Preparation and Application of a Degradable Bio-Copolyester and an Antiviral Copolyester Film

Abstract

The present invention discloses a biodegradable bio-copolyester, the preparation and application of an antiviral copolyester film, belonging to the field of preparation of antiviral materials. Neopentyl glycol, 1,4-cyclohexanedicarboxylic acid, 2,5-pyrimidinedicarboxylic acid and a catalyst are subjected to catalytic esterification and catalytic polycondensation reactions under nitrogen protection to obtain a crude copolyester. The biodegradable bio-copolyester is obtained through solvent extraction, precipitation with a precipitant, filtration and drying. The copolyester synthesized by the present invention has a high molecular weight, good mechanical properties and flexibility, and is easily degraded by the environment after being discarded. The copolyester material after loading Ag has good antiviral performance and can be used as a base material for medical devices, such as doctor's surgical gowns, surgical caps, surgical gloves, surgical sheets, and disposable antiviral sheets for wards and guest rooms.

Description

Technical Field

[0001] The present invention relates to the preparation and application of a degradable bio-copolyester and an antiviral copolyester film, belonging to the field of the preparation of antiviral materials. Specifically, neopentyl glycol, 1,4-cyclohexanedicarboxylic acid and 2,5-pyrimidinedicarboxylic acid are used as raw materials to synthesize a degradable bio-copolyester P through catalytic esterification and catalytic polycondensation reactions. The prepared degradable bio-copolyester P is made into a film, and the surface of the film is fully infiltrated with a self-made Ag2S-polyvinylpyrrolidone PVP sol to make an antiviral copolyester film, which is next used for preparing the substrate of antiviral medical devices. Background Art

[0002] Viruses are transmitted through various routes such as aerosols, fecal-oral, urine, conjunctiva, mother-to-child, etc. A large number of antiviral protective articles are used to isolate and protect the uninfected population and medical staff. In particular, when medical staff come into contact with the blood, clothes, body fluids, secretions and excretions of patients, they should wear medical protective articles for isolation and protection to prevent cross-infection and reduce the risk of infection. Medical protective articles include medical protective masks, disposable caps or cloth caps, work shoes and socks, work clothes, gloves, protective clothing or isolation gowns, disposable medical surgical masks, protective glasses, and shoe covers, etc. Research shows that textiles play a key role in the virus infection chain, and a large number of viruses are extracted from these medical protective articles, especially medical textile materials. Therefore, it is particularly important to study antiviral protective polyester textiles [1] ([1] Chen Nannan, Wang Jinmei, Tao Lizhen. Antiviral Protective Textiles [J]. Synthetic Fiber, 2020, 49(09): 32-35.). Taking the opportunity of fighting against the COVID-19 pandemic, the social demand for antiviral processing materials has skyrocketed to better protect the safety of ordinary consumers and reduce the risk of infection to maintain the overall cleanliness of the living space. Recently, the textile industry has invented a variety of new antiviral materials. Such technologies aim to prevent the formation of a hotbed for the spread of harmful viruses and bacteria on the fabric surface, thereby helping to reduce the risk and speed of pollution and transmission. Therefore, there is also a greater preference for daily consumer goods with antiviral functions [2] ([2] Hu Lizhu. Interpretation of the ISO 18184 Standard for the Determination of Antiviral Activity of Textiles [J]. Knitting Industry, 2021(01): 74-77.).

[0003] Due to the advantages of low cost, easy processing and molding, excellent mechanical properties, and good chemical stability of polymer materials, polymer materials have developed rapidly since the 20th century. Their products are widely used in various aspects such as clothing, automobiles, tableware, electronic products, and daily necessities, playing a very important role in human life. Polyester fiber is the chemical fiber variety with the largest consumption, accounting for 52.2% of the global textile fiber consumption. Polyester is an important material in the fields of synthetic fibers and plastics. In 2020, the output of polyester fiber in China has reached 49.8 million tons; about 3 million tons of polyester are used for packaging various beverages and liquid foods; in addition, there are also hundreds of thousands of tons of polyester film products. However, most polymer materials are either non-biodegradable or difficult to degrade. The white pollution caused by improper treatment is quite harmful to the environment. First of all, plastics are very difficult to degrade. Using C14 isotope to track and investigate the degradation of plastics in the soil, the results show that their degradation speed usually requires 200 - 400 years, and the deterioration of the soil environment will seriously affect the growth of crops; secondly, after plastic waste is swallowed by animals, it is easy to cause intestinal obstruction and death of animals; thirdly, plastic waste that is not easily recycled is scattered on streets, rural power grids, railways, etc., causing visual pollution; fourthly, the harmful gases such as dioxins and H2S generated by the incineration treatment of waste plastics will seriously pollute the atmosphere, release a large amount of toxic gases, generate a large amount of dust and smoke, cause smog, and affect human health [3] ([3] Wang Qi, Qu Jinping, Shi Bi, Chen Ning, Nie Min, Yang Shuangqiao. Research on the Prevention and Control Strategy of Waste Plastic Pollution in China [J]. Engineering Sciences in China, 2021, 23(1): 160 - 166.)

[0004] With the continuous enhancement of people's environmental protection awareness, while the material achieves effective antiviral properties, it is also necessary to reduce the pollution of its waste to the environment. Therefore, the preparation of copolyester materials with both antiviral and degradable properties will become a research hotspot. Antiviral materials based on bio-based polyesters integrate the advantages of various materials, have antiviral characteristics and good mechanical toughness, and will be an important direction for future development

[0005] Based on the above background, the diol and diacid raw materials used in the present invention can be obtained from biomass or biomass derivatives. A degradable bio-copolyester based on neopentyl glycol is synthesized by catalytic melt polycondensation. The prepared degradable bio-copolyester P is made into a film, and the film is fully infiltrated on its surface by a self-made Ag2S - polyvinylpyrrolidone PVP sol. It can be used as the substrate for preparing antiviral medical devices, has high safety performance for the human body, good mechanical properties and flexibility, has good antiviral characteristics, and is easily degraded by the environment after being discarded Summary of the Invention

[0006] In view of the above problems existing in the prior art, the present invention uses biomass neopentyl glycol as the alcohol source, 1,4-cyclohexanedicarboxylic acid and 2,5-pyrimidinedicarboxylic acid as the first acid source and the second acid source respectively, and synthesizes a degradable bio-copolyester through catalytic esterification and catalytic polycondensation reactions. The prepared degradable bio-copolyester P is made into a film, and the film is fully infiltrated on its surface by a self-made Ag2S-polyvinylpyrrolidone PVP sol, and can be used as a substrate for preparing antiviral medical devices. It has high safety performance for the human body. Its mechanical properties and flexibility are good. The characteristics of light weight and good toughness make the film made of it suitable for the medical protection field. Combined with its unique good antiviral characteristics, it is particularly suitable for the preparation of medical protection articles, including medical protective masks, medical gloves, medical protective clothing or isolation gowns, protective caps and protective shoe covers, etc. It is easily degraded by the environment after being discarded after use.

[0007] To achieve the purpose of the present invention, the following technical solutions are adopted in the present invention:

[0008] To better implement the technical solution of the present invention, the present invention discloses a preparation and application of a degradable bio-copolyester and an antiviral copolyester film, and a preparation method of the copolyester and the antiviral copolyester film, including the following steps:

[0009] 1. A degradable bio-copolyester P, characterized in that it has a structure shown in Formula 1:

[0010]

[0011] Formula 1

[0012] Wherein: x in Formula 1 is 108-137, and y is 110-138.

[0013] 2. The preparation of a degradable bio-copolyester P, characterized in that the preparation method includes the following steps:

[0014] 1) Synthesis of the copolyester crude product: Neopentyl glycol with a CAS number of 126-30-7 is used as the alcohol source, 1,4-cyclohexanedicarboxylic acid with a CAS number of 1076-97-7 is used as the first acid source, and 2,5-pyrimidinedicarboxylic acid with a CAS number of 127527-24-6 is used as the second acid source. They are added to the reaction vessel according to the molar ratio of alcohol source: first acid source: second acid source = 10: (5-5.7): (3.5-4.2). An appropriate amount of catalyst monobutyltin oxide is added, nitrogen is introduced for protection, and the reaction is stirred at 150-180 °C for 2-4 h to obtain an esterification product. The esterification product is further heated to 220-240 °C, and the absolute pressure in the reaction system is controlled at 90-140 Pa. The polycondensation reaction is carried out with sufficient stirring for 2-4 h to obtain the copolyester crude product;

[0015] 2) Purification of crude copolyester: The crude copolyester is dissolved in chloroform, filtered, and the supernatant is taken. An appropriate amount of low-carbon alcohol is added to the supernatant until the precipitate no longer increases. The solution is centrifuged and filtered. The resulting solid is washed with ethanol and filtered. The filtered solid is dried at 60-70°C for 1-2 hours to obtain a biodegradable biocopolyester P.

[0016] 3) In step 1), the appropriate amount of catalyst monobutyltin oxide is 0.05% to 0.15% of the amount of neopentyl glycol.

[0017] 4) The low-carbon alcohol in step 2) is one of methanol, ethanol and isopropanol.

[0018] 3. Preparation and application of antiviral copolyester film. The obtained biodegradable copolyester P can be used to prepare the substrate of antiviral medical equipment in the next step. The preparation method includes the following steps:

[0019] 1) Preparation of copolyester film: Weigh 100 parts by weight of biodegradable biocopolyester P, mix uniformly with 1 part by weight of chain extender epoxy compound ADR-4368-C, 1 part by weight of antioxidant 3114, 0.5 part by weight of antioxidant 168, and 1-5 parts by weight of liquid paraffin, extrude using a twin-screw extruder, and pelletize. Then, mix uniformly with 10 parts by weight of toughening agent PEG, and blow mold to obtain a dry and clean copolyester film.

[0020] 2) Preparation of Ag2S-polyvinylpyrrolidone (PVP) sol: Step 1: Prepare a dispersant solution R by weighing 10 parts by mass of PVP with a molecular weight of 8900 g / mol, adding 190 parts by mass of an ethanol aqueous solution with a volume concentration of 50%, and stirring thoroughly to obtain 200 parts by mass of dispersant solution R; Step 2: Take 140 parts by mass of dispersant solution R, add sodium thiosulfate, and prepare a Na2S2O3 solution with a concentration of 2.0-2.5 g / L; Take another 60 parts by mass of dispersant solution R and prepare an AgNO3 solution with a concentration of 2.0-2.5 g / L; Slowly add the AgNO3 solution prepared in the second step to the Na2S2O3 solution prepared in the first step, and after the addition is complete, stir in the dark for 2-4 hours to obtain an Ag2S-polyvinylpyrrolidone (PVP) sol;

[0021] 3) Preparation and application of antiviral copolyester film: Fix one end of the prepared dry and clean copolyester film, and slowly immerse the other end in Ag2S-polyvinyl pyrrolidone PVP sol to fully wet its surface with Ag2S-polyvinyl pyrrolidone PVP sol to reach adsorption equilibrium. Then slowly pull out the copolyester film and dry it to obtain a uniform and dense antiviral copolyester film, which can be processed into medical substrates, such as doctor's surgical gowns, surgical caps, surgical gloves, surgical sheets and disposable antiviral sheets used in wards and guest rooms.

[0022] Beneficial effects:

[0023] 1. Careful selection of raw materials: In this experiment, neopentyl glycol, 1,4-cyclohexanedicarboxylic acid, and 2,5-pyrimidinedicarboxylic acid were used as raw materials to prepare copolyesters, replacing petroleum-based monomers as the basic raw materials for preparing copolyesters, which is conducive to the implementation of the national policies of carbon emission reduction and carbon neutrality, and the environmental protection characteristics of the products are remarkable.

[0024] 2. Yang Xiongnan [4] ([4] Yang Xiongnan, Zhang Xiaolin, Duan Jingting, Xu Long, Li Shaoge, Zhuo Guangming. Effects of several fillers on the properties of jute fiber / polypropylene composites [J]. New Chemical Materials, 2022, 50(06): 209-214.) reported that the flexural strength of a polypropylene composite was 38.6 MPa, the tensile strength was 28.5 MPa, and the elongation at break was 211.4%. The number-average molecular weight of a biodegradable bio-copolyester P prepared in the present invention is 3.00×10 4 ~3.80×10 4 g / mol, the flexural strength is 95.0~120.0 MPa, the tensile strength is 70.0~95.0 MPa, and the elongation at break is 265.0%~300.0%, which greatly enhances the tensile ability of the copolyester, makes the copolyester prepared in the present invention have high ductility, and is more easily stretched into a tensile-resistant film with performance meeting the use requirements. In the next step, it can be processed into a medical substrate. The characteristics of light weight and good toughness make the film made of it very suitable for the use requirements of light weight and good toughness required in the medical protection field.

[0025] 3. Zheng Youdan [5] ([5] Zheng Youdan. Preparation and properties of antiviral polyamide 6 FDY [J]. China Textile Leader, 2021(04): 47-50.) reported the preparation and properties of an antiviral polyamide. Its antiviral activity rate is 96.67%. The antiviral copolyester film prepared in the present invention has excellent antiviral effects. As the content of Ag2S in the copolyester film increases, the antiviral infection effect becomes more obvious. When the mass fraction of Ag2S reaches 1.2%, the antiviral activity rate against influenza A virus H1N1 is 99.37%, and the antiviral activity rate against influenza A virus H3N2 is 98.63%. The characteristics of light weight and good toughness make the film made of it suitable for the medical protection field, and combined with its unique good antiviral characteristics, it is especially suitable for the preparation of medical protection products, including medical protective masks, medical gloves, medical protective clothing or isolation gowns, protective caps, and protective shoe covers, etc.

[0026] 4. Zhang Lifei [6]([6] Zhang Lifei, Liu Junwang, Ma Chengguo, Wang Yongliang, Han Zhidong. Thermal Degradation Process and Combustion Behavior of Magnesium Hydroxide / Expandable Graphite / Polypropylene Composites [J]. Journal of South China Normal University (Natural Science Edition), 2020, 52(01): 17-22.) reported that the degradation of a polypropylene composite material needs to be carried out at a high temperature of 290-450 °C. The antiviral and biodegradable bio-copolyester film based on neopentyl glycol prepared in the present invention has good biodegradability. After being discarded and buried in the soil of the natural environment, it degrades by 5% in the first year, 10% in the second year, and more than 18% in the third year, and is harmless to the environment after degradation. Detailed implementation manners

[0027] The present invention will be further described below through examples, but the present invention is not limited by the examples. The raw material substances in the present invention are all commercially available.

[0028] The polyesters prepared in the examples were all characterized by 1H NMR using a Bruker Avance DMX600 nuclear magnetic resonance spectrometer 1 with TMS as the internal standard and CDCl3 as the solvent.

[0029] Mechanical property tests in the examples: The tensile property test was carried out according to the standard of GB / T 1040.2-2006; the bending property was carried out according to the standard of GB / T 9341-2008;

[0030] The results were each the average value of 5 test specimens.

[0031] Yield = 100% × actual production amount of target product / theoretical production amount of target product.

[0032] Antiviral functional test of the co-polyester film: According to ISO 18184-2019, after the sample was hot-pressed into a rectangular sheet of 60 mm × 60 mm, the plaque assay method was used to measure the virus titer, and the antiviral activity value M was obtained v [7] ([7] Hu Lizhu. Interpretation of the ISO 18184 Standard for Determining Antiviral Activity of Textiles [J]. Knitting Industry, 2021(01): 74-77.).

[0033] Example 1: 3.749 g (0.036 mol) of neopentyl glycol, 3.099 g (0.018 mol) of 1,4-cyclohexanedicarboxylic acid, 2.185 g (0.013 mol) of 2,5-pyrimidinedicarboxylic acid and 0.069 g of monobutyltin oxide were successively added to a 50 ml single-necked flask. Nitrogen was introduced for protection, and the reaction was stirred at 160 °C under atmospheric pressure for 4 h to obtain an esterification product. The esterification product was further heated to 230 °C, and the absolute pressure in the reaction system was controlled at about 100 Pa, and the reaction was carried out for 3 h to obtain a crude polycondensation product. A sufficient amount of chloroform was added to the crude polyester, and after shaking to promote dissolution, it was soaked for 2 h, centrifuged and precipitated, and filtered; the clear liquid was added dropwise to 50 ml of methanol to obtain a turbid liquid and a precipitate was formed until the precipitate no longer increased. It was centrifuged and separated again, filtered to obtain a solid, and the obtained solid was washed with cold ethanol, and the solid after filtration was dried at 70 °C for 2 h to obtain the required environmentally friendly copolyester P1: 7.522 g, and the yield was 90.36%. After testing, the number-average molecular weight was 3.22×10 4 g / mol, the flexural strength was 96.2 MPa, the tensile strength was 70.3 MPa, and the elongation at break was 265.7%.

[0034] Preparation of antiviral copolyester film: Collect 100 g of copolyester P1, mix it evenly with 1 g of chain extender epoxide ADR-4368-C, 1.0 g of antioxidant 3114, 0.5 g of antioxidant 168, and 10 ml of liquid paraffin, and cut it into pellets after stirring and extruding with a twin-screw extruder; Through the blow molding process, a copolyester film is obtained; Weigh 10 g of polyvinylpyrrolidone PVP, add a sufficient volume of ethanol aqueous solution with a concentration of 50%, and stir well to obtain 200 g of dispersant solution R; Take 140 g of dispersant solution R, add sodium thiosulfate to prepare a Na2S2O3 solution with a concentration of 1.7 g / L; Take another 60 g of dispersant solution R and prepare an AgNO3 solution with a concentration of 1.7 g / L; Slowly drip the AgNO3 solution into the Na2S2O3 solution. After dripping, stir in the dark for 4 hours to obtain an Ag2S-polyvinylpyrrolidone PVP sol; Fix one end of the prepared copolyester film, and slowly immerse the other end into the above-mentioned Ag2S-polyvinylpyrrolidone PVP sol to make its surface infiltrate with the Ag2S-polyvinylpyrrolidone PVP sol, reach the adsorption equilibrium, then slowly pull it out, and dry it to obtain a uniform and dense antiviral copolyester film. Take 0.6 ml of artificially cultured diluted virus solutions H1N1 and H3N2 respectively, and drop them on the surface of 60 mm×60 mm square pieces of antiviral copolyester P1 film with the mass fraction of antiviral diluent Ag2S being 0.2%, 0.4%, 0.8%, and 1.2% respectively. Then pick up the polyethylene covering film with virus-killing forceps and lay it flat on the surface of each square piece to ensure that the diluted virus solution is in full and uniform contact with the surface of the square piece. Place it in a petri dish and put it in a 37°C constant temperature incubator for 24 h, and measure the virus data every eight hours.

[0035] The antiviral copolyester film material P1, with the surface antiviral performance index value M v is 3.18, meeting the conditions for sufficient antiviral effect. It is an antiviral material with good performance and can be further used as the base material for medical protective equipment, such as making surgical gowns and surgical caps, so that the surgical gowns and surgical caps have good antiviral effects.

[0036] Example 2: 3.749 g (0.036 mol) of neopentyl glycol, 3.444 g (0.020 mol) of 1,4-cyclohexanedicarboxylic acid, 2.185 g (0.013 mol) of 2,5-pyrimidinedicarboxylic acid and 0.069 g of monobutyltin oxide were successively added to a 50 ml single-necked flask. Nitrogen was introduced for protection, and the reaction was stirred at 160 °C under atmospheric pressure for 4 h to obtain an esterification product. The esterification product was further heated to 230 °C, and the absolute pressure in the reaction system was controlled at about 100 Pa, and the reaction was carried out for 3 h to obtain a crude polycondensation product. Sufficient chloroform was added to the crude polyester, and after shaking to promote dissolution, it was soaked for 2 h, centrifuged and precipitated, and filtered; the clear liquid was added dropwise to 50 ml of methanol to obtain a turbid liquid and a precipitate was formed until the precipitate no longer increased. It was centrifuged and separated again, filtered to obtain a solid, and the obtained solid was washed with cold ethanol, and the solid after filtration again was dried at 70 °C for 2 h to obtain the required environmentally friendly copolyester P2: 8.173 g, with a yield of 92.15%. After testing, the number-average molecular weight was 3.48×10 4 g / mol, the flexural strength was 104.6 MPa, the tensile strength was 78.5 MPa, and the elongation at break was 279.2%.

[0037] Preparation of antiviral copolyester film: Collect 100 g of copolyester P2, mix it evenly with 1 g of chain extender epoxide ADR-4368-C, 1.0 g of antioxidant 3114, 0.5 g of antioxidant 168, and 10 ml of liquid paraffin, stir and extrude it with a twin-screw extruder, and then pelletize it; through the blow molding process, obtain the copolyester film; weigh 10 g of polyvinylpyrrolidone PVP, add a sufficient volume of ethanol aqueous solution with a concentration of 50%, and stir well to obtain 200 g of dispersant solution R; take 140 g of dispersant solution R, add sodium thiosulfate to prepare a Na2S2O3 solution with a concentration of 1.7 g / L; take another 60 g of dispersant solution R and prepare an AgNO3 solution with a concentration of 1.7 g / L; slowly drip the AgNO3 solution into the Na2S2O3 solution, after dripping, stir in the dark for 4 hours to obtain Ag2S-polyvinylpyrrolidone PVP sol; fix one end of the prepared copolyester film, slowly immerse the other end into the above Ag2S-polyvinylpyrrolidone PVP sol to make its surface infiltrate with Ag2S-polyvinylpyrrolidone PVP sol, reach the adsorption equilibrium, then slowly pull it out, and dry it to obtain a uniform and dense antiviral copolyester film. Respectively take 0.6 ml of artificially cultured diluted virus solutions H1N1 and H3N2, and drop them on the surfaces of 60 mm×60 mm square pieces of antiviral copolyester P2 film with the mass fractions of Ag2S in the antiviral diluent being 0.2%, 0.4%, 0.8%, and 1.2% respectively, then pick up the polyethylene covering film with virus-killing forceps and lay it flat on the surface of each square piece to ensure that the diluted virus solution is in full and uniform contact with the surface of the square piece, place it in a petri dish, and place it in a constant temperature incubator at 37°C for 24 h, and measure the virus data every eight hours.

[0038] The antiviral copolyester film material P2, with the antiviral performance index value M on its surface v is 3.22, meeting the conditions for sufficient antiviral protection, and it is an antiviral material with good performance. It can be further used as the base material for medical protective equipment, such as making surgical gowns and surgical caps, so that the surgical gowns and surgical caps have good antiviral effects.

[0039] Example 3: 3.749 g (0.036 mol) of neopentyl glycol, 3.099 g (0.018 mol) of 1,4-cyclohexanedicarboxylic acid, 2.378 g (0.014 mol) of 2,5-pyrimidinedicarboxylic acid and 0.069 g of monobutyltin oxide were successively added to a 50 ml single-necked flask. Nitrogen was introduced for protection, and the reaction was stirred at 160 °C under atmospheric pressure for 4 h to obtain an esterification product. The esterification product was further heated to 230 °C, and the absolute pressure in the reaction system was controlled at about 100 Pa, and the reaction was carried out for 3 h to obtain a crude polycondensation product. A sufficient amount of chloroform was added to the crude polyester, and after shaking to promote dissolution, it was soaked for 2 h, centrifuged and precipitated, and filtered; the clear liquid was added dropwise to 50 ml of methanol to obtain a turbid liquid, and a precipitate was formed until the precipitate no longer increased. It was centrifuged and separated again, filtered to obtain a solid, and the obtained solid was washed with cold ethanol, and the solid after filtration was dried at 70 °C for 2 h to obtain the required environmentally friendly copolyester P3: 7.873 g, and the yield was 91.37%. After testing, the number average molecular weight was 3.35×10 4 g / mol, the flexural strength was 99.7 MPa, the tensile strength was 74.9 MPa, and the elongation at break was 270.6%.

[0040] Preparation of antiviral copolyester film: Collect 100 g of copolyester P3, mix it evenly with 1 g of chain extender epoxide ADR-4368-C, 1.0 g of antioxidant 3114, 0.5 g of antioxidant 168, and 10 ml of liquid paraffin, and granulate it after mixing and extruding with a twin-screw extruder; Through the blow molding process, a copolyester film is obtained; Weigh 10 g of polyvinylpyrrolidone PVP, add a sufficient volume of ethanol aqueous solution with a concentration of 50%, and stir well to obtain 200 g of dispersant solution R; Take 140 g of dispersant solution R, add sodium thiosulfate to prepare a Na2S2O3 solution with a concentration of 1.7 g / L; Take another 60 g of dispersant solution R and prepare an AgNO3 solution with a concentration of 1.7 g / L; Slowly drop the AgNO3 solution into the Na2S2O3 solution. After dropping, stir in the dark for 4 hours to obtain an Ag2S-polyvinylpyrrolidone PVP sol; Fix one end of the prepared copolyester film, and slowly immerse the other end into the above Ag2S-polyvinylpyrrolidone PVP sol to make its surface infiltrated with the Ag2S-polyvinylpyrrolidone PVP sol. After reaching adsorption equilibrium, slowly pull it out and dry it to obtain a uniform and dense antiviral copolyester film. Respectively take 0.6 ml of artificially cultured diluted virus solutions H1N1 and H3N2, and drop them on the surfaces of 60 mm×60 mm square pieces of the antiviral copolyester P3 film with the mass fractions of Ag2S in the antiviral diluent being 0.2%, 0.4%, 0.8%, and 1.2%. Then pick up the polyethylene covering film with virus-killing forceps and lay it flat on the surface of each square piece to ensure that the diluted virus solution is in full and uniform contact with the surface of the square piece. Place it in a petri dish and place it in a 37°C constant temperature incubator for 24 h, and measure the virus data every eight hours.

[0041] For the antiviral copolyester film material P3, the surface antiviral performance index value M v is 3.31, meeting the conditions for sufficient antiviral effect. It is an antiviral material with good performance and can be further used as the base material for medical protective equipment, such as making surgical gowns and surgical caps, so that the surgical gowns and surgical caps have good antiviral effects.

[0042] Example 4: 3.749 g (0.036 mol) of neopentyl glycol, 3.444 g (0.020 mol) of 1,4-cyclohexanedicarboxylic acid, 2.378 g (0.014 mol) of 2,5-pyrimidinedicarboxylic acid and 0.069 g of monobutyltin oxide were successively added to a 50 ml single-necked flask. Nitrogen was introduced for protection, and the reaction was stirred at 160 °C under atmospheric pressure for 4 h to obtain an esterification product. The esterification product was further heated to 230 °C, and the absolute pressure in the reaction system was controlled at about 100 Pa, and the reaction was carried out for 3 h to obtain a crude polycondensation product. Sufficient chloroform was added to the crude polyester, and after shaking to promote dissolution, it was soaked for 2 h, centrifuged and precipitated, and filtered; the clear liquid was added dropwise to 50 ml of methanol to obtain a turbid liquid, and a precipitate was formed until the precipitate no longer increased. It was centrifuged and separated again, filtered to obtain a solid, and the obtained solid was washed with cold ethanol, and the solid after filtration again was dried at 70 °C for 2 h to obtain the required environmentally friendly copolyester P4: 8.470 g, and the yield was 92.46%. After testing, the number-average molecular weight was 3.64×10 4 g / mol, the flexural strength was 113.3 MPa, the tensile strength was 88.1 MPa, and the elongation at break was 291.4%.

[0043] Preparation of antiviral copolyester film: Collect 100 g of copolyester P4, mix it evenly with 1 g of chain extender epoxide ADR-4368-C, 1.0 g of antioxidant 3114, 0.5 g of antioxidant 168, and 10 ml of liquid paraffin, and granulate after stirring and extruding with a twin-screw extruder; Through the blow molding process, a copolyester film is obtained; Weigh 10 g of polyvinylpyrrolidone PVP, add a sufficient amount of ethanol aqueous solution with a volume concentration of 50%, and stir well to obtain 200 g of dispersant solution R; Take 140 g of dispersant solution R, add sodium thiosulfate to prepare a Na2S2O3 solution with a concentration of 1.7 g / L; Take another 60 g of dispersant solution R and prepare an AgNO3 solution with a concentration of 1.7 g / L; Slowly drip the AgNO3 solution into the Na2S2O3 solution. After dripping, stir in the dark for 4 hours to obtain an Ag2S-polyvinylpyrrolidone PVP sol; Fix one end of the prepared copolyester film, and slowly immerse the other end into the above Ag2S-polyvinylpyrrolidone PVP sol to make its surface infiltrate with the Ag2S-polyvinylpyrrolidone PVP sol, reach adsorption equilibrium, and then slowly pull it out. After drying, a uniform and dense antiviral copolyester film is obtained. Respectively take 0.6 ml of artificially cultured diluted virus solutions H1N1 and H3N2, and drop them on the surfaces of 60 mm×60 mm square pieces of antiviral copolyester P4 film with the mass fractions of antiviral diluent Ag2S being 0.2%, 0.4%, 0.8%, and 1.2%. Then use a virus-killing forceps to pick up the polyethylene covering film and lay it flat on the surface of each square piece to ensure that the diluted virus solution is in full and uniform contact with the surface of the square piece. Place it in a petri dish and place it in a 37°C constant temperature incubator for 24 h, and measure the virus data every eight hours.

[0044] The antiviral copolyester film material P4, with the antiviral performance index value M on its surface v is 3.38, meeting the conditions for sufficient antiviral properties. It is an antiviral material with good performance and can be further used as the substrate for medical protective equipment, such as making surgical gowns and surgical caps, so that the surgical gowns and surgical caps have good antiviral effects.

[0045] Example 5: 3.749 g (0.036 mol) of neopentyl glycol, 3.099 g (0.018 mol) of 1,4-cyclohexanedicarboxylic acid, 2.594 g (0.015 mol) of 2,5-pyrimidinedicarboxylic acid and 0.069 g of monobutyltin oxide were successively added to a 50 ml single-necked flask. Nitrogen was introduced for protection, and the reaction was stirred at 160 °C under atmospheric pressure for 4 h to obtain an esterification product. The esterification product was further heated to 230 °C, and the absolute pressure in the reaction system was controlled at about 100 Pa, and the reaction was carried out for 3 h to obtain a crude polycondensation product. Sufficient chloroform was added to the crude polyester, and after shaking to promote dissolution, it was soaked for 2 h, centrifuged and precipitated, and filtered; the clear liquid was added dropwise to 50 ml of methanol to obtain a turbid liquid, and a precipitate was formed until the produced precipitate no longer increased. It was centrifuged and separated again, filtered to obtain a solid. The obtained solid was washed with cold ethanol, and the solid after filtration was dried at 70 °C for 2 h to obtain the required environmentally friendly copolyester P5: 8.204 g, with a yield of 93.16%. After testing, the number-average molecular weight was 3.59×10 4 g / mol, the flexural strength was 108.5 MPa, the tensile strength was 82.3 MPa, and the elongation at break was 285.8%.

[0046] Preparation of antiviral copolyester film: Collect 100 g of copolyester P5, mix it evenly with 1 g of chain extender epoxide ADR-4368-C, 1.0 g of antioxidant 3114, 0.5 g of antioxidant 168, and 10 ml of liquid paraffin, and cut into pellets after stirring and extruding with a twin-screw extruder; through a blow molding process, obtain a copolyester film; weigh 10 g of polyvinylpyrrolidone PVP, add a sufficient volume of ethanol aqueous solution with a concentration of 50%, and stir well to obtain 200 g of dispersant solution R; take 140 g of dispersant solution R, add sodium thiosulfate to prepare a Na2S2O3 solution with a concentration of 1.7 g / L; take another 60 g of dispersant solution R and prepare an AgNO3 solution with a concentration of 1.7 g / L; slowly drip the AgNO3 solution into the Na2S2O3 solution, and after dripping, stir in the dark for 4 hours to obtain an Ag2S-polyvinylpyrrolidone PVP sol; fix one end of the prepared copolyester film, slowly immerse the other end into the above Ag2S-polyvinylpyrrolidone PVP sol to make its surface infiltrated with the Ag2S-polyvinylpyrrolidone PVP sol, reach adsorption equilibrium, then slowly pull it out, and dry it to obtain a uniform and dense antiviral copolyester film. Respectively take 0.6 ml of artificially cultured diluted virus solutions H1N1 and H3N2, and drop them on the surfaces of 60 mm×60 mm square pieces of the antiviral copolyester P5 film with the mass fractions of Ag2S in the antiviral diluent being 0.2%, 0.4%, 0.8%, and 1.2% respectively, then pick up the polyethylene covering film with virus-killing forceps and lay it flat on the surface of each square piece to ensure that the diluted virus solution is in full and uniform contact with the surface of the square piece, place it in a petri dish, and place it in a 37°C constant temperature incubator for 24 h, and measure the virus data every eight hours.

[0047] The antiviral copolyester film material P5, with the antiviral performance index value M on its surface v is 3.44, meeting the conditions for sufficient antiviral ability, and it is an antiviral material with good performance. It can be further used as the base material for medical protective equipment, such as making surgical gowns and surgical caps, so that the surgical gowns and surgical caps have good antiviral effects.

[0048] Example 6: 3.749 g (0.036 mol) of neopentyl glycol, 3.444 g (0.020 mol) of 1,4-cyclohexanedicarboxylic acid, 2.594 g (0.015 mol) of 2,5-pyrimidinedicarboxylic acid and 0.069 g of monobutyltin oxide were successively added to a 50 ml single-necked flask. Nitrogen was introduced for protection, and the reaction was stirred at 160 °C under atmospheric pressure for 4 h to obtain an esterification product. The esterification product was further heated to 230 °C, and the absolute pressure in the reaction system was controlled at about 100 Pa, and the reaction was carried out for 3 h to obtain a crude polycondensation product. Sufficient chloroform was added to the crude polyester, and after shaking to promote dissolution, it was soaked for 2 h, centrifuged and precipitated, and filtered; the clear liquid was slowly added dropwise to 50 ml of methanol to obtain a turbid liquid and a precipitate was formed until the produced precipitate no longer increased. It was centrifuged and separated again, filtered to obtain a solid, and the obtained solid was washed with cold ethanol, and the solid after filtration again was dried at 70 °C for 2 h to obtain the required environmentally friendly copolyester P6: 8.800 g, with a yield of 93.88%. After testing, the number-average molecular weight was 3.76×10 4 g / mol, the flexural strength was 120.4 MPa, the tensile strength was 95.6 MPa, and the elongation at break was 300.5%.

[0049] Preparation of antiviral copolyester film: Collect 100g of copolyester P6, mix it evenly with 1g of chain extender epoxy compound ADR-4368-C, 1.0g of antioxidant 3114, 0.5g of antioxidant 168, and 10ml of liquid paraffin, use a twin-screw extruder to stir and extrude, and then cut into pellets; obtain a copolyester film through a blow molding process; weigh 10g of polyvinylpyrrolidone PVP, add a sufficient amount of ethanol aqueous solution with a volume concentration of 50%, stir thoroughly, and obtain 200g of dispersant solution R; take 140g of dispersant solution R, add sodium thiosulfate, and prepare it to a concentration of 1.7g / L Na2S2O3 solution; take another 60g of dispersant solution R to prepare an AgNO3 solution with a concentration of 1.7g / L; slowly add the AgNO3 solution dropwise to the Na2S2O3 solution, and after the addition is complete, stir in the dark for 4 hours to obtain an Ag2S-polyvinyl pyrrolidone PVP sol; fix one end of the prepared copolyester film, and slowly immerse the other end in the above-mentioned Ag2S-polyvinyl pyrrolidone PVP sol to wet the surface of the film with the Ag2S-polyvinyl pyrrolidone PVP sol to reach adsorption equilibrium, and then slowly pull it out and dry it to obtain a uniform and dense antiviral copolyester film. Take 0.6 ml of artificially cultured diluted virus liquid H1N1 and H3N2 respectively, and drop them on the surface of 60mm×60mm square pieces of antiviral copolyester P6 film with antiviral diluent Ag2S mass fraction of 0.2%, 0.4%, 0.8% and 1.2%, respectively. Then use virus-killing tweezers to pick up the polyethylene covering film and spread it flat on the surface of each square to ensure that the diluted virus liquid is in full and uniform contact with the surface of the square. Place it in a culture dish and place it in a constant temperature incubator at 37℃ for 24 hours. Measure the virus data every eight hours.

[0050] Antiviral copolyester film material P6, its surface antiviral performance index value M v The content of 3.49 has reached the conditions of full antiviral properties. It is an antiviral material with good performance and can be further used as the base material of medical protective equipment, such as surgical gowns and surgical caps, so that surgical gowns and surgical caps have good antiviral effects.

[0051] Table 1 Comparison of mechanical properties of copolyester samples P1 to P6 and properties of polypropylene composites

[0052]

[0053] [8] Yang Xiongnan, Zhang Xiaolin, Duan Jingting, Xu Long, Li Shaoge, Zhuo Guangming. Effects of several fillers on the properties of jute fiber / polypropylene composites [J]. New Chemical Materials, 2022, 50(06): 209-214.

[0054] Table 2 Antiviral infection performance of copolyester films

[0055]

[0056] Table 3 Results of the anti-microbial penetration (dry state) test and standard performance requirements

[0057]

[0058] Table 4 Results of the anti-microbial penetration (wet state) test and product standard performance requirements

[0059]

[0060] [9] Liu Zhongyou, Zheng Yangyu, Luo Qingxiang, Ke Jiechi. Test and analysis of the barrier effect of medical non-woven fabrics [J]. Technical Textiles, 2017, 35(09): 24-27.

[0061] In Table 1, Mn is the number-average molecular weight of the sample, [η1] is the initial intrinsic viscosity of the sample, and [η2] is the intrinsic viscosity of the sample after 3 years of degradation in the natural soil environment.

[0062] From the data comparison in Table 1, it can be seen that the number-average molecular weight of the biodegradable bio-copolyester P1-P6 synthesized from neopentyl glycol, 1,4-cyclohexanedicarboxylic acid and 2,5-pyrimidinedicarboxylic acid as raw materials in the present invention is higher than that of the polypropylene composite material, and the tensile strength is 40-70 MPa higher than that of the polypropylene composite material; from the comparison of [η1] and [η2] in Table 1, it can be seen that a biodegradable bio-copolyester synthesized in the present invention degrades in the natural soil environment, and the intrinsic viscosity of the polyester decreases by more than 18% after 3 years, which shows from another aspect that the molecular weight of the polyester is greatly reduced and it is easily degraded by the soil in the environment after being discarded. As can be seen from Table 2, the antiviral biodegradable bio-copolyester film synthesized from neopentyl glycol, 1,4-cyclohexanedicarboxylic acid and 2,5-pyrimidinedicarboxylic acid as raw materials in the present invention has good antiviral effects, and the antiviral effect becomes more obvious as the content of Ag2S in the copolyester film increases. When the mass fraction of Ag2S reaches 1.2%, the inhibition rate of influenza virus H1N1 reaches 99.37%, and the inhibition rate of influenza virus H3N2 reaches 98.63%.

[0063] Medical non-woven fabrics often use polypropylene as the main raw material. Based on the processing technology, the commonly used medical non-woven fabrics mainly include: spunbonded thin polypropylene non-woven fabric composite with PE film (hereinafter referred to as "spunbonded laminated fabric"), polypropylene spunbond / meltblown / spunbond composite non-woven fabric (hereinafter referred to as "SMS"). According to the Classification Catalogue of Medical Devices in China, medical non-woven fabric products are classified as class II products in 6864 Medical Sanitary Materials and Dressings, based on the standard YY / T 0506.2—2009 "Surgical drapes, gowns and clean air suits for patients, operating personnel and equipment - Part 1: Performance requirements and performance levels" and a series of standards. The performance parameters involved in the standard include microbial penetration resistance (dry state), microbial penetration resistance (wet state), lint shedding, water penetration resistance, bursting strength, etc.

[0064] Table 3 shows the test results of microbial penetration resistance (dry state) and the standard performance requirements. Diluted virus solutions H1N1 and H3N2 cultured artificially were used. Using a dry state penetration tester, a vibration test was carried out at a certain vibration frequency to test the ability of the test sample to resist microbial penetration in the dry state. The test results were judged according to the standard performance requirements of YY / T 0506.2—2009, expressed as the logarithm of the colony forming unit (CFU). It can be seen from the test results in Table 3 that the log 10 CFU values of the test samples all meet the standard performance requirements, indicating that the test samples all have the performance of resisting microbial penetration in the dry state, but the antiviral degradable bio-copolyester prepared by the present invention has more excellent performance effects.

[0065] Table 4 shows the test results of microbial penetration resistance (wet state) and the product standard performance requirements. Diluted virus solutions H1N1 and H3N2 cultured artificially were diluted to a certain concentration and made into test pieces. Together with the test materials, they were loaded into a wet state penetration tester for a mechanical friction test for a certain period of time to test the ability of the test sample to resist microbial penetration in the wet state. The test results were judged according to the standard performance requirements of YY / T 0506.2—2009, expressed as the barrier index IB, that is, the fraction of the challenging microorganisms that did not penetrate the barrier. It can be seen from the test results in Table 4 that the IB values of the test samples all meet the standard performance requirements, indicating that the test samples all have the performance of resisting microbial penetration in the wet state, but the antiviral degradable bio-copolyester prepared by the present invention has more excellent performance effects.

[0066] In summary, the copolyester films reported in the existing literature have disadvantages such as poor mechanical properties, being easily infected by viruses during use, and being difficult to degrade under natural conditions, making it difficult to meet the various requirements for material properties in practical applications. To address the problems in the prior art, the main objective of the present invention is to provide a biodegradable bio-copolyester, the preparation and application of an antiviral copolyester film. Specifically, neopentyl glycol, 1,4-cyclohexanedicarboxylic acid, and 2,5-pyrimidinedicarboxylic acid are used as raw materials to synthesize a biodegradable bio-copolyester through catalytic esterification and catalytic polycondensation reactions. The biodegradable bio-copolyester P prepared in the present invention is made into a film, and the surface of the film is fully wetted with a self-made Ag2S-polyvinylpyrrolidone PVP sol to form an antiviral copolyester film, which is next used as the substrate for preparing antiviral medical devices. Compared with the existing antiviral materials, it has strong mechanical properties, good flexibility, excellent antiviral performance, is harmless to the environment, and is easily degraded by the environment. Therefore, the invention application "Preparation and Application of a Biodegradable Bio-Copolyester and an Antiviral Copolyester Film" will have a good market prospect.

[0067] Although the preferred embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications to these embodiments once they learn the basic creative concept. Therefore, the appended claims are intended to be construed as including the preferred embodiments as well as all changes and modifications falling within the scope of the present invention. Obviously, those skilled in the art can make various changes and variations to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims

1. Application of a biodegradable bio-copolyester P in preparing a substrate for antiviral medical devices, characterized in that, The structure of the degradable bio-copolyester P is shown in Formula 1: ； Formula 1 Wherein: X in Formula 1 is 108 to 137, and Y is 110 to 138; The degradable bio-copolyester P is prepared by the following method: (1) Synthesis of crude copolyester: neopentyl glycol with CAS number 126-30-7 is used as an alcohol source, 1,4-cyclohexanedicarboxylic acid with CAS number 1076-97-7 is used as a first acid source, and 2,5-pyrimidinedicarboxylic acid with CAS number 127527-24-6 is used as a second acid source. The molar ratio of alcohol source: first acid source: second acid source = 10: (5-5.7): (3.5-4.2) is added to a reaction vessel, and an appropriate amount of catalyst monobutyltin oxide is added. Nitrogen is introduced for protection, and the reaction is stirred at 150-180°C for 2-4 hours to obtain an esterification product. The esterification product is further heated to 220-240°C, and the absolute pressure in the reaction system is controlled at 90-140 Pa. The polycondensation reaction is carried out for 2-4 hours under sufficient stirring to obtain a crude copolyester. (2) Purification of crude copolyester: The crude copolyester is dissolved in chloroform, filtered, and the supernatant is taken. An appropriate amount of low-carbon alcohol is added to the supernatant until the precipitation no longer increases. The solution is centrifuged and filtered. The resulting solid is washed with ethanol and filtered. The filtered solid is dried at 60-70°C for 1-2 h to obtain a biodegradable biocopolyester P. The method for preparing a substrate for an antiviral medical device comprises: 1) Preparation of copolyester film: Weigh 100 parts by weight of the biodegradable biocopolyester P, mix uniformly with 1 part by weight of the chain extender epoxy compound ADR-4368-C, 1 part by weight of the antioxidant 3114, 0.5 parts by weight of the antioxidant 168, and 1-5 parts by weight of liquid paraffin, extrude the mixture using a twin-screw extruder, and pelletize the mixture; then, mix uniformly with 10 parts by weight of the toughening agent PEG, and blow mold the mixture to obtain a dry and clean copolyester film; 2) Preparation of Ag2S-polyvinylpyrrolidone PVP sol: Step 1: Prepare dispersant solution R, weigh 10 parts by mass of PVP with a molecular weight of 8900 g / mol, add 190 parts by mass of an ethanol aqueous solution with a volume concentration of 50%, and stir thoroughly to obtain 200 parts by mass of dispersant solution R; Step 2: Take 140 parts by mass of dispersant solution R, add sodium thiosulfate, and prepare a Na2S2O3 solution with a concentration of 2.0-2.5 g / L; Take another 60 parts by mass of dispersant solution R and prepare an AgNO3 solution with a concentration of 2.0-2.5 g / L; Slowly add the AgNO3 solution prepared in the second step to the Na2S2O3 solution prepared in the first step, and after the addition is complete, stir in the dark for 2-4 hours to obtain Ag2S-polyvinylpyrrolidone PVP sol; 3) Preparation of antiviral polyester film: Fix one end of the dry and clean copolyester film prepared in step 1), and slowly immerse the other end into the Ag2S-polyvinylpyrrolidone PVP sol, so that its surface is fully wetted with the Ag2S-polyvinylpyrrolidone PVP sol to reach adsorption equilibrium. Then slowly pull out the copolyester film and dry it to obtain a uniform and dense antiviral copolyester film, which is processed into a medical substrate, including the substrates for doctor's surgical gowns, surgical caps, surgical gloves, surgical sheets, and disposable antiviral sheets for wards and guest rooms.

2. The application according to claim 1, wherein The appropriate amount of catalyst monobutyltin oxide in step (1) is 0.05%-0.15% of the amount of neopentyl glycol in terms of the amount of substance.

3. The application according to claim 2, characterized in that, The lower alcohol in step (2) is one of methanol, ethanol, and isopropanol.

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