which shows that gelatin is more suitable for the crosslinking system of marine biomass plastic.

[0073] Example 13

[0074] Fresh Ulva lactuca was placed in an oven and dried, and was ground into 600 mesh seaweed powder by mechanical grinding. 30 g of seaweed powder was taken in a beaker, and 5 g of gelatin and 300 mL of deionized water were added to the beaker, heated at 90°C for 3h, and the stirring speed was 550rmp. After heating, the solution was centrifuged at a speed of 9000 rpm for 20 min, and the supernatant gel layer was collected after centrifugation. Finally, the gel layer was heated, and 10 mL of the solution was taken and 3 mL of 3% clay aqueous solution was added, heated at 75°C for 30 min, and the stirring speed was 550rmp. After the system was mixed uniformly, it was transferred to a flat disc made of polytetrafluoroethylene material, and stored in an oven at 30°C until the water was completely evaporated. After drying, it was placed at 25°C and 55 RH% for 24h, and the marine biomass plastic was peeled off. The photo is shown in Figure 3 The stress-strain curve is shown in Figure 4 The breaking strength, elongation at break and Young's modulus of the plastic are 47.69 MPa, 4.69%, 1820 MPa, respectively.

[0075] Example 14

[0076] The difference between this embodiment and embodiment 13 is that the volume of clay aqueous solution (3%) is 5 mL, and the rest is the same as embodiment 13. As shown in Table 2, the breaking strength, elongation at break and Young's modulus of the plastic are 41.73 MPa, 4.01%, 1443 MPa, respectively.

[0077] Example 15

[0078] The difference between this example and Example 13 is that the volume of the clay aqueous solution (3%) is 10 mL, and the rest is the same as Example 13. As shown in Table 2, the breaking strength, breaking elongation and Young's modulus of the plastic are 23.1 MPa, 2.34%, and 1135 MPa, respectively.

[0079] Example 16

[0080] The difference between this example and Example 13 is that the volume of the clay aqueous solution is still 3 mL, but the mass fraction of the clay is increased from 3% to 8%, and the rest is the same as Example 13. As shown in Table 2, the breaking strength, breaking elongation and Young's modulus of the plastic are 38.50 MPa, 1.8%, and 1200 MPa, respectively.

[0081] Example 17

[0082] The difference between this example and Example 13 is that the volume of the clay aqueous solution is still 3 mL, but the mass fraction of the clay is increased from 3% to 10%, and the rest is the same as Example 13. As shown in Table 2, the breaking strength, breaking elongation and Young's modulus of the plastic are 11.33 MPa, 1.38%, and 957 MPa, respectively.

[0083] Table 2

[0084]

[0085]

[0086] As can be seen from Table 2, under the same seaweed, crosslinking agent addition amount and preparation conditions, the amount of solid filler has a certain influence on the mechanical properties of the marine biomass plastic. With the increase of the mass percentage of the solid filler and the volume of the filler aqueous solution, the breaking elongation of the plastic gradually decreases. When the mass fraction of the filler in the aqueous solution is 3%, and the volume ratio of the filler aqueous solution to the natural polymer gel is 1:3, the plastic can simultaneously obtain good hardness and toughness.

[0087] Example 18

[0088] Fresh Ulva lactuca was placed in an oven to dry, and was ground into 600-mesh seaweed powder by mechanical grinding. 30 g of the seaweed powder was taken in a beaker, 7.5 g of gelatin and 300 mL of deionized water were added to the beaker, heated at 90°C for 3 h, and stirred at a speed of 550 rpm. After heating, the solution was centrifuged at a speed of 9000 rpm for 20 min, and the supernatant gel layer was collected after centrifugation. Finally, 10 mL of the gel layer was heated, 3 mL of a 3% clay aqueous solution was added, heated at 75°C for 30 min, and stirred at a speed of 550 rpm. After the system was uniformly mixed, it was transferred to a flat-bottomed square dish made of polytetrafluoroethylene, and stored in an oven at 30°C until the moisture was completely evaporated. Then, it was placed at 25°C and 55% RH for 24 h, and the marine biomass plastic was peeled off. The breaking strength, elongation at break and Young's modulus of the plastic were 52.35 MPa, 13% and 2890 MPa, respectively. By comparing this example with Examples 13-17, it can be seen that appropriately increasing the amount of solid filler and crosslinking agent can synergistically enhance the mechanical properties of the marine biomass plastic.

[0089] Comparative Example 1

[0090] Fresh Ulva lactuca was placed in an oven to dry, and was ground into 600-mesh seaweed powder by mechanical grinding. 30 g of the seaweed powder was taken in a beaker, 7.5 g of gelatin and 300 mL of deionized water were added to the beaker, heated at 90°C for 3 h, and stirred at a speed of 550 rpm. After heating, the solution was centrifuged at a speed of 9000 rpm for 20 min, and the supernatant gel layer was collected after centrifugation. Finally, 10 mL of the gel layer was heated, 3 mL of a 3% clay aqueous solution was added, heated at 75°C for 30 min, and stirred at a speed of 550 rpm. After the system was uniformly mixed, it was transferred to a flat-bottomed square dish made of polytetrafluoroethylene, and stored in an oven at 30°C until the moisture was completely evaporated. Then, it was placed at 25°C and 55% RH for 24 h, and the marine biomass plastic was peeled off. The breaking strength, elongation at break and Young's modulus of the plastic were 52.35 MPa, 13% and 2890 MPa, respectively. By comparing this example with Examples 13-17, it can be seen that appropriately increasing the amount of solid filler and crosslinking agent can synergistically enhance the mechanical properties of the marine biomass plastic.

[0091] Comparative Example 2

[0092] The difference between this comparative example and Comparative Example 1 is that the seaweed used is Laminaria japonica, and the rest is the same as Comparative Example 1. The specific conditions are shown in Table 1.

[0093] Comparative Example 3

[0094] The difference between this comparative example and Comparative Example 1 is that the seaweed used is Undaria pinnatifida, and the rest is the same as Comparative Example 1. The specific conditions are shown in Table 3.

[0095] Table 3

[0096]

[0097] As can be seen from Table 3, under the same seaweed addition amount and preparation conditions, the mechanical properties of Ulva algae belonging to Chlorophyta are better, which indicates that green algae is more suitable as a raw material for marine biomass plastics; at the same time, by comparing Comparative Examples 1-3 with Examples 1-18, it can be seen that the addition of crosslinking agent and solid filler can effectively enhance the mechanical properties of marine biomass plastics.

[0098] In addition, the inventors of the present case also refer to the foregoing examples, and other raw materials, process operations, process conditions described in the specification are tested, and ideal results are obtained.

[0099] Although the present application has been described with reference to illustrative examples, it will be understood by those skilled in the art that various other changes, omissions, and / or additions can be made and elements of the examples can be substituted with substantial equivalents without departing from the spirit and scope of the present application. In addition, many modifications can be made to adapt a particular situation or material to the teachings of the present application without departing from the scope thereof. Therefore, it is intended that the present application not be limited to the disclosed particular embodiments implementing the present application, but that the present application will include all embodiments falling within the scope of the appended claims. Furthermore, unless specifically stated, any use of the terms first, second, etc. does not indicate any order or importance, but rather the use of the terms first, second, etc. is merely to identify one element from another element.

Claims

1. A method for preparing a high-strength, biodegradable marine biomass plastic, characterized in that, include: A first mixed system comprising seaweed, water and a green and non-toxic crosslinking agent is provided, wherein the seaweed is Ulva lactuca and its mass percentage is 10% to 40%, and the crosslinking agent is gelatin and its mass percentage is 1.6% to 10%. The first mixed system is heated to 75 to 95°C and maintained for 30 to 300 minutes to generate a natural polymer gel. The natural polymer gel is heated to a solution state and mixed with a filler aqueous solution to form a second mixed system; wherein the solid filler contained in the filler aqueous solution is clay, with a mass percentage of 1% to 10%, and the volume ratio of the filler aqueous solution to the heated solution state natural polymer gel is 1: (1~3). The second mixing system is heated to 60~95℃ and maintained for 30~300min, and stirred evenly at a speed of 550~1000rpm. Then, a film-forming treatment is performed to form a thin film, and the film is dried and balanced to obtain a high-strength, biodegradable marine biomass plastic.

2. The method for preparing high-strength, biodegradable marine biomass plastic according to claim 1, characterized in that: The film-forming process includes either casting or coating.

3. The method for preparing high-strength, biodegradable marine biomass plastic according to claim 1, characterized in that, The seaweed is a dried seaweed powder with a particle size of 300-800 mesh.

4. The method for preparing high-strength, biodegradable marine biomass plastic according to claim 1, characterized in that, include: The seaweed, water, and crosslinking agent are mixed to form the first mixed system. After stirring and heating, the mixture is centrifuged, and the supernatant gel layer is collected to obtain a natural polymer gel. The stirring speed is 550~1000 rpm, the centrifugation speed is 8000~12000 rpm, and the time is 5min~20min.

5. The method for preparing high-strength, biodegradable marine biomass plastic according to claim 1, characterized in that, The drying conditions are: placing the product at 20~30℃ and 40~70RH% for 24~120 hours.

6. A high-strength, biodegradable marine biomass plastic, characterized in that, The high-strength, biodegradable marine biomass plastic is prepared by any one of the methods described in claims 1-5, and has a tensile strength of 1.65~52.35 MPa, an elongation at break of 1.38~50%, and a Young's modulus of 11~2890 MPa.

7. The application of the high-strength, biodegradable marine biomass plastic of claim 6 in the fields of agriculture, forestry, fisheries, food packaging materials or daily necessities.

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