Natural herbaceous plant modified biodegradable antibacterial composite material as well as preparation method and application thereof
A natural antibacterial composite material was prepared by blending nano-diatomaceous earth modified with extracts of Artemisia argyi and dandelion with PBAT. This solved the problems of easy loss of Chinese medicine components and the hazards of nanoparticles, and achieved efficient, safe antibacterial properties and biodegradability.
Patent Information
- Application Number
- CN202511526583.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-24
- Publication Date
- 2026-02-06
AI Technical Summary
The traditional Chinese medicine components in existing PBAT antibacterial materials are easily lost with use, making it difficult to meet product requirements for antibacterial performance, and the nanoparticles pose potential harm to the human body.
Nano-diatomaceous earth was modified using extracts of Artemisia argyi and dandelion to utilize the antibacterial effects of its volatile oils and flavonoids, and the porous structure of diatomaceous earth was used to stabilize the load, thus preparing PBAT blend materials.
The prepared composite material maintains good mechanical properties while significantly improving antibacterial properties, exhibiting sustained inhibitory effects on common bacteria. Furthermore, the components are safe, non-toxic, and easily degradable, making it suitable for multiple fields.
Smart Images
Figure CN121471672A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of antibacterial technology of biodegradable polyester, specifically to a biodegradable antibacterial composite material modified with natural herbal plants, its preparation method, and its application. Background Technology
[0002] Polybutylene adipate (PBAT) is widely used in packaging, agricultural films, and other fields due to its excellent flexibility, processability, and complete biodegradability. The preparation of a biodegradable antibacterial material has also become a hot topic in the field of biodegradable materials research.
[0003] Most current research on PBAT antibacterial materials utilizes blends modified PBAT with antibacterial nanoparticles (such as nano-zinc oxide and nano-silver oxide). However, these nanoparticles can cause varying degrees of harm to the human body, limiting their application. To address this issue, many studies have also modified PBAT using extracts or residues of traditional Chinese medicine to prepare PBAT composite materials with antibacterial properties. However, this method also has several drawbacks, such as the easy loss of herbal components during material use, making it difficult to achieve the required antibacterial performance for product applications. Summary of the Invention
[0004] The purpose of this invention is to provide a biodegradable antibacterial composite material modified with natural herbal plants, in order to solve the technical problem that the components of traditional Chinese medicine are easily lost with the use of the material, and the antibacterial performance is difficult to meet the requirements of product use.
[0005] Artemisia argyi and dandelion, as traditional Chinese herbal medicines, contain extracts with volatile oils, flavonoids, polysaccharides, and other components that exhibit clear antibacterial effects. Multiple scientific studies have confirmed that they have low toxicity and are safe for human use at normal dosages. Furthermore, the extracts of Artemisia argyi and dandelion contain many organic groups, which can effectively modify the surface of inorganic particles. Diatomaceous earth, a porous inorganic material with good adsorption and stability, can effectively carry the effective components of Artemisia argyi and dandelion extracts as a carrier. This allows the modified diatomaceous earth to be evenly distributed during blending with PBAT, fully leveraging the antibacterial properties of the traditional Chinese medicines. The composite material obtained in this invention possesses excellent antibacterial properties and biodegradability while retaining certain mechanical properties. It is environmentally friendly and also broadens the application range of PBAT copolyesters.
[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A method for preparing a biodegradable antibacterial composite material modified with natural herbal plants, characterized by comprising the following steps: S1. Preparation of Traditional Chinese Medicine Extract Artemisia argyi and dandelion are mixed and then soaked in ethanol. The soaked herbal ethanol mixture is then added to a Soxhlet extractor to extract the extract. The extract is then filtered to remove solid impurities, thus obtaining the Chinese herbal extract. S2. Preparation of nano-diatomite Diatomaceous earth and anhydrous ethanol were mixed, titanate coupling agent was added, and then the mixture was placed in a ball mill for ball milling. After ball milling, the obtained diatomaceous earth-ethanol mixture was filtered and repeatedly washed with ethanol, and then dried in a vacuum oven to obtain nano-diatomaceous earth. S3. Preparation of modified diatomaceous earth for traditional Chinese medicine The traditional Chinese medicine extract from step S1 and the nano-diatomite from step S2 are mixed and stirred. The mixture is then filtered and dried in a vacuum oven to obtain the modified traditional Chinese medicine diatomite. S4. Preparation of antibacterial composite materials PBAT and herbal-modified diatomaceous earth were added to a torque rheometer, the temperature was raised to 165℃, the rotation speed was gradually increased to 80 r / min, and the mixture was stirred for 30 minutes. After the mixture was homogeneous, the material was taken out and allowed to cool naturally to obtain a biodegradable antibacterial composite material modified with natural herbal plants.
[0007] As a further limitation of the technical solution of the present invention, in step S1, the mass ratio of mugwort and dandelion is 1:1, the amount of ethanol added is twice the total mass of mugwort and dandelion, and the ethanol soaking time is 12h.
[0008] As a further limitation of the technical solution of the present invention, the extraction conditions in the Soxhlet extractor in step S1 are extraction at 60°C for 8 hours; and the filtration process is carried out in the sand core funnel in step S1.
[0009] As a further limitation of the technical solution of the present invention, in step S2, the mass ratio of diatomaceous earth to anhydrous ethanol is 1:1, the mass ratio of titanate coupling agent to diatomaceous earth is 1:1000, the ball milling time is 48h, and the drying conditions in the vacuum oven are 50℃ for 24h.
[0010] As a further limitation of the technical solution of the present invention, in step S3, the volume-to-mass ratio of the herbal extract to the nano-diatomite is 1 mL: 4 g, the mixing and stirring are carried out under magnetic stirring at 60°C for 8 h, and then dried in a vacuum oven at 50°C for 24 h.
[0011] As a further limitation of the technical solution of the present invention, the mass ratio of PBAT to modified diatomaceous earth of traditional Chinese medicine in step S4 is 97-85:3-15.
[0012] The present invention also provides a natural herbal modified biodegradable antibacterial composite material obtained by the above preparation method.
[0013] In addition, the present invention also provides the application of the above-mentioned natural herbal modified biodegradable antibacterial composite material in the preparation of food packaging, biomedical materials and agricultural covering films.
[0014] Compared with the prior art, the present invention has the following beneficial effects: This invention modifies nano-diatomaceous earth using a mixed extract of dandelion and artemisia, loading a certain amount of effective antibacterial components from traditional Chinese medicine into its pores. The composite material uses biodegradable PBAT copolyester as the matrix and modified diatomaceous earth as the filler. The modified diatomaceous earth, as a functional filler, is thoroughly mixed with PBAT copolyester at 165°C through a melt blending process. The modified diatomaceous earth exhibits good dispersion in the matrix, effectively releasing the herbal components and significantly improving the antibacterial properties of the material, especially showing sustained inhibitory effects against common bacteria (such as Escherichia coli and Staphylococcus aureus). Compared with traditional biodegradable antibacterial materials, the antibacterial components used in this invention are derived from natural plants, making them green, safe, and non-toxic. They are also less prone to migration or release, avoiding potential environmental or health hazards. Furthermore, the material can be completely degraded under natural conditions or the action of specific microorganisms, meeting the requirements of environmental protection policies and green development strategies, and possessing excellent prospects for widespread application. It is suitable for multiple fields such as biodegradable packaging films, medical dressings, and agricultural covering films. Attached Figure Description
[0015] Figure 1 The image shown is a cross-sectional SEM image of the antibacterial composite material prepared in Example 6 of this invention. The right image is a partial enlarged view of the left image.
[0016] Figure 2 The images show the antibacterial properties of the composite materials prepared in Comparative Example 1 and Examples 4-8 against Escherichia coli, where (a) is Comparative Example 1, (b) is Example 4, (c) is Example 5, (d) is Example 6, (e) is Example 7, and (f) is Example 8.
[0017] Figure 3 The images show the antibacterial properties of the composite materials prepared in Comparative Example 1 and Examples 4-8 against Staphylococcus aureus, where (a) is Comparative Example 1, (b) is Example 4, (c) is Example 5, (d) is Example 6, (e) is Example 7, and (f) is Example 8. Detailed Implementation
[0018] The present invention will be further described below with reference to specific embodiments. Example 1
[0019] Preparation of Chinese herbal extracts Mugwort (100g) and dandelion (100g) were mixed in a 1:1 mass ratio, and then soaked in 400g of ethanol (2 times the amount) for 12 hours. The soaked herbal ethanol mixture was then added to a Soxhlet extractor and extracted at 60°C for 8 hours to obtain the desired herbal extract. The herbal extract was then filtered using a sand core funnel to remove solid impurities, and finally a mixed herbal extract of dandelion and mugwort was obtained. Example 2
[0020] Preparation of nano-diatomite Diatomaceous earth (500g) and anhydrous ethanol (500g) were mixed in a 1:1 ratio, and 0.5g of titanate coupling agent was added. The mixture was then ball-milled for 48h. After ball milling, the resulting diatomaceous earth-ethanol mixture was filtered and rinsed with ethanol three times. After most of the ethanol was filtered out, the mixture was placed in a vacuum oven at 50°C for 24h to obtain the desired nano-diatomaceous earth. Example 3
[0021] Preparation of modified diatomite from traditional Chinese medicine The herbal extract obtained in Example 1 and the nano-diatomite obtained in Example 2 were mixed in a 1:4 ratio (herbal extract: 100ml, diatomite: 400g). The mixture was added to a beaker and magnetically stirred at 60°C for 8 hours. The resulting mixture was then filtered and dried in a vacuum oven at 50°C for 24 hours to obtain herbal modified diatomite. Example 4
[0022] 145.5g of PBAT and 4.5g of the modified diatomaceous earth obtained in Example 3 were added to a torque rheometer. The temperature was raised to 165℃, and the rotation speed was gradually increased to 80r / min for 30min. After uniform mixing, the resulting composite material was removed and allowed to cool naturally before being cut into small pieces for later use. 3g of the above composite material was placed in a 100×100×0.02mm mold and then placed in a flat vulcanizing machine. The antibacterial composite material was prepared by hot pressing and labeled as (b). Example 5
[0023] 141g of PBAT and 9g of herbal-modified diatomaceous earth were added to a torque rheometer. The temperature was raised to 165℃, and the rotation speed was gradually increased to 80r / min for 30min. After uniform mixing, the resulting composite material was removed and allowed to cool naturally before being cut into small pieces for later use. 3g of the composite material was placed into a 100×100×0.02mm mold and then placed in a flat vulcanizing machine. The antibacterial composite material was prepared by hot pressing and labeled as (c). Example 6
[0024] 136.5g of PBAT and 13.5g of herbal-modified diatomaceous earth were added to a torque rheometer. The temperature was raised to 165℃, and the rotation speed was gradually increased to 80r / min for 30min. After uniform mixing, the resulting composite material was removed and allowed to cool naturally before being cut into small pieces. 3g of the composite material was placed into a 100×100×0.02mm mold and then placed in a flat vulcanizing machine. The antibacterial composite material was prepared by hot pressing and labeled as (d). Example 7
[0025] 132g of PBAT and 18g of herbal-modified diatomaceous earth were added to a torque rheometer. The temperature was raised to 165℃, and the rotation speed was gradually increased to 80r / min for 30min. After uniform mixing, the resulting composite material was removed and allowed to cool naturally before being cut into small pieces. 3g of the composite material was placed into a 100×100×0.02mm mold and then placed in a flat vulcanizing machine. The antibacterial composite material, labeled (e), was prepared by hot pressing. Example 8
[0026] 127.5g of PBAT and 22.5g of herbal-modified diatomaceous earth were added to a torque rheometer. The temperature was raised to 165℃, and the rotation speed was gradually increased to 80r / min for 30min. After uniform mixing, the resulting composite material was removed and allowed to cool naturally before being cut into small pieces. 3g of the composite material was placed into a 100×100×0.02mm mold and then placed in a flat vulcanizing machine. The antibacterial composite material, labeled (f), was prepared by hot pressing.
[0027] Compare with Example 1 Take 3g of PBAT and put it into a 100×100×0.02mm mold, then put it into a flat vulcanizing machine, and prepare the composite material by hot pressing, which is labeled as (a).
[0028] Performance testing: The antibacterial properties of the materials prepared in Examples 4-8 and Comparative Example 1 were determined according to the standard GB / T31402-2023 "Determination of antibacterial activity of plastics and other non-porous materials". The structures are shown in Table 1. Figure 2-3 As shown. Tensile strength tests were performed on Examples 4-8 and Comparative Example 1 according to GB / T1040-2006 "Determination of Tensile Properties of Plastics". The interfacial bonding between the filler and matrix in the composite material obtained in Example 6 was analyzed using scanning electron microscopy (SEM). Figure 1 As shown.
[0029] The test results of the relevant performance of the obtained samples are shown in the table below: Table 1 shows the results of the antibacterial performance tests on the materials prepared in Examples 4-8 and Comparative Example 1.
[0030] Table 2 shows the tensile strength test results of Examples 4-8 and Comparative Example 1.
[0031] Antibacterial tests against *Escherichia coli* and *Staphylococcus aureus* were performed on Comparative Example 1 and Examples 4-8. During the tests, the bacteria were diluted 10-fold five times, with a sample volume of 0.2 ml, and the bacterial concentration was calculated. (See attached...) Figure 2 and 3 It can be observed that Examples 4-8 exhibit certain antibacterial effects against both *Escherichia coli* and *Staphylococcus aureus*. The bacterial concentrations in Examples 4-8 all show a decreasing trend, with the *E. coli* concentration decreasing from 1.5 × 10⁻⁶. 8 CFU / ml up to 3.4 × 10 7 CFU / ml, Staphylococcus aureus concentration from 1.415×10 8 CFU / ml up to 1.75×10 7 CFU / ml. It can be observed that the antibacterial effect becomes more pronounced with increasing modified diatomaceous earth content, and the antibacterial effect against Staphylococcus aureus is even better. Comparative analysis of the mechanical properties data in the table above shows that the addition of modified diatomaceous earth slightly improves the tensile strength of the copolyester. However, with increasing proportion of modified diatomaceous earth, the elongation at break of the copolyester decreases, while retaining certain mechanical properties.
[0032] In summary, this invention functionalizes nano-diatomaceous earth by using a composite plant extract of Artemisia argyi and dandelion, stably loading the antibacterial active ingredients from traditional Chinese medicine into the porous structure of diatomaceous earth, effectively improving the dispersibility and stability of the antibacterial components in the material. Subsequently, this modified diatomaceous earth was blended with PBAT to successfully prepare a biodegradable antibacterial composite material modified with natural herbs. This material not only maintains good mechanical properties under room temperature processing conditions but also significantly enhances its antibacterial ability against bacteria (such as Escherichia coli and Staphylococcus aureus). Furthermore, the antibacterial components are less prone to migration or release during material use, overcoming the problem of poor stability in traditional Chinese medicine-added antibacterial materials. In addition, all raw materials used are natural, non-toxic, and biodegradable, conforming to the material design concept of green and sustainable development. This invention provides a new approach for developing environmentally friendly, biosafety-high, and functionally stable biodegradable antibacterial polyester materials, with good prospects for promotion and application value, especially suitable for food packaging, biomedical materials, and agricultural covering films.
Claims
1. A method for preparing a biodegradable antibacterial composite material modified with natural herbal plants, characterized in that, Includes the following steps: S1. Preparation of Traditional Chinese Medicine Extract Artemisia argyi and dandelion are mixed and then soaked in ethanol. The soaked herbal ethanol mixture is then added to a Soxhlet extractor to extract the extract. The extract is then filtered to remove solid impurities, thus obtaining the Chinese herbal extract. S2. Preparation of nano-diatomite Diatomaceous earth and anhydrous ethanol were mixed, titanate coupling agent was added, and then the mixture was placed in a ball mill for ball milling. After ball milling, the obtained diatomaceous earth-ethanol mixture was filtered and repeatedly washed with ethanol, and then dried in a vacuum oven to obtain nano-diatomaceous earth. S3. Preparation of modified diatomaceous earth for traditional Chinese medicine The traditional Chinese medicine extract from step S1 and the nano-diatomite from step S2 are mixed and stirred. The mixture is then filtered and dried in a vacuum oven to obtain traditional Chinese medicine modified diatomite. S4. Preparation of antibacterial composite materials PBAT and herbal-modified diatomaceous earth were added to a torque rheometer, the temperature was raised to 165℃, the rotation speed was gradually increased to 80 r / min, and the mixture was stirred for 30 minutes. After the mixture was homogeneous, the material was taken out and allowed to cool naturally to obtain a biodegradable antibacterial composite material modified with natural herbal plants.
2. The method for preparing a natural herbal modified biodegradable antibacterial composite material according to claim 1, characterized in that, In step S1, the mass ratio of mugwort to dandelion is 1:1, the amount of ethanol added is twice the total mass of mugwort and dandelion, and the ethanol soaking time is 12 hours.
3. The method for preparing a biodegradable antibacterial composite material modified with natural herbal plants according to claim 1, characterized in that, In step S1, the extraction conditions in the Soxhlet extractor are 60℃ for 8 hours; in step S1, the filter is carried out in a sand core funnel.
4. The method for preparing a natural herbal modified biodegradable antibacterial composite material according to claim 1, characterized in that, In step S2, the mass ratio of diatomaceous earth to anhydrous ethanol is 1:1, the mass ratio of titanate coupling agent to diatomaceous earth is 1:1000, the ball milling time is 48 hours, and the drying conditions in the vacuum oven are 50°C for 24 hours.
5. The method for preparing a natural herbal modified biodegradable antibacterial composite material according to claim 1, characterized in that, In step S3, the volume-to-mass ratio of the herbal extract to nano-diatomaceous earth is 1 mL: 4 g. The mixture is magnetically stirred at 60°C for 8 hours and then dried in a vacuum oven at 50°C for 24 hours.
6. The method for preparing a biodegradable antibacterial composite material modified with natural herbal plants according to claim 1, characterized in that, In step S4, the mass ratio of PBAT to modified diatomaceous earth is 97-85:3-15.
7. The natural herbal plant-modified biodegradable antibacterial composite material obtained by the preparation method according to any one of claims 1-6.
8. The application of the natural herbal modified biodegradable antibacterial composite material according to claim 7 in the preparation of food packaging, biomedical materials and agricultural covering films.