阅读说明：本技术 一种具有抗菌性的生物基聚酯的制备方法 (Preparation method of antibacterial bio-based polyester ) 是由 胡宇苗 徐锦龙 王松林 张婉迎 徐伟成 于 2020-06-02 设计创作，主要内容包括：本发明涉及生物基聚酯技术领域,公开了一种具有抗菌性的生物基聚酯的制备方法,包括以下步骤：将2,5-呋喃二甲酸、二元醇、催化剂和热稳定剂混合,进行酯化反应；将2,5-呋喃二甲酸二甲酯、至少含两个羟基的氨基醇、催化剂和热稳定剂混合,进行酯交换反应；将酯化反应产物和酯交换反应产物混合,进行酯交换反应；将酯交换反应产物抽真空,进行一阶段缩聚反应；待无白色液体抽出时,进行二阶段缩聚反应,制得聚酯；将聚酯用六氟异丙醇溶解后,滴加金属盐溶液,进行络合反应；加入不良溶剂进行沉淀,过滤,将沉淀用蒸馏水洗净后,烘干,即获得具有抗菌性的生物基聚酯。本发明的制备方法制得的生物基聚酯具有较好的抑菌和杀菌能力。(The invention relates to the technical field of bio-based polyester, and discloses a preparation method of bio-based polyester with antibacterial property, which comprises the following steps: mixing 2, 5-furandicarboxylic acid, dihydric alcohol, a catalyst and a heat stabilizer for esterification reaction; mixing dimethyl 2, 5-furandicarboxylate, amino alcohol containing at least two hydroxyl groups, a catalyst and a heat stabilizer, and carrying out ester exchange reaction; mixing the esterification reaction product and the ester exchange reaction product to carry out ester exchange reaction; vacuumizing the ester exchange reaction product, and carrying out one-stage polycondensation reaction; when no white liquid is extracted, carrying out two-stage polycondensation reaction to prepare polyester; dissolving polyester with hexafluoroisopropanol, and then dropwise adding a metal salt solution to perform a complex reaction; adding poor solvent for precipitation, filtering, washing the precipitate with distilled water, and oven drying to obtain antibacterial bio-based polyester. The bio-based polyester prepared by the preparation method has better antibacterial and bactericidal capabilities.)

1. A preparation method of antibacterial bio-based polyester is characterized by comprising the following steps:

(1) mixing 2, 5-furandicarboxylic acid, dihydric alcohol, a catalyst and a heat stabilizer for esterification reaction;

(2) mixing dimethyl 2, 5-furandicarboxylate, amino alcohol containing at least two hydroxyl groups, a catalyst and a heat stabilizer, and carrying out ester exchange reaction;

(3) mixing the esterification reaction product in the step (1) and the ester exchange reaction product in the step (2) to perform ester exchange reaction;

(4) vacuumizing the transesterification reaction product prepared in the step (3) and carrying out a one-stage polycondensation reaction; when no white liquid is extracted, carrying out two-stage polycondensation reaction to prepare polyester;

(5) dissolving the polyester prepared in the step (4) by using hexafluoroisopropanol, and then dropwise adding a metal salt solution to perform a complex reaction;

(6) adding poor solvent for precipitation, filtering, washing the precipitate with distilled water, and oven drying to obtain antibacterial bio-based polyester.

2. The method for preparing bio-based polyester having antibacterial property according to claim 1, wherein:

in the step (1), the temperature of the esterification reaction is 190-; and/or

In the step (2), the temperature of the ester exchange reaction is 180-190 ℃, and the time is 1-5 h; and/or

In the step (3), the temperature of the ester exchange reaction is 180-190 ℃ and the time is 1-5 h.

3. The method for preparing bio-based polyester having antibacterial property according to claim 1, wherein:

in the step (4), the temperature of the one-stage polycondensation reaction is 210-; and/or

In the step (4), the temperature of the two-stage polycondensation reaction is 230-260 ℃, the pressure is less than 100Pa, and the time is 1-5 h.

4. The method for preparing bio-based polyester having antibacterial property according to claim 1, wherein:

in the step (1), the molar ratio of the 2, 5-furandicarboxylic acid to the dihydric alcohol is 1: 1.6-2; and/or

In the step (2), the molar ratio of the dimethyl 2, 5-furandicarboxylate to the amino alcohol containing at least two hydroxyl groups is 1: 1.6-2.

5. The method for preparing antibacterial bio-based polyester according to claim 1, wherein in the step (3), the molar ratio of the esterification reaction product in the step (1) to the transesterification reaction product in the step (2) is 1: 1-2.

6. The method for preparing bio-based polyester having antibacterial property according to claim 1, wherein:

in the step (1), the dihydric alcohol is one or more of ethylene glycol, 1, 3-propylene glycol, 1, 4-butanediol, 1, 5-pentanediol, 1, 6-hexanediol and 1, 4-cyclohexanedimethanol; and/or

In the step (2), the amino alcohol containing at least two hydroxyl groups is serinol.

7. The method for preparing antibacterial bio-based polyester according to claim 1, wherein the modified tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer is grafted to the polyester after the polyester is prepared in the step (4), and the method comprises the following steps: mixing polyester and the modified tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer according to the mass ratio of 1:0.001-0.003, and carrying out ester exchange reaction at the temperature of 180-190 ℃ for 2-3 h.

8. The method for preparing antibacterial bio-based polyester according to claim 7, wherein the modified tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer is prepared by the following steps:

(a) synthesizing: under the protection of inert gas, dropwise adding a mixed solution of methyl acrylate and ethanol into a mixed solution of tris (2-aminoethyl) amine and triethylene tetramine, wherein the molar ratio of the methyl acrylate to the tris (2-aminoethyl) amine to the triethylene tetramine is 2-2.5:1:0.6-0.8, reacting at the temperature of 20-25 ℃ for 2-3h, removing the ethanol, and reacting at the temperature of 150-160 ℃ and at the pressure of 0.2-0.5kPa for 3-4h to obtain a tris (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer;

(b) modification: dispersing the tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer prepared in the step (a) and glycidyl butyrate into alcohol, wherein the mass ratio of the tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer to the glycidyl butyrate is 1:0.2-0.5, and reacting for 2-3h at the temperature of 100-; then adding ether for precipitation, filtering, dissolving the precipitate into water, adding sodium hydroxide solution, and reacting for 1-2h at 60-70 ℃; then adding ether for precipitation, filtering, and drying the precipitate to obtain the modified tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer.

9. The method for preparing antibacterial bio-based polyester according to claim 1, wherein in the step (5), the temperature of the complexation reaction is 45-55 ℃ and the time is 2-4 h.

10. The method for preparing bio-based polyester having antibacterial property according to claim 1, wherein:

in the step (5), the metal salt is a sulfate containing one or more of gold ions, silver ions, mercury ions, zinc ions, copper ions and barium ions and/or a chloride containing one or more of gold ions, silver ions, mercury ions, zinc ions, copper ions and barium ions; and/or

In the step (6), the poor solvent is one or more of aliphatic alkane and strong polar solvent.

Technical Field

The invention relates to the technical field of bio-based polyester, in particular to a preparation method of bio-based polyester with antibacterial property.

Background

The bio-based polyester mainly refers to a polyester material obtained by polymerizing dibasic acid and dihydric alcohol which take bio-based monomers as sources. In recent years, due to the continuous shortage of petroleum resources, bio-based materials are receiving more and more attention, and bio-based polyester is one of the most important materials. Research in the field of bio-based polyesters has mainly focused on polylactic acid (PLA), Polyhydroxyalkanoate (PHA), polybutylene succinate (PBS), polyethylene furan dicarboxylate (PEF), and the like. Among them, polyethylene furandicarboxylate (PEF) and petroleum-based polyethylene terephthalate (PET) have similar structure and performance, and are expected to replace PET in some fields, such as fibers, films, bottle sheets and the like. Some fields (especially biomedical materials) have high requirements on the antibacterial performance of PEF. At present, the petroleum-based PET antibacterial modification mainly comprises four methods of surface grafting modification, blending modification, copolymerization modification and nano inorganic composite modification, but no report about the antibacterial modification of bio-based PEF exists. Considering the particularity of the chemical structure of PEF, conventional modification methods are not suitable for the antibacterial modification of PEF. Therefore, a suitable antimicrobial modification process is of great importance for PEF.

Chinese patent publication No. CN108219121A discloses a bio-based polyester material with high barrier property and a synthetic method thereof, which takes 2, 5-furandicarboxylic acid and dihydric alcohol as raw materials and synthesizes the polyfurandicarboxylic acid dihydric alcohol ester with good mechanical property, thermal property and barrier property through three steps of esterification reaction, polycondensation reaction and purification and refining. The polyfurandioctyl phthalate glycol ester can block microorganisms to a certain extent through excellent blocking performance, but the microorganisms are only physically blocked and cannot be killed, so that the antibacterial capability is limited, and when the polyester is made into fibers for the textile field, the high blocking performance of the polyester cannot enable the made fabrics to have high blocking performance because the fabrics are formed by interweaving the fibers.

Disclosure of Invention

In order to solve the technical problems, the invention provides a preparation method of antibacterial bio-based polyester. The bio-based polyester prepared by the method has bacteriostatic and bactericidal capabilities, so that the bio-based polyester has good antibacterial performance, and can keep good antibacterial performance even if being applied to the textile field.

The specific technical scheme of the invention is as follows:

a preparation method of bio-based polyester with antibacterial property comprises the following steps:

(1) mixing 2, 5-furandicarboxylic acid, dihydric alcohol, a catalyst and a heat stabilizer for esterification reaction;

(2) mixing dimethyl 2, 5-furandicarboxylate, amino alcohol containing at least two hydroxyl groups, a catalyst and a heat stabilizer, and carrying out ester exchange reaction;

(3) mixing the esterification reaction product in the step (1) and the ester exchange reaction product in the step (2) to perform ester exchange reaction;

(4) vacuumizing the transesterification reaction product prepared in the step (3) and carrying out a one-stage polycondensation reaction; when no white liquid is extracted, carrying out two-stage polycondensation reaction to prepare polyester;

(5) dissolving the polyester prepared in the step (4) by using hexafluoroisopropanol, and then dropwise adding a metal salt solution to perform a complex reaction;

(6) adding poor solvent for precipitation, filtering, washing the precipitate with distilled water, and oven drying to obtain antibacterial bio-based polyester.

According to the invention, amino alcohol is introduced into a polyfuran dicarboxylic acid diol ester molecular chain, and a nitrogen atom with lone pair electrons in the amino alcohol complexes metal ions, so that the metal ions can be combined with cell membranes with negative charges of bacteria and fungi, the cell membrane functions are damaged, the metal ions enter cells, the normal metabolism of the cells is interfered, and the cells are finally killed.

In step (2), dimethyl 2, 5-furandicarboxylate was used instead of 2, 5-furandicarboxylic acid, because: the carboxyl in the 2, 5-furan dicarboxylic acid and the carboxyl in the amino alcohol are subjected to esterification reaction and condensation reaction simultaneously, so that nitrogen atoms with lone pair electrons in free side chains are consumed, and although the nitrogen atoms in the generated amido bonds can also be complexed with metal ions, the nitrogen atoms are positioned in the main chain and have limited activity, so that the side reaction can influence the antibacterial performance of the bio-based polyester; and the reaction selectivity of the ester group in the dimethyl 2, 5-furandicarboxylate is higher, so that the side reaction can be better prevented. The method for preventing the side reaction does not need extra steps and reagents, has simple operation and low cost, and can adapt to industrial production.

Preferably, in the step (1), the temperature of the esterification reaction is 190-200 ℃ and the time is 1-5 h.

The esterification reaction temperature between 2, 5-furandicarboxylic acid and diol needs to be controlled within a suitable range because: 2, 5-furandicarboxylic acid is solid during esterification reaction, and the solubility of the 2, 5-furandicarboxylic acid in dihydric alcohol is very low, so that the esterification reaction is a solid-liquid reaction, the activation energy is relatively high, and therefore, if the temperature is too low, the relatively high energy barrier of the esterification reaction cannot be overcome, the reaction is incomplete, and the viscosity of the finally prepared bio-based polyester is too low; if the temperature is too high, decarboxylation reaction of the 2, 5-furandicarboxylic acid occurs, and impurities in the 2, 5-furandicarboxylic acid also undergo side reactions, so that the finally prepared bio-based polyester has poor color. The invention controls the esterification reaction temperature at 190-200 ℃, can ensure the complete esterification reaction and reduce side reactions, so that the finally prepared bio-based polyester has ideal viscosity and color.

Preferably, in the step (2), the temperature of the transesterification reaction is 180-190 ℃ and the time is 1-5 h.

The temperature of the transesterification reaction between dimethyl 2, 5-furandicarboxylate and aminoalcohol should be controlled within a suitable range because: if the temperature is too low, the ester exchange reaction cannot be fully carried out, which can cause that the content of nitrogen atoms of complex metal in the bio-based polyester is too low, so that the antibacterial property of the polyester is not ideal; if the temperature is too high, the ester group in the dimethyl 2, 5-furandicarboxylate and the amino group in the amino alcohol undergo side reaction, consuming free side chain amino group, which also results in undesirable antibacterial property of the bio-based polyester. The invention controls the temperature of the ester exchange reaction at 180-190 ℃, can ensure the full reaction and simultaneously prevent the occurrence of side reaction, so that the finally prepared bio-based polyester has better antibacterial property.

Preferably, in the step (3), the temperature of the transesterification reaction is 180-190 ℃ and the time is 1-5 h.

Preferably, in the step (4), the temperature of the one-stage polycondensation reaction is 210-230 ℃ and the pressure is less than 0.1 MPa.

Preferably, in the step (4), the temperature of the two-stage polycondensation reaction is 230-260 ℃, the pressure is less than 100Pa, and the time is 1-5 h.

Preferably, in the step (1), the molar ratio of the 2, 5-furandicarboxylic acid to the diol is 1: 1.6-2.

Preferably, in step (2), the molar ratio of the dimethyl 2, 5-furandicarboxylate to the amino alcohol containing at least two hydroxyl groups is 1: 1.6-2.

Preferably, in the step (3), the molar ratio of the esterification reaction product in the step (1) to the transesterification reaction product in the step (2) is 1: 1-2.

The amount of amino alcohol to be introduced is controlled within a suitable range because: if the introduction amount of the amino alcohol is too small, too few metal ions are complexed, so that the antibacterial capability of the bio-based polyester is poor; if the introduction amount of the amino alcohol is too large, the introduction of the amino alcohol can damage the regularity of a molecular chain of the polyfurandicarboxylic acid diol ester, and a C-C chain segment in the chain has larger flexibility, so that the glass transition temperature of the bio-based polyester is too low, and the requirement on heat resistance cannot be met. The invention can improve the antibacterial ability of the bio-based polyester and meet the requirement of the bio-based polyester on the heat resistance by controlling the molar ratio of the esterification reaction product in the step (1) to the ester exchange reaction product in the step (2) within the range of 1: 1-2.

Preferably, in the step (1), the diol is one or more of ethylene glycol, 1, 3-propanediol, 1, 4-butanediol, 1, 5-pentanediol, 1, 6-hexanediol, and 1, 4-cyclohexanedimethanol.

Preferably, in step (2), the amino alcohol containing at least two hydroxyl groups is serinol.

Preferably, in the step (4), after the polyester is prepared, the modified tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer is grafted to the polyester, and the specific steps are as follows: mixing polyester and the modified tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer according to the mass ratio of 1:0.001-0.003, and carrying out ester exchange reaction at the temperature of 180-190 ℃ for 2-3 h.

The modified tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer has two hydroxyl groups (two hydroxyl groups are not on the same carbon atom) at the positions close to the tail ends of the branched chains, and the copolymer can be grafted to polyester through ester exchange reaction with the polyester through the two hydroxyl groups.

The requirement of heat resistance of the bio-based polyester limits the introduction amount of amino alcohol, thereby limiting the improvement of the antibacterial property of the polyester. The grafted tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer has larger volume and polarity, and can limit the internal rotation of a main chain, so that the influence of the introduction of amino alcohol on the heat resistance of the bio-based polyester can be reduced. Meanwhile, the molecular chain of the tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer contains a large amount of imino and amino, and the antibacterial performance of the bio-based polyester can be further improved after the tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer is complexed with metal ions.

However, the use of the tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer in too large an amount can result in too high a viscosity of the polyester, affect the processability of the polyester and limit the application of the polyester, so that the viscosity requirement of the polyester can limit the improvement of the antibacterial property of the copolymer. By introducing amino alcohol into a polyester molecular chain and grafting a tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer on a side chain, the two methods are complementary to each other, and the antibacterial property of the bio-based polyester can be improved to a greater extent.

Preferably, the modified tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer is prepared by the following process:

(a) synthesizing: under the protection of inert gas, dropwise adding a mixed solution of methyl acrylate and ethanol into a mixed solution of tris (2-aminoethyl) amine and triethylene tetramine, wherein the molar ratio of the methyl acrylate to the tris (2-aminoethyl) amine to the triethylene tetramine is 2-2.5:1:0.6-0.8, reacting at the temperature of 20-25 ℃ for 2-3h, removing the ethanol, and reacting at the temperature of 150-160 ℃ and at the pressure of 0.2-0.5kPa for 3-4h to obtain a tris (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer;

(b) modification: dispersing the tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer prepared in the step (a) and glycidyl butyrate into alcohol, wherein the mass ratio of the tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer to the glycidyl butyrate is 1:0.2-0.5, and reacting for 2-3h at the temperature of 100-; then adding ether for precipitation, filtering, dissolving the precipitate into water, adding sodium hydroxide solution, and reacting for 1-2h at 60-70 ℃; then adding ether for precipitation, filtering, and drying the precipitate to obtain the modified tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer.

In the step (a), methyl acrylate is firstly subjected to addition reaction with tris (2-aminoethyl) amine and triethylene tetramine respectively, the main reaction is that a carbon-carbon double bond in the methyl acrylate is reacted with one amino group in the tris (2-aminoethyl) amine, the carbon-carbon double bond in the methyl acrylate is reacted with one amino group in the triethylene tetramine, and in addition, the carbon-carbon double bond in the methyl acrylate is also reacted with one imino group in part of the triethylene tetramine; then, through the reaction between amino and ester, the condensation polymerization is carried out between the addition reaction product and the three reactants to form the tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer.

Methyl acrylate, tri (2-aminoethyl) amine and triethylene tetramine are used as comonomers, wherein the tri (2-aminoethyl) amine can improve the branching degree of the copolymer, improve the crosslinking degree of a network formed by the copolymer and the bio-based polyester, better limit the internal rotation of a main chain and play a role in improving the heat resistance of the polyester; triethylene tetramine can provide more imino groups, so that the cross-linking points of copolyester and bio-based polyester are more, the heat resistance of the polyester is better improved, and meanwhile, more metal ion complexing sites can be provided, and the antibacterial capacity of the polyester is improved.

In the step (b), firstly, the glycidyl butyrate is grafted to a molecular chain of the copolymer through a ring-opening reaction between an epoxy group in the glycidyl butyrate and an imino group and a terminal amino group in the copolymer, and a hydroxyl group is formed in the process; then the grafted ester group undergoes hydrolysis reaction to form another hydroxyl group. The two hydroxyl groups can perform ester exchange reaction with the polyester to graft the copolymer onto the molecular chain of the polyester.

The grafting ratio of glycidyl butyrate needs to be controlled within a suitable range because: the glycidyl butyrate is grafted to connect the copolymer and the polyester, and the process consumes nitrogen atoms with lone pair electrons in free side chains in the copolymer, so that if the grafting rate is too high, the antibacterial property of the bio-based polyester is low; if the graft ratio is too low, the crosslinking points between the copolymer and the polyester are too small, and the improvement of the heat resistance of the copolymer to the polyester is impaired. The invention controls the grafting rate of the glycidol butyrate by controlling the dosage of the glycidol butyrate and the ring-opening reaction condition.

Preferably, in the step (5), the temperature of the complexation reaction is 45-55 ℃ and the time is 2-4 h.

Preferably, in the step (5), the metal salt is a sulfate containing one or more of gold ions, silver ions, mercury ions, zinc ions, copper ions and barium ions and/or a chloride containing one or more of gold ions, silver ions, mercury ions, zinc ions, copper ions and barium ions.

Preferably, in the step (6), the poor solvent is one or more of aliphatic alkane and strong polar solvent.

The aliphatic alkane includes petroleum ether, pentane, hexane, etc., and the strong polar solvent includes methanol, acetonitrile, etc.

Preferably, in the step (1) and the step (2), the catalyst comprises one or more of n-butyl titanate, isopropyl titanate, stannous octoate, stannous oxalate, dibutyltin oxide, lithium acetate, potassium acetate, calcium acetate, magnesium acetate, barium acetate, zinc acetate, cobalt acetate, antimony acetate, lead acetate, manganese acetate, a silicon dioxide/titanium dioxide compound, a silicon dioxide/titanium dioxide/nitrogen-containing compound and a silicon dioxide/phosphorus-containing compound.

Preferably, in the step (1) and the step (2), the heat stabilizer comprises one or more of an antioxidant 1010, an antioxidant 1076, an antioxidant 425, an antioxidant 330, an antioxidant 1178, an antioxidant 618, an antioxidant 626, an antioxidant 168, tetraphenyl dipropylene glycol diphosphite, trimethyl phosphite, triethyl phosphite, triisooctyl phosphite, triisodecyl phosphite, trilauryl phosphite, tris (tridecyl) phosphite, trioctadecyl phosphite, triphenyl phosphite, tri-p-tolyl phosphite, ditridecyl phosphite, tris (2, 4-di-tert-butyl) phosphite, pentaerythritol dioctadecyl phosphite, pentaerythritol diisodecyl phosphite, pentaerythritol diphosphotridecyl phosphite, pentaerythritol tetrapentaerythritol tetrapentaphenyl tridecyl phosphite, phosphoric acid, phosphorous acid, polyphosphoric acid and triethyl phosphonoacetate.

Compared with the prior art, the invention has the following advantages:

(1) through introducing amino alcohol into a molecular chain of the bio-based polyester and complexing metal ions by nitrogen atoms, the bio-based polyester can be endowed with bacteriostatic and bactericidal capabilities, so that the bio-based polyester has better antibacterial performance, and fibers and fabrics with excellent antibacterial performance can be obtained even if the bio-based polyester is applied to the textile field;

(2) the antibacterial property of the bio-based polyester can be further improved on the premise of meeting the requirements on heat resistance and viscosity by grafting the tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer on the molecular chain of the bio-based polyester and complexing metal ions by nitrogen atoms in imino and amino.

Detailed Description

The present invention will be further described with reference to the following examples.

General examples

Preparing a bio-based polyester by:

(1) mixing 2, 5-furandicarboxylic acid and dihydric alcohol according to a molar ratio of 1:1.6-2, adding a catalyst and a heat stabilizer, and carrying out an esterification reaction at 190-200 ℃ for 1-5 h; the dihydric alcohol is one or more of ethylene glycol, 1, 3-propylene glycol, 1, 4-butanediol, 1, 5-pentanediol, 1, 6-hexanediol, and 1, 4-cyclohexanedimethanol; the catalyst comprises one or more of n-butyl titanate, isopropyl titanate, stannous octoate, stannous oxalate, dibutyltin oxide, lithium acetate, potassium acetate, calcium acetate, magnesium acetate, barium acetate, zinc acetate, cobalt acetate, antimony acetate, lead acetate, manganese acetate, a silicon dioxide/titanium dioxide compound, a silicon dioxide/titanium dioxide/nitrogen-containing compound and a silicon dioxide/phosphorus-containing compound; the heat stabilizer comprises one or more of an antioxidant 1010, an antioxidant 1076, an antioxidant 425, an antioxidant 330, an antioxidant 1178, an antioxidant 618, an antioxidant 626, an antioxidant 168, tetraphenylpropylene glycol diphosphite, trimethyl phosphite, triethyl phosphite, triisooctyl phosphite, triisodecyl phosphite, trilauryl phosphite, tris (tridecyl) phosphite, trioctadecyl phosphite, triphenyl phosphite, tri-p-tolyl phosphite, ditridecyl phosphite, tris (2, 4-di-tert-butyl) phosphite, pentaerythritol dioctadecyl phosphite, pentaerythritol diisodecyl phosphite, pentaerythritol diphosphotridecyl phosphite, pentaerythritol tetrapentaerythritol tetrapentaphenyl tridecyl phosphite, phosphoric acid, phosphorous acid, polyphosphoric acid and triethyl phosphonoacetate;

(2) mixing dimethyl 2, 5-furandicarboxylate and amino alcohol containing at least two hydroxyl groups according to a molar ratio of 1:1.6-2, adding a catalyst and a heat stabilizer, and carrying out an ester exchange reaction at 180-190 ℃ for 1-5 h; the amino alcohol containing at least two hydroxyl groups is serinol; the catalyst comprises one or more of n-butyl titanate, isopropyl titanate, stannous octoate, stannous oxalate, dibutyltin oxide, lithium acetate, potassium acetate, calcium acetate, magnesium acetate, barium acetate, zinc acetate, cobalt acetate, antimony acetate, lead acetate, manganese acetate, a silicon dioxide/titanium dioxide compound, a silicon dioxide/titanium dioxide/nitrogen-containing compound and a silicon dioxide/phosphorus-containing compound; the heat stabilizer comprises one or more of an antioxidant 1010, an antioxidant 1076, an antioxidant 425, an antioxidant 330, an antioxidant 1178, an antioxidant 618, an antioxidant 626, an antioxidant 168, tetraphenylpropylene glycol diphosphite, trimethyl phosphite, triethyl phosphite, triisooctyl phosphite, triisodecyl phosphite, trilauryl phosphite, tris (tridecyl) phosphite, trioctadecyl phosphite, triphenyl phosphite, tri-p-tolyl phosphite, ditridecyl phosphite, tris (2, 4-di-tert-butyl) phosphite, pentaerythritol dioctadecyl phosphite, pentaerythritol diisodecyl phosphite, pentaerythritol diphosphotridecyl phosphite, pentaerythritol tetrapentaerythritol tetrapentaphenyl tridecyl phosphite, phosphoric acid, phosphorous acid, polyphosphoric acid and triethyl phosphonoacetate;

(3) mixing the esterification reaction product in the step (1) and the transesterification reaction product in the step (2) according to a molar ratio of 1:1-2, and carrying out transesterification reaction at 180-190 ℃ for 1-5 h;

(4) vacuumizing the transesterification reaction product prepared in the step (3) to a pressure of less than 0.1Mpa, and performing a one-stage polycondensation reaction at the temperature of 210 ℃ and 230 ℃; when no white liquid is extracted, vacuumizing to the pressure of less than 100Pa, and carrying out two-stage polycondensation reaction at the temperature of 230-260 ℃ for 1-5h to obtain polyester;

(5) dissolving the polyester prepared in the step (4) by using hexafluoroisopropanol, then dropwise adding a metal salt solution, and carrying out a complex reaction at 45-55 ℃ for 2-4 h; the metal salt is sulfate containing one or more of gold ion, silver ion, mercury ion, zinc ion, copper ion and barium ion and/or chloride containing one or more of gold ion, silver ion, mercury ion, zinc ion, copper ion and barium ion;

(6) adding a poor solvent for precipitation, filtering, washing the precipitate with distilled water, and drying to obtain the antibacterial bio-based polyester; the poor solvent is one or more of aliphatic alkane and strong polar solvent.

Optionally, in the step (4), after the polyester is prepared, the modified tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer is grafted to the polyester, and the specific steps are as follows:

(a) synthesizing: under the protection of inert gas, dropwise adding a mixed solution of methyl acrylate and ethanol into a mixed solution of tris (2-aminoethyl) amine and triethylene tetramine, wherein the molar ratio of the methyl acrylate to the tris (2-aminoethyl) amine to the triethylene tetramine is 2-2.5:1:0.6-0.8, reacting at the temperature of 20-25 ℃ for 2-3h, removing the ethanol, and reacting at the temperature of 150-160 ℃ and at the pressure of 0.2-0.5kPa for 3-4h to obtain a tris (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer;

(b) modification: dispersing the tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer prepared in the step (a) and glycidyl butyrate into alcohol, wherein the mass ratio of the tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer to the glycidyl butyrate is 1:0.2-0.5, and reacting for 2-3h at the temperature of 100-; then adding ether for precipitation, filtering, dissolving the precipitate into water, adding sodium hydroxide solution, and reacting for 1-2h at 60-70 ℃; then adding ether for precipitation, filtering, and drying the precipitate to obtain a modified tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer;

(c) grafting: mixing the polyester with the modified tri (2-aminoethyl) amine-methyl acrylate-triethylene tetramine copolymer prepared in the step (b) according to the mass ratio of 1:0.001-0.003, and carrying out ester exchange reaction at the temperature of 180-190 ℃ for 2-3 h.