A biodegradable in-situ nanocomposite material, and a preparation method and application thereof

Abstract

The application relates to the field of biodegradable materials, and discloses a biodegradable in-situ nanocomposite material as well as a preparation method and application thereof. The nanocomposite material comprises a first resin and a second resin; the first resin comprises nanofillers with a mass fraction of 0.1-15% and a resin with a mass fraction of 85-99.9% and a number average molecular weight of 500-10,000 kDa; and the second resin comprises a resin with a number average molecular weight of 10,000-100,000 kDa. In the nanocomposite material, the nanofillers are dispersed in the first resin with a low molecular weight, the first resin is prepared by using an in-situ synthesis method, and then the first resin is mixed with the second resin with a high molecular weight, so that the nanofillers can be effectively prevented from agglomerating, the mechanical properties of the nanocomposite material can be improved, and the effects of reinforcement and toughening can be achieved.

Description

Technical Field

[0001] This invention relates to the field of biodegradable materials, and more particularly to a biodegradable in-situ nanocomposite material, its preparation method, and its application. Background Technology

[0002] With the increasing severity of "white pollution," the preparation and application of biodegradable materials have received growing attention. Biodegradable polymers are polymer materials that can be degraded by microorganisms (such as fungi, bacteria, algae, etc.) or their secretions under certain time and appropriate natural conditions through enzymatic or chemical decomposition. Currently, commercially available biodegradable polymers mainly include aliphatic polyesters, polyvinyl alcohol, and polysaccharides.

[0003] Currently, widely used biodegradable polymers mainly include polybutylene adipate / terephthalate (PBAT), poly(butylene succinate-co-butylene adipate) (PBSA), polylactic acid (PLA), polycaprolactone (PCL), polyhydroxy fatty acids (PHAs), polybutylene succinate (PBS), polyglycolic acid (PGA), polypropylene carbonate (PPC), and polybutylene succinate / terephthalate (PBST). However, because their price is 2-3 times that of ordinary industrial plastics, if they are thinned to reduce costs, their mechanical properties cannot meet market demands, thus hindering their widespread promotion and application in the market.

[0004] Currently, the mechanical properties of polymers can often be improved by adding nanoparticles. However, nanoparticles have small particle sizes and large specific surface areas, making them prone to aggregation, which leads to a decrease in mechanical properties. In-situ polymerization is typically used to copolymerize nanoparticles with polymers, effectively dispersing the nanoparticles within the polymer to obtain nanocomposite polymers containing nanoparticles.

[0005] Chinese patent application CN201410519180.4 discloses a method for preparing a sisal cellulose nanofiber / polylactic acid (PLA) biocomposite material. This method disperses sisal cellulose nanofibers in PLA via in-situ polymerization, but suffers from the problem of uniform dispersion of the nanofibers in PLA, affecting the mechanical properties of the composite material. Chinese patent application CN201610177805.2 discloses a method for preparing a sisal cellulose nanofiber-reinforced PLA / polyethylene succinate (PEG) biocomposite material. This method dissolves the sisal cellulose nanofiber / PLA composite in ethanol, blends it with PEG via solution blending, and then spins the ethanol solution of the blend. This method is not suitable for melt blending processing. Chinese patent document with application number CN201410140289.7 reports a biodegradable polyester / cellulose nanocomposite material, its preparation method and application. The method increases the compatibility between polycaprolactone and cellulose by using a compatibilizer, but does not involve the in-situ polymerization of cellulose in cyclocaprolactone. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a biodegradable in-situ nanocomposite material, its preparation method, and its applications. In this invention's nanocomposite material, by dispersing nanofillers in a low-molecular-weight first resin, and then mixing the first resin with a higher-molecular-weight second resin, the aggregation of nanofillers can be effectively prevented, improving the mechanical properties of the nanocomposite material and simultaneously achieving a strengthening and toughening effect.

[0007] The specific technical solution of this invention is as follows:

[0008] A biodegradable in-situ nanocomposite material includes a first resin and a second resin; the first resin includes 0.1-15% by mass of nanofiller and 85-99.9% by mass of resin with a number average molecular weight of 500-10,000 kDa; the second resin includes resin with a number average molecular weight of 10,000-100,000 kDa.

[0009] This invention disperses nanofillers in a low-molecular-weight first resin, then mixes the first resin with a second resin. This effectively prevents nanofiller agglomeration, improves the mechanical properties of the nanocomposite material, and simultaneously achieves a strengthening and toughening effect. The low molecular weight of the first resin facilitates the dispersion of the nanofillers and prevents agglomeration; the high molecular weight of the second resin provides better mechanical properties; and the first and second resins have good compatibility, ensuring uniform dispersion of the nanofillers during mixing. Under the combined effect of the higher molecular weight second resin and the uniformly dispersed nanofillers, the nanocomposite material of this invention exhibits superior mechanical properties.

[0010] Preferably, the preparation process of the first resin is as follows:

[0011] Option A:

[0012] Aliphatic diols, aliphatic polyols, diacids, and nanofillers are subjected to in-situ melt polycondensation at 150 ºC-280 ºC to obtain a melt polycondensation product; reaction aids are added to the melt polycondensation product, and after mixing evenly, the first resin is obtained.

[0013] Option B:

[0014] In-situ polymerization of lactones and / or lactones and nanofillers is carried out at 80 ºC-180 ºC to obtain the polymerization product; reaction aids are added to the polymerization product and mixed evenly to obtain the first resin.

[0015] Preparing the first resin via in-situ melt polycondensation or in-situ polymerization can improve the dispersibility of nanofillers within the first resin. The lower molecular weight of the first resin further facilitates the dispersion of nanofillers through in-situ melt polycondensation or in-situ polymerization.

[0016] As a preferred embodiment, in Scheme A, the preparation process of the second resin is as follows: aliphatic diol, aliphatic polyol, and diacid are subjected to melt polycondensation at 150 ºC-280 ºC to obtain a melt polycondensation product; a reaction aid is added to the melt polycondensation product, and after mixing evenly, the second resin is obtained.

[0017] In Scheme B, the preparation process of the second resin is as follows: the lactone and / or lactone are polymerized at 80 ºC-180 ºC to obtain the polymer product; a reaction aid is added to the polymer product, and after mixing evenly, the second resin is obtained.

[0018] Preferably, the mass ratio of the first resin to the second resin is 1-10:1-100.

[0019] The first resin can improve the mechanical properties of nanocomposites through nanofillers, but its excessive content can affect the effect of the second resin. The second resin has a larger molecular weight, which can improve the mechanical properties of nanocomposites, but its excessive content can affect the effect of the first resin. By controlling the mass ratio of the first resin to the second resin, nanocomposites with different mechanical properties can be obtained.

[0020] Preferably, the nanofiller is one or more of cellulose, cellulose nanocrystals, cellulose nanofibers, lignin, alkaline lignin, and halloysite, with an aspect ratio of 10-1000.

[0021] Preferably, in the preparation process of the first resin of Scheme A and / or the preparation process of the second resin of Scheme A, the molar ratio of the aliphatic diol, aliphatic polyol and diacid is 10-200:0-10:5-90.

[0022] Preferably, in the preparation process of the first resin of Scheme A and / or the preparation process of the second resin of Scheme A, the mass of the nanofiller is 0.1-15% of the total mass of the aliphatic diol, aliphatic polyol and diacid.

[0023] Preferably, during the preparation of the first resin in Scheme A and / or the second resin in Scheme A, a polycondensation reaction catalyst is added during the melt polycondensation process.

[0024] Furthermore, the molar ratio of the polycondensation catalyst to the dicarboxylic acid is 1-10:1000.

[0025] Furthermore, the catalyst for the polycondensation reaction is one or more of tetrabutyl titanate, antimony glycolate, antimony acetate, and antimony trioxide.

[0026] Preferably, in the preparation of the first resin of Scheme A and / or the preparation of the second resin of Scheme A, the mass of the reaction aid is 0.1-5% of the mass of the melt polycondensation product.

[0027] Preferably, in the preparation process of the first resin of Scheme A and / or the preparation process of the second resin of Scheme A, the aliphatic diol is C2-C6. 20 One or more of the straight-chain or branched aliphatic diols.

[0028] Furthermore, the aliphatic diol is one or more of C2-C8 straight-chain or branched aliphatic diols.

[0029] C2-C 20 Straight-chain or branched aliphatic diols, such as ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,2-butanediol, hexanediol, 1,4-cyclohexanediol, 1,3-cyclohexanediol, etc.

[0030] Preferably, in the preparation process of the first resin of Scheme A and / or the preparation process of the second resin of Scheme A, the aliphatic polyol is one or more of glycerol, trimethylolethane, pentaerythritol, xylitol, and sorbitol.

[0031] Preferably, in the preparation process of the first resin of Scheme A and / or the preparation process of the second resin of Scheme A, the dicarboxylic acid is composed of an aliphatic dicarboxylic acid and an aromatic dicarboxylic acid.

[0032] Furthermore, the aliphatic dicarboxylic acid accounts for 30-70% of the total mass of the dicarboxylic acid.

[0033] Furthermore, the aliphatic dicarboxylic acid is C2-C. 10 One or more of the aliphatic dicarboxylic acids.

[0034] Furthermore, the aliphatic dicarboxylic acid is one or more of the C2-C8 aliphatic dicarboxylic acids.

[0035] C2-C 10 Aliphatic dicarboxylic acids, such as malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, octanoic acid, sebacic acid, 2,3-dimethylglutaric acid, diethylene glycol, etc.

[0036] Furthermore, the aromatic dicarboxylic acid is C8-C. 12 One or more of the aromatic dicarboxylic acids.

[0037] Furthermore, the aromatic dicarboxylic acid is one or more of the C8 aromatic dicarboxylic acids.

[0038] C8-C 12 Aromatic dicarboxylic acids, such as terephthalic acid, isophthalic acid, phthalic acid, biphenyl acid, 2,6-naphthalenedicarboxylic acid, or 1,5-naphthalenedicarboxylic acid.

[0039] Preferably, in the preparation process of the first resin of Scheme A and / or the preparation process of the second resin of Scheme A, the reaction aid is one or more of aziridine, epoxy, isocyanate, titanate, and oxazoline.

[0040] Preferably, during the preparation of the first resin of Scheme B and / or the second resin of Scheme B, a polymerization catalyst is added during the polymerization process.

[0041] Furthermore, the ratio of the amount of the polymerization catalyst to the total amount of lactone and lactone is 1-10:1000.

[0042] Furthermore, the polymerization catalyst is one or more of aluminum chloride, stannous chloride, stannous isooctanoate, zinc acetate, and ethylaluminoxane.

[0043] Preferably, in the preparation of the first resin of Scheme B and / or the preparation of the second resin of Scheme B, the mass of the reaction aid is 0.1-5% of the mass of the polymerization product.

[0044] Preferably, in the preparation process of the first resin of Scheme B and / or the preparation process of the second resin of Scheme B, the lactone and / or lactide have 2 to 6 carbon atoms.

[0045] Preferably, in the preparation of the first resin of Scheme B and / or the preparation of the second resin of Scheme B, the reaction aid is one or more of aziridine, epoxy, isocyanate, titanate, and oxazoline.

[0046] Preferably, the preparation of the first resin and the second resin is carried out in one of the following: a tubular reactor, a batch reactor, or a screw reactor.

[0047] A method for preparing the above-mentioned biodegradable in-situ nanocomposite material includes the following steps:

[0048] (1) Preparation of the first resin;

[0049] (2) Preparation of the second resin;

[0050] (3) Blending: The first resin and the second resin are blended in a screw extruder to obtain a biodegradable in-situ nanocomposite material; or the first resin is added to the second resin and blended to obtain a biodegradable in-situ nanocomposite material.

[0051] A method for preparing biodegradable materials using the above-mentioned nanocomposite material or the nanocomposite material prepared by the above-mentioned preparation method includes the following steps: mixing the nanocomposite material with a biodegradable polyester at a mass ratio of 1-10:1-100, and then processing the mixture to obtain the biodegradable material.

[0052] The nanocomposite material of this invention is mixed with a biodegradable polyester. The first resin in the nanocomposite material promotes good dispersion of the nanofiller in the biodegradable resin, while the second resin improves the compatibility between the nanofiller and the biodegradable polyester and enhances their interaction. This results in better mechanical properties of the biodegradable material, while also achieving a strengthening and toughening effect. Experiments show that, compared to the biodegradable resin, the biodegradable material prepared by adding the nanocomposite material exhibits a 10-100% increase in Young's modulus, tensile strength, and elongation at break.

[0053] Preferably, the biodegradable polyester is one or more of polybutylene adipate / terephthalate (PBAT), polylactic acid (PLA), polycaprolactone (PCL), polyglycolic acid (PGA), polypropylene carbonate (PPC), polybutylene succinate (PBS), polybutylene succinate / terephthalate (PBST), polyhydroxyalkanoates (PHA), polyethylene succinate / terephthalate (PEST), and polyethylene adipate / terephthalate (PEAT).

[0054] Preferably, the processing method is one of the following: blown film method, cast film method, solution casting method, spin coating method, calendering method, multilayer co-extrusion method, biaxial stretching method, and lamination method.

[0055] Preferably, the biodegradable material is one of the following: film, sheet, or plate.

[0056] Compared with the prior art, the present invention has the following advantages:

[0057] (1) In the nanocomposite material of the present invention, by dispersing the nanofiller in a low molecular weight first resin and then mixing the first resin with a higher molecular weight second resin, the agglomeration of the nanofiller can be effectively prevented, the mechanical properties of the nanocomposite material can be improved, and the strengthening and toughening effects can be achieved at the same time.

[0058] (2) In the nanocomposite material of the present invention, the first resin is prepared by in-situ melt polycondensation or in-situ polymerization, which can improve the dispersibility of nanofillers in the first resin, thereby improving the mechanical properties of the nanocomposite material.

[0059] (3) In the nanocomposite material of the present invention, by adjusting the amount of nanofiller added and the mass ratio of the first and second resins, nanocomposite materials with different mechanical properties can be obtained.

[0060] (4) When the nanocomposite material of the present invention is used to prepare biodegradable materials, the second resin with a larger molecular weight also has the effect of improving the compatibility between the nanofiller and the biodegradable polyester, and the biodegradable material obtained has better mechanical properties.

[0061] (5) The nanocomposite material of the present invention combines biodegradability and mechanical properties, has a simple production process, and is suitable for large-scale production. Detailed Implementation

[0062] The present invention will be further described below with reference to embodiments.

[0063] Example 1

[0064] A biodegradable material is prepared by the following steps:

[0065] (1) Preparation of the first resin:

[0066] (1.1) A slurry was prepared by mixing 1.00 mol of terephthalic acid, 2.5 mol of adipic acid, 3.0 mol of 1,4-butanediol, 0.05 mol of glycerol, and 0.08 mol of pentaerythritol with an aspect ratio of 50 and a mass fraction of 0.6% of the total mass of aliphatic diols, aliphatic polyols, and dicarboxylic acids. The slurry was transported to a raw material storage tank at 70 °C. The slurry in the raw material storage tank was continuously transported to the esterification reactor through a raw material delivery pipeline. At the same time, a solution containing 0.004 mol of tetrabutyl titanate at 75 °C was transported from the catalyst pipeline. The reaction temperature inside the esterification reactor was 158 °C under a normal pressure nitrogen atmosphere. Esterification water, by-products, and the remaining polymerized monomer mixture were collected in the distillation column container through pipelines, and the system was kept stable. When the esterification rate reached more than 90%, the pressure was reduced to 100 Pa, and the temperature was increased to 250 °C. Continue the reaction at ºC for 1 hour;

[0067] (1.2) After the melt polycondensation is completed, a reaction aid (aziridine selected) at a mass of 0.4% of the melt polycondensation product mass is added to the melt polycondensation product. After stirring evenly, the mixture is fed to a screw extruder granulator for granulation to obtain the first resin; the density of the first resin is 1.24-1.27 g / cm³. 3 The number-average molecular weight is 970-1270 kDa, and the melting point is not less than 114 ºC;

[0068] (2) Preparation of the second resin:

[0069] (2.1) 1.00 mol of terephthalic acid, 1.5 mol of adipic acid, 3.0 mol of 1,4-ethylene glycol, 0.05 mol of xylitol, and 0.2 mol of sorbitol were mixed to obtain a slurry. The slurry was transported to a raw material storage tank at 70 °C. The slurry in the raw material storage tank was continuously transported to the esterification reactor through a raw material delivery pipeline. At the same time, a solution containing 0.007 mol of antimony glycol at 75 °C was transported from the catalyst pipeline. The reaction temperature inside the esterification reactor was 180 °C under a normal pressure nitrogen atmosphere. Esterification water, by-products, and the remaining polymerized monomer mixture were collected through pipelines into the distillation column container, and the system was kept stable. When the esterification rate reached more than 90%, the pressure was reduced to 100 Pa, the temperature was increased to 240 °C, and the reaction continued for 3 hours.

[0070] (2.2) After melt polycondensation is completed, a reaction aid (1,6-hexamethylene diisocyanate) at a mass of 1% of the melt polycondensation product is added to the product. After stirring evenly, the mixture is fed to a screw extruder for granulation to obtain a second resin. The density of the second resin is 1.24-1.27 g / cm³. 3The number-average molecular weight is 14,500-17,500 kDa, and the melting point is not less than 114 ºC;

[0071] (3) The first resin and the second resin are continuously mixed and extruded in a screw extruder at a mass ratio of 1:20, and then conveyed to a screw extrusion granulator by a feeder to granulate, so as to obtain a biodegradable in-situ nanocomposite material.

[0072] (4) 90.5% by mass of biodegradable polyester (polyethylene terephthalate / butyl terephthalate) and 9.5% by mass of biodegradable in-situ nanocomposite material are continuously mixed and extruded in a screw extruder, blown into a film, and wound up to obtain a biodegradable film.

[0073] The composite film obtained through the above steps has a thickness of 18 μm. According to standard GB1040-2006 "Determination of Tensile Properties of Plastics", the tensile strength of the biodegradable polyester, tested by a universal testing machine, reaches 30 MPa, the elastic modulus reaches 70 MPa, and the elongation at break is approximately 500%. The tensile strength of the biodegradable film can reach 40 MPa, the elastic modulus can reach 77 MPa, and the elongation at break is approximately 600%.

[0074] Example 2

[0075] (1) Preparation of the first resin:

[0076] (1.1) A slurry was prepared by mixing 1.00 mol of terephthalic acid, 1.5 mol of succinic acid, 3.0 mol of ethylene glycol, 0.05 mol of pentaerythritol, and 0.2 mol of trimethylolethane with a mass fraction of 9.5% of the total mass of aliphatic diols, aliphatic polyols, and diacids, with a particle size of 100. The slurry was transported to a raw material storage tank at 70 °C. The slurry in the raw material storage tank was continuously transported to the esterification reactor through a raw material transport pipeline. At the same time, 0.024 mol of antimony glycol 75 °C was transported from the catalyst pipeline. The reaction temperature inside the esterification reactor was 180 °C under a normal pressure nitrogen atmosphere. Esterification water, by-products, and the remaining polymerized monomer mixture were collected in the distillation column container through the pipeline, and the system was kept stable. When the esterification rate reached more than 90%, the pressure was reduced to 100 Pa, and the temperature was increased to 274 °C. Continue the reaction at ºC for 2.5 hours;

[0077] (1.2) After the melt polycondensation is completed, a reaction aid (2,2-(1,4-propylidene)dioxazoline) is added to the melt polycondensation product at a mass of 3.5% of the product's mass. After stirring evenly, the mixture is fed to a screw extruder for granulation to obtain the first resin. The density of the first resin is 1.24-1.27 g / cm³.3 The number-average molecular weight is 8500-9525 kDa, and the melting point is not less than 114 ºC;

[0078] (2) Preparation of the second resin:

[0079] (2.1) 1.00 mol of terephthalic acid, 0.5 mol of succinic acid, 3.5 mol of ethylene glycol, 0.05 mol of xylitol and 0.2 mol of sorbitol were mixed to obtain a slurry. The slurry was transported to the raw material storage tank at 70 °C. The slurry in the raw material storage tank was continuously transported to the esterification reactor through the raw material delivery pipeline. At the same time, a solution containing 0.007 mol of antimony glycol at 75 °C was transported from the catalyst pipeline. The reaction temperature inside the esterification reactor was 180 °C and the atmosphere was atmospheric nitrogen. Esterification water, by-products and the remaining polymer monomer mixture were collected in the distillation column container through the pipeline and the system was kept stable. When the esterification rate reached more than 90%, the pressure was reduced to 100 Pa and the temperature was increased to 270 °C. The reaction was continued for 6 hours.

[0080] (2.2) After the melt polycondensation is completed, a reaction aid (tert-butyl hydrogen peroxide) of 4.8% by mass of the melt polycondensation product is added to the product. After stirring evenly, the mixture is fed to a screw extruder for granulation to obtain the second resin. The density of the second resin is 1.24-1.27 g / cm³. 3 The number-average molecular weight is 90,500-95,500 kDa, and the melting point is not less than 114 ºC;

[0081] (3) The first resin and the second resin are continuously mixed and extruded in a screw extruder at a mass ratio of 9.5:1, and then conveyed to a screw extrusion granulator for granulation through a feeder to obtain a biodegradable in-situ nanocomposite material.

[0082] (4) 91.5% by mass of biodegradable polyester (poly(butylene succinate) / ethylene terephthalate) and 8.5% by mass of biodegradable in-situ nanocomposite material are continuously mixed and extruded in a screw extruder and then spin-coated to form a film, thus obtaining a biodegradable film.

[0083] The composite film obtained through the above steps has a thickness of 38 μm. According to standard GB1040-2006 "Determination of Tensile Properties of Plastics", the tensile strength of the biodegradable polyester, tested by a universal testing machine, reaches 32 MPa, the elastic modulus reaches 90 MPa, and the elongation at break is approximately 450%. The tensile strength of the biodegradable film reaches 45 MPa, the elastic modulus reaches 105 MPa, and the elongation at break is approximately 620%.

[0084] Example 3

[0085] (1) Preparation of the first resin:

[0086] (1.1) A slurry was prepared by mixing 1.00 mol of terephthalic acid, 1.5 mol of succinic acid, 3.0 mol of butanediol, 0.05 mol of xylitol, and 0.2 mol of sorbitol, along with cellulose nanocrystals with an aspect ratio of 20 and cellulose nanofibers with an aspect ratio of 80, which accounted for 2% of the total mass of aliphatic diols, aliphatic polyols, and dicarboxylic acids, at a mass ratio of 1:1. The slurry was then transported to a raw material storage tank at 70 °C. The slurry in the raw material storage tank was continuously transported to the esterification reactor through a raw material delivery pipeline. Simultaneously, 0.012 mol of antimony glycolate was transported from the catalyst pipeline at 75 °C. The reaction temperature inside the esterification reactor was 200 °C under a normal pressure nitrogen atmosphere. Esterification water, byproducts, and the remaining polymerized monomer mixture were collected through pipelines and placed in the distillation column container. The system was kept stable until the esterification rate reached over 90%, at which point the pressure was reduced to 100 °C. Under Pa conditions, the temperature was increased to 270 ºC, and the reaction was continued for 2.5 hours;

[0087] (1.2) After the melt polycondensation is completed, a reaction aid (diphenylmethane diisocyanate) of 1.4% by mass of the melt polycondensation product is added to the melt polycondensation product. After stirring evenly, the mixture is fed to a screw extruder granulator for granulation to obtain the first resin; the density of the first resin is 1.24-1.27 g / cm³. 3 The number-average molecular weight is 2500-3700 kDa, and the melting point is not less than 114 ºC;

[0088] (2) Preparation of the second resin:

[0089] (2.1) 1.00 mol of terephthalic acid, 0.5 mol of succinic acid, 4.0 mol of butanediol, 0.12 mol of xylitol and 0.15 mol of sorbitol were mixed to obtain a slurry. The slurry was transported to the raw material storage tank at 70 °C. The slurry in the raw material storage tank was continuously transported to the esterification reactor through the raw material delivery pipeline. At the same time, a solution containing 0.01 mol of antimony acetate at 75 °C was transported from the catalyst pipeline. The reaction temperature inside the esterification reactor was 180 °C and the atmosphere was atmospheric nitrogen. Esterification water, by-products and the remaining polymer monomer mixture were collected in the distillation column container through the pipeline and the system was kept stable. When the esterification rate reached more than 90%, the pressure was reduced to 100 Pa and the temperature was increased to 240 °C. The reaction was continued for 4 hours.

[0090] (2.2) After the melt polycondensation is completed, add 2.3% by mass of the melt polycondensation product as a reaction aid (ethylene oxide is selected), and stir evenly to obtain the second resin; the density of the second resin is 1.24-1.27 g / cm³. 3 The number-average molecular weight is 20900-31500 kDa, and the melting point is not less than 114 ºC;

[0091] (3) The first resin and the second resin are continuously mixed and extruded in a screw extruder at a mass ratio of 1:70, and then conveyed to a screw extrusion granulator for granulation through a feeder to obtain a biodegradable in-situ nanocomposite material.

[0092] (4) 95% biodegradable polyester (polybutylene succinate / butylene terephthalate and polyhydroxy fatty acid ester in a mass ratio of 10:1) and 5% biodegradable in-situ nanocomposite material are continuously mixed and extruded in a screw extruder and hot-pressed into a film to obtain a biodegradable film.

[0093] The composite film obtained through the above steps has a thickness of 200 μm. According to standard GB1040-2006 "Determination of Tensile Properties of Plastics", the tensile strength of the biodegradable polyester, tested by a universal testing machine, reaches 50 MPa, the elastic modulus reaches 85 MPa, and the elongation at break is approximately 300%. The tensile strength of the biodegradable film reaches 67 MPa, the elastic modulus reaches 100 MPa, and the elongation at break is approximately 400%.

[0094] Example 4

[0095] (1) Preparation of the first resin:

[0096] (1.1) A slurry was prepared by mixing 1.00 mol of terephthalic acid, 2.3 mol of adipic acid, 4.5 mol of ethylene glycol, 0.5 mol of glycerol, and 0.2 mol of sorbitol, along with halloysite with an aspect ratio of 20 and cellulose nanofibers with an aspect ratio of 95, which together constituted 8% of the total mass of aliphatic diols, aliphatic polyols, and dicarboxylic acids, at a mass ratio of 2:3. The slurry was then transported to a raw material storage tank at 70 °C. The slurry in the raw material storage tank was continuously transported to the esterification reactor through a raw material delivery pipeline. Simultaneously, 0.008 mol of antimony trioxide was transported from the catalyst pipeline at 75 °C. The reaction temperature inside the esterification reactor was 220 °C under a normal pressure nitrogen atmosphere. Esterification water, byproducts, and the remaining polymerized monomer mixture were collected through pipelines and placed in the distillation column container. The system was kept stable until the esterification rate reached over 90%, at which point the pressure was reduced to 100 °C. Under Pa conditions, the temperature was increased to 265 ºC, and the reaction was continued for 1.5 hours;

[0097] (1.2) After melt polycondensation is completed, a reaction aid (diphenylmethane diisocyanate) at a mass of 3.8% of the melt polycondensation product is added to the product. After stirring evenly, the mixture is fed to a screw extruder for granulation to obtain the first resin. The density of the first resin is 1.24-1.27 g / cm³. 3 The number-average molecular weight is 3500-4800 kDa, and the melting point is not less than 114 ºC;

[0098] (2) Preparation of the second resin:

[0099] (2.1) 1.00 mol of terephthalic acid, 0.5 mol of adipic acid, 4.0 mol of butanediol, 0.2 mol of xylitol and 0.15 mol of sorbitol were mixed to obtain a slurry. The slurry was transported to the raw material storage tank at 70 °C. The slurry in the raw material storage tank was continuously transported to the esterification reactor through the raw material delivery pipeline. At the same time, a solution containing 0.01 mol of antimony acetate at 75 °C was transported from the catalyst pipeline. The reaction temperature inside the esterification reactor was 190 °C and the atmosphere was atmospheric nitrogen. Esterification water, by-products and the remaining polymer monomer mixture were collected in the distillation column container through the pipeline and the system was kept stable. When the esterification rate reached more than 90%, the pressure was reduced to 100 Pa and the temperature was increased to 260 °C. The reaction was continued for 5 hours.

[0100] (2.2) After melt polycondensation is completed, add 4.2% (by mass of the melt polycondensation product) of a reaction aid (ethylene oxide) to the melt polycondensation product. After stirring evenly, a second resin is obtained. The density of the second resin is 1.24-1.27 g / cm³. 3 The number-average molecular weight is 50900-54500 kDa, and the melting point is not less than 114 ºC;

[0101] (3) The first resin is added to the reaction device of the second resin at a mass ratio of 2:1 to the second resin, stirred evenly, and then conveyed to the screw extruder granulator through the feeder for granulation to obtain a biodegradable in-situ nanocomposite material.

[0102] (4) 93% biodegradable polyester (poly(diethylene adipate / ethylene terephthalate) and 7% biodegradable in-situ nanocomposite material) are continuously mixed and extruded in a screw extruder and cast into sheets to obtain a biodegradable film.

[0103] The composite film obtained through the above steps has a thickness of 2000 μm. According to standard GB1040-2006 "Determination of Tensile Properties of Plastics", the tensile strength of the biodegradable polyester, tested by a universal testing machine, reaches 30 MPa, the elastic modulus reaches 70 MPa, and the elongation at break is approximately 600%. The tensile strength of the biodegradable film reaches 49 MPa, the elastic modulus reaches 100 MPa, and the elongation at break is approximately 900%.

[0104] Example 5

[0105] (1) Preparation of the first resin:

[0106] (1.1) 1.00 mol of terephthalic acid, 2.0 mol of adipic acid, 4.0 mol of ethylene glycol, 0.1 mol of glycerol and 0.2 mol of trimethylolethane, and lignin with a mass fraction of 6% of the total mass of aliphatic diols, aliphatic polyols and dicarboxylic acids were mixed to obtain a slurry. The slurry was transported to a raw material storage tank at 70 °C. The slurry in the raw material storage tank was continuously transported to the esterification reactor through a raw material transport pipeline. At the same time, 0.018 mol of antimony trioxide was transported from the catalyst pipeline at 75 °C. The reaction temperature inside the esterification reactor was 220 °C under normal pressure and nitrogen atmosphere. Esterification water, by-products and the remaining polymer monomer mixture were collected in the distillation column container through the pipeline and the system was kept stable. When the esterification rate reached more than 90%, the pressure was reduced to 100 Pa and the temperature was increased to 262 °C. The reaction was continued for 2.5 hours.

[0107] (1.2) After melt polycondensation is completed, a reaction aid (diphenyl diisocyanate) at a mass of 2.1% of the melt polycondensation product mass is added to the product. After stirring evenly, the mixture is fed to a screw extruder for granulation to obtain the first resin. The density of the first resin is 1.24-1.27 g / cm³. 3 The number-average molecular weight is 5500-6700 kDa, and the melting point is not less than 114 ºC;

[0108] (2) Preparation of the second resin:

[0109] (2.1) 1.00 mol of terephthalic acid, 1.5 mol of succinic acid, 3.9 mol of butanediol, 0.14 mol of xylitol and 0.1 mol of glycerol were mixed to obtain a slurry. The slurry was transported to the raw material storage tank at 70 °C. The slurry in the raw material storage tank was continuously transported to the esterification reactor through the raw material conveying pipeline. At the same time, a solution containing 0.01 mol of antimony acetate at 75 °C was transported from the catalyst pipeline. The reaction temperature inside the esterification reactor was 215 °C and the atmosphere was atmospheric nitrogen. Esterification water, by-products and the remaining polymer monomer mixture were collected in the distillation column container through the pipeline and the system was kept stable. When the esterification rate reached more than 90%, the pressure was reduced to 100 Pa and the temperature was increased to 255 °C. The reaction was continued for 5 hours.

[0110] (2.2) After melt polycondensation is completed, add 4.0% (by mass of the melt polycondensation product) of a reaction aid (propylene oxide), and stir until homogeneous to obtain the second resin. The density of the second resin is 1.24-1.27 g / cm³. 3 The number-average molecular weight is 60900-68500 kDa, and the melting point is not less than 114 ºC;

[0111] (3) The first resin is added to the reaction device of the second resin at a mass ratio of 1:1 with the second resin, stirred evenly, and then conveyed to the screw extrusion granulator by the feeder to granulate, so as to obtain a biodegradable in-situ nanocomposite material.

[0112] (4) 92% biodegradable polyester (polybutylene succinate and polycaprolactone in a mass ratio of 6:1) and 8% biodegradable in-situ nanocomposite material are continuously mixed and extruded in a screw extruder and biaxially stretched into a film to obtain a biodegradable film.

[0113] The composite film obtained through the above steps has a thickness of 50 μm. According to standard GB1040-2006 "Determination of Tensile Properties of Plastics", the tensile strength of the biodegradable polyester, tested by a universal testing machine, reaches 50 MPa, the elastic modulus reaches 50 MPa, and the elongation at break is approximately 600%. The tensile strength of the biodegradable film reaches 65 MPa, the elastic modulus reaches 68 MPa, and the elongation at break is approximately 750%.

[0114] Example 6

[0115] (1) Preparation of the first resin:

[0116] (1.1) 3.5 mol of lactide, 0.05 mol of ε-caprolactone, and 7% of the total monomer mass of alkaline lignin and lignin were mixed at a mass ratio of 2:1 to obtain a slurry. The slurry was transported to a reactor. At the same time, 0.0065 mol of stannous isooctanoate was transported from the catalyst pipeline. The reaction was carried out at a reaction temperature of 140 ºC and a reduced pressure of 100 Pa for 3 hours.

[0117] (1.2) After the polymerization reaction is completed, add 2.1% by mass of the polymerization product as a reaction aid (diphenyl diisocyanate is selected), stir evenly, and then feed it to a screw extruder for granulation to obtain the first resin; the density of the first resin is 1.24-1.27 g / cm³. 3 The number-average molecular weight is 7800-8900 kDa;

[0118] (2) Preparation of the second resin:

[0119] (2.1) 3.5 mol of lactide was delivered into the reactor, and at the same time, 0.007 mol of stannous chloride was delivered from the catalyst line; the reaction was carried out for 6 hours at a reaction temperature of 170 ºC and a pressure of 100 Pa.

[0120] (2.2) After the polymerization reaction is completed, add 1.8% (by mass of the polymerization product) of a reaction auxiliary agent (aziridine) to the polymerization product, and stir until homogeneous to obtain a second resin; the density of the second resin is 1.24-1.27 g / cm³. 3 The number-average molecular weight is 21,800-22,900 kDa;

[0121] (3) The first resin is added to the reaction device of the second resin at a mass ratio of 1:10 with the second resin, stirred evenly, and conveyed to the screw extruder through the feeder for continuous mixing and extrusion to obtain a biodegradable in-situ nanocomposite material.

[0122] (4) 95.5% biodegradable polyester (polylactic acid and polypropylene carbonate in a mass ratio of 5:1) and 4.5% biodegradable in-situ nanocomposite material are continuously mixed and extruded in a screw extruder and hot-pressed into a film to obtain a biodegradable film.

[0123] The composite film obtained through the above steps has a thickness of 200 μm. According to standard GB1040-2006 "Determination of Tensile Properties of Plastics", the tensile strength of the biodegradable polyester, tested by a universal testing machine, reaches 60 MPa, the elastic modulus reaches 2000 MPa, and the elongation at break is about 5%. The tensile strength of the biodegradable film can reach 70 MPa, the elastic modulus can reach 2500 MPa, and the elongation at break is about 30%.

[0124] Example 7

[0125] (1) Preparation of the first resin:

[0126] (1.1) 3.0 mol of ε-caprolactone, 0.1 mol of lactide, 3.5% of lignin by mass of the total monomer mass, and halloysite with an aspect ratio of 150 were mixed at a mass ratio of 3:1 to obtain a slurry. The slurry was transported to a reactor. At the same time, 0.0045 mol of zinc acetate was transported from the catalyst pipeline. The reaction was carried out at a reaction temperature of 135 ºC and a reduced pressure of 100 Pa for 2.5 hours.

[0127] (1.2) After the polymerization reaction is completed, 2.1% by mass of a reaction auxiliary agent (using diphenylmethane diisocyanate and aziridine in a mass ratio of 1:2) is added to the polymerization product. After stirring evenly, the mixture is fed to a screw extruder granulator for granulation to obtain the first resin; the density of the first resin is 1.24-1.27 g / cm³. 3 The number-average molecular weight is 4800-5900 kDa;

[0128] (2) Preparation of the second resin:

[0129] (2.1) 3.0 mol of ε-caprolactone and 0.2 mol of lactide were mixed to obtain a slurry, which was then transported to the reactor. At the same time, 0.0045 mol of aluminum chloride was transported from the catalyst pipeline. The reaction was carried out for 5.5 hours at a reaction temperature of 150ºC and a pressure of 100 Pa.

[0130] (2.2) After the polymerization reaction is completed, add 2.1% by mass of a reaction auxiliary agent (using a aziridine to propylene oxide mass ratio of 1:1) to the polymerization product, stir evenly, and then feed it to a screw extruder granulator for granulation to obtain the second resin; the density of the second resin is 1.24-1.27 g / cm³. 3 The number-average molecular weight is 10,500-14,500 kDa;

[0131] (3) The first resin and the second resin are continuously mixed and extruded in a screw extruder at a mass ratio of 4:1, and then conveyed to a screw extrusion granulator by a feeder to granulate, so as to obtain a biodegradable in-situ nanocomposite material.

[0132] (4) A biodegradable film is obtained by multi-layer co-extrusion of 91.5% biodegradable polyester (polycaprolactone and polysuccinic acid / ethylene terephthalate in a mass ratio of 2:1) and 8.5% biodegradable in-situ nanocomposite material.

[0133] The composite film obtained through the above steps has a thickness of 60 μm. According to standard GB1040-2006 "Determination of Tensile Properties of Plastics", the tensile strength of the biodegradable polyester, tested by a universal testing machine, reaches 15 MPa, the elastic modulus reaches 300 MPa, and the elongation at break is approximately 650%. The tensile strength of the biodegradable film can reach 20 MPa, the elastic modulus can reach 400 MPa, and the elongation at break is approximately 850%.

[0134] Example 8

[0135] (1) Preparation of the first resin:

[0136] (1.1) A slurry was prepared by mixing 1.00 mol of terephthalic acid, 1.5 mol of adipic acid, 3.0 mol of 1,4-butanediol, 0.5 mol of glycerol, and 0.2 mol of pentaerythritol, along with cellulose nanocrystals with an aspect ratio of 50 and halloysite with an aspect ratio of 150, comprising 8.4% of the total mass of aliphatic diols, aliphatic polyols, and dicarboxylic acids, at a mass ratio of 2:3. The slurry was then transported to a raw material storage tank at 70 °C. The slurry in the raw material storage tank was continuously transported to the esterification reactor through a raw material delivery pipeline. Simultaneously, 0.0105 mol of tetrabutyl titanate was transported from the catalyst pipeline at 75 °C. The internal reaction temperature of the esterification reactor was 210 °C. Under a nitrogen atmosphere at ambient pressure and normal pressure, the esterification water, byproducts, and remaining polymerized monomer mixture were collected through pipelines into the distillation column container, and the system was kept stable. When the esterification rate reached more than 90%, the pressure was reduced to 100 Pa, the temperature was increased to 245 °C, and the reaction continued for 2.5 hours.

[0137] (1.2) After the melt polycondensation is completed, a reaction aid (aziridine) of 2.5% by mass of the melt polycondensation product is added to the melt polycondensation product. After stirring evenly, the mixture is fed to a screw extruder granulator for granulation to obtain the first resin; the density of the first resin is 1.24-1.27 g / cm³. 3 The number-average molecular weight is 6800-7600 kDa, and the melting point is not less than 114 ºC;

[0138] (2) Preparation of the second resin:

[0139] (2.1) 2.50 mol of succinic acid, 3.0 mol of 1,4-butanediol and 0.2 mol of pentaerythritol were mixed to obtain a slurry. The slurry was transported to the raw material storage tank at 70 °C. The slurry in the raw material storage tank was continuously transported to the esterification reactor through the raw material delivery pipeline. At the same time, a solution containing 0.012 mol of tetrabutyl titanate at 75 °C was transported from the catalyst pipeline. The reaction temperature inside the esterification reactor was 218 °C and the atmosphere was atmospheric nitrogen. Esterification water, by-products and the remaining polymer monomer mixture were collected in the distillation column container through the pipeline and the system was kept stable. When the esterification rate reached more than 90%, the pressure was reduced to 100 Pa and the temperature was increased to 265 °C. The reaction continued for 3.5 hours.

[0140] (2.2) After the melt polycondensation is completed, a reaction aid (aziridine) of 3.8% by mass of the melt polycondensation product is added to the product. After stirring evenly, the mixture is fed to a screw extruder for granulation to obtain the second resin. The density of the second resin is 1.24-1.27 g / cm³. 3 The number-average molecular weight is 19,500-22,500 kDa, and the melting point is not less than 114 ºC;

[0141] (3) The first resin and the second resin are continuously mixed and extruded in a screw extruder at a mass ratio of 8:92, and then conveyed to a screw extrusion granulator for granulation through a feeder to obtain a biodegradable in-situ nanocomposite material.

[0142] (4) 97% biodegradable polyester (poly(dibutyl terephthalate) and polycaprolactone in a mass ratio of 3:1) and 3% biodegradable in-situ nanocomposite material are continuously mixed and extruded in a screw extruder and then injection molded to obtain a biodegradable film.

[0143] The composite film obtained through the above steps has a thickness of 2000 μm. According to standard GB1040-2006 "Determination of Tensile Properties of Plastics", the tensile strength of the biodegradable polyester, tested by a universal testing machine, reaches 38 MPa, the elastic modulus reaches 73 MPa, and the elongation at break is approximately 600%. The tensile strength of the biodegradable film reaches 50 MPa, the elastic modulus reaches 85 MPa, and the elongation at break is approximately 870%.

[0144] Example 9

[0145] (1) Preparation of the first resin:

[0146] (1.1) 3.0 mol glycolic acid, 0.1 mol lactide, and halloysite with an aspect ratio of 150 at a mass fraction of 1.7% of the total monomer mass were mixed to obtain a slurry. The slurry was transported to a reactor. At the same time, 0.0045 mol ethylsiloxane was transported from the catalyst line. The reaction was carried out at a reaction temperature of 135 ºC and a pressure reduction of 100 Pa for 2.5 hours.

[0147] (1.2) After the polymerization reaction is completed, add 1.7% (by mass) of a reaction aid (diphenylmethane diisocyanate) to the polymerization product, stir evenly, and then feed it to a screw extruder for granulation to obtain the first resin; the density of the first resin is 1.24-1.27 g / cm³. 3 The number-average molecular weight is 4800-5900 kDa;

[0148] (2) Preparation of the second resin:

[0149] (2.1) 3.0 mol of ε-caprolactone and 0.2 mol of glycolic acid were mixed to obtain a slurry, which was then transported to the reactor. Simultaneously, 0.0015 mol of aluminum chloride was transported from the catalyst line. The reaction was carried out for 5 hours at an internal reactor temperature of 150 ºC and a reduced pressure of 100 Pa.

[0150] (2.2) After the polymerization reaction is completed, add 2.1% (by mass of the polymerization product) of a reaction aid (propylene oxide), stir evenly, and then feed the mixture to a screw extruder for granulation to obtain a second resin; the density of the second resin is 1.24-1.27 g / cm³. 3 The number-average molecular weight is 10,500-14,500 kDa;

[0151] (3) The first resin and the second resin are continuously mixed and extruded in a screw extruder at a mass ratio of 1:3, and then conveyed to a screw extrusion granulator by a feeder to granulate, so as to obtain a biodegradable in-situ nanocomposite material.

[0152] (4) A biodegradable thin film is obtained by laminating a biodegradable polyester (polyglycolic acid and polysuccinic acid / ethylene terephthalate in a mass ratio of 1:4) with a mass fraction of 93.1% and a biodegradable in-situ nanocomposite material with a mass fraction of 6.9%.

[0153] The composite film obtained through the above steps has a thickness of 60 μm. According to standard GB1040-2006 "Determination of Tensile Properties of Plastics", the tensile strength of the biodegradable polyester, tested by a universal testing machine, reaches 15 MPa, the elastic modulus reaches 300 MPa, and the elongation at break is approximately 410%. The tensile strength of the biodegradable film can reach 20 MPa, the elastic modulus can reach 400 MPa, and the elongation at break is approximately 500%.

[0154] Unless otherwise specified, the raw materials and equipment used in this invention are all commonly used in the field; unless otherwise specified, the methods used in this invention are all conventional methods in the field.

[0155] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, alterations, and equivalent transformations made to the above embodiments based on the technical essence of the present invention shall still fall within the protection scope of the present invention.

Claims

1. The application of biodegradable in-situ nanocomposite materials in biodegradable materials, characterized in that, The biodegradable in-situ nanocomposite material comprises a first resin and a second resin; the first resin comprises 0.1-15% by mass of nanofiller and 85-99.9% by mass of resin with a number-average molecular weight of 500-10,000 kDa; the second resin comprises resin with a number-average molecular weight of 10,000-100,000 kDa; the monomers of the first and second resins are both aliphatic diols, aliphatic polyols, and diacids, or both are lactones and / or lactones; the application includes the following steps: The biodegradable material is prepared by mixing nanocomposite materials with biodegradable polyester at a mass ratio of 1-10:1-100 and then processing them.

2. The application as described in claim 1, characterized in that, The preparation process of the first resin is as follows: Option A: Aliphatic diols, aliphatic polyols, diacids, and nanofillers are subjected to in-situ melt polycondensation at 150 ºC-280 ºC to obtain a melt polycondensation product; reaction aids are added to the melt polycondensation product, and after mixing evenly, the first resin is obtained. Option B: In-situ polymerization of lactones and / or lactones and nanofillers is carried out at 80 ºC-180 ºC to obtain the polymerization product; reaction aids are added to the polymerization product and mixed evenly to obtain the first resin.

3. The application as described in claim 2, characterized in that: In Scheme A, the preparation process of the second resin is as follows: aliphatic diol, aliphatic polyol, and diacid are subjected to melt polycondensation at 150 ºC-280 ºC to obtain a melt polycondensation product; a reaction aid is added to the melt polycondensation product, and after mixing evenly, the second resin is obtained. In Scheme B, the preparation process of the second resin is as follows: the lactone and / or lactone are polymerized at 80 ºC-180 ºC to obtain the polymer product; a reaction aid is added to the polymer product, and after mixing evenly, the second resin is obtained.

4. The application as described in claim 1, characterized in that, The mass ratio of the first resin to the second resin is 1-10:1-100.

5. The application as described in claim 1, characterized in that, The nanofiller is one or more of cellulose, lignin, and halloysite with an aspect ratio of 10-1000.

6. The application as described in claim 2 or 3, characterized in that: In the preparation process of the first resin of Scheme A and / or the preparation process of the second resin of Scheme A, the mass of the nanofiller is 0.1-15% of the total mass of the aliphatic diol, aliphatic polyol and diacid; and / or In the preparation process of the first resin of Scheme A and / or the preparation process of the second resin of Scheme A, a polycondensation reaction catalyst is added during the melt polycondensation process; and / or In the preparation of the first resin of Scheme A and / or the preparation of the second resin of Scheme A, the mass of the reaction aid is 0.1-5% of the mass of the melt polycondensation product; and / or In the preparation process of the first resin of Scheme A and / or the preparation process of the second resin of Scheme A, the aliphatic diol is C2-C6. 20 One or more of straight-chain or branched aliphatic diols; and / or In the preparation process of the first resin of Scheme A and / or the preparation process of the second resin of Scheme A, the aliphatic polyol is one or more of glycerol, trimethylolethane, pentaerythritol, xylitol, and sorbitol; and / or In the preparation process of the first resin of Scheme A and / or the preparation process of the second resin of Scheme A, the diacid is composed of an aliphatic diacid and an aromatic diacid; and / or In the preparation process of the first resin of Scheme A and / or the preparation process of the second resin of Scheme A, the reaction aid is one or more of aziridine, epoxy, isocyanate, titanate, and oxazoline.

7. The application as described in claim 2 or 3, characterized in that: In the preparation of the first resin of Scheme B and / or the preparation of the second resin of Scheme B, a polymerization catalyst is added during the polymerization process; and / or In the preparation of the first resin of Scheme B and / or the preparation of the second resin of Scheme B, the mass of the reaction auxiliary is 0.1-5% of the mass of the polymerization product; and / or In the preparation process of the first resin of Scheme B and / or the preparation process of the second resin of Scheme B, the lactone and / or lactide have 2 to 6 carbon atoms; and / or In the preparation of the first resin of Scheme B and / or the preparation of the second resin of Scheme B, the reaction aid is one or more of aziridine, epoxy resins, isocyanates, titanates, and oxazoline resins.

8. The application as described in claim 1, characterized in that, The preparation method of the biodegradable in-situ nanocomposite material includes the following steps: (1) Preparation of the first resin; (2) Preparation of the second resin; (3) Blending: The first resin and the second resin are blended in a screw extruder to obtain a biodegradable in-situ nanocomposite material; or the first resin is added to the second resin and blended to obtain a biodegradable in-situ nanocomposite material.

9. The application as described in claim 1, characterized in that: The biodegradable polyester is one or more of the following: polybutylene adipate / terephthalate, polylactic acid, polycaprolactone, polyglycolic acid, polypropylene carbonate, polybutylene succinate, polybutylene succinate, polyhydroxyalkanoate, polyethylene succinate, and poly(ethylene adipate / terephthalate); and / or The processing method is one of the following: blown film method, cast film method, solution casting method, spin coating method, calendering method, multilayer co-extrusion method, biaxial stretching method, lamination method; and / or The biodegradable material is one of the following: film, sheet, or plate.