Straw fiber-based antibacterial mulching film with temperature and humidity response performance and preparation method thereof

Abstract

The application discloses a straw fiber base bacteriostatic mulch with temperature and humidity response performance and a preparation method thereof, and belongs to the technical field of agricultural mulch. The straw fiber base bacteriostatic mulch with temperature and humidity response performance comprises, from bottom to top, a bottom film layer, a slow-release layer and a barrier layer. The slow-release layer is obtained by coating a mixed solution of acetic acid, a bactericide, gelatin and a plasticizer onto the bottom film layer. The barrier layer is obtained by coating palm wax emulsion on the surface of the slow-release layer. That is, the straw fiber base bacteriostatic mulch with temperature and humidity response performance is constructed by combining palm wax, a bactericide (carbendazim), gelatin and a wheat straw fiber base mulch. The straw fiber base bacteriostatic mulch can respond to changes in environmental temperature and humidity, realize accurate release of pesticides, and thus accurately control diseases.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of agricultural mulching film, and particularly relates to a straw fiber-based antibacterial mulching film with temperature and humidity response performance and a preparation method. BACKGROUND

[0002] Environmental temperature and humidity have an important influence on the occurrence of crop diseases. Studies have shown that an increase in temperature will lead to a shortening of the latent period of diseases. Under suitable temperature conditions, an increase in humidity will lead to a large number of reproduction and spread of the pathogen. For example, under the conditions of high temperature and high humidity, soybean root rot is extremely easy to cause. The traditional disease control method can usually only be passive after the occurrence of diseases, and cannot respond to changes in environmental temperature and humidity, which has poor targeting and precision, and cannot maximize the role of pesticides, thereby causing problems such as pesticide residues, environmental pollution and ecological destruction, and has not met the requirements of agricultural health and sustainable development. Therefore, it is of great significance to scientifically design the pesticide dosage form, realize the response release of the pesticide according to the changes in environmental temperature and humidity, accurately control the diseases and improve the utilization rate of the pesticide.

[0003] In recent years, mulching technology has attracted much attention as an important means to improve the quality and yield of crops. It is reported that the area of plastic film mulching in global agricultural land is about 128,652 km 2 Traditional plastic mulch has good advantages such as insect prevention, weed prevention, heat preservation and moisture preservation. However, the residue of traditional plastic mulch has become a major problem for the sustainable development of agriculture. Straw fiber-based mulch is an excellent green alternative to traditional plastic or biodegradable mulch for farmland covering. This type of paper mulch not only does not cause soil pollution, but also provides a new method for straw returning to field, effectively improving the soil structure, fertility and nutrient content. At the same time, since its main raw material is cellulose, it can be used as a natural humidity-sensitive material. However, compared with plastic mulch, paper mulch also has problems such as low strength, poor flexibility and poor environmental temperature responsiveness. Therefore, it is of great significance to modify the straw fiber-based mulch. SUMMARY

[0004] In view of the above technical problems, the application provides a straw fiber-based antibacterial mulching film with temperature and humidity response performance and a preparation method. That is, the application takes a wheat straw fiber-based mulch (WFM) as a carrier, takes a broad-spectrum fungicide carbendazim as a model pesticide, and composites the pesticide molecules and the temperature-responsive material in a specific structure on the mulch to construct a wheat straw fiber-based temperature and humidity response type antibacterial mulch, so as to realize the response release of the pesticide according to the changes in environmental temperature and humidity, and accurately control the diseases.

[0005] To achieve the above purpose, the application provides the following technical scheme:

[0006] A straw fiber base bacteriostatic mulch film with temperature and humidity response performance, which comprises a bottom film layer and a slow-release layer from bottom to top;

[0007] Or,

[0008] It comprises a bottom film layer, a slow-release layer and a barrier layer from bottom to top;

[0009] The slow-release layer is obtained by coating a mixed solution of acetic acid, bactericide, gelatin and plasticizer onto the bottom film layer;

[0010] The barrier layer is obtained by coating a palm wax emulsion on the surface of the slow-release layer.

[0011] Beneficial effects: the present application discloses a straw fiber base bacteriostatic mulch film with temperature and humidity response performance, which has one or two coating layers, wherein the first layer is a mixture of temperature response slow-release agent gelatin and bactericide, and the second layer is a barrier layer formed by palm wax. The first layer can realize temperature intelligent response release of drugs, and the second layer is a regulation layer, which changes the coating amount of palm wax according to the use scene, so as to change the slow-release rule of the mulch film.

[0012] Optionally, the bottom film layer is a straw fiber base film, preferably a wheat straw fiber base film.

[0013] Optionally, the bactericide is carbendazim; and the plasticizer is glycerol.

[0014] Optionally, the thickness of the slow-release layer is 14.16-30 μm.

[0015] Further, the thickness of the slow-release layer is 20 μm.

[0016] Optionally, the thickness of the barrier layer is 10-30 μm.

[0017] A preparation method of a straw fiber base bacteriostatic mulch film with temperature and humidity response performance, comprising the following steps:

[0018] Gelatin, bactericide and plasticizer are added into an aqueous acetic acid solution, and stirred uniformly to obtain a mixed solution;

[0019] The mixed solution is coated onto the bottom film layer by using a wire bar coating technology to form a slow-release layer, thereby obtaining a straw fiber base bacteriostatic mulch film with temperature and humidity response performance comprising a bottom film layer and a slow-release layer;

[0020] A palm wax emulsion is coated onto the slow-release layer to form a barrier layer, thereby obtaining a straw fiber base bacteriostatic mulch film with temperature and humidity response performance comprising a bottom film layer, a slow-release layer and a barrier layer.

[0021] Beneficial effects: the application takes wheat straw fiber-based film, acetic acid, carbendazim, gelatin, palm wax and glycerol as main components. Among them, the wheat straw fiber-based film has a three-dimensional porous structure formed by hydrogen bonds of plant fibers, and is rich in hydrophilic groups such as hydroxyl groups, which is a natural wet-responsive material. Gelatin is rich in biological functional groups such as carboxyl, hydroxyl and amino groups, and has good natural biodegradability and temperature sensitivity, so it becomes a good pesticide temperature response release agent. Palm wax has strong hydrophobicity, which makes it difficult for water molecules to adhere or penetrate on its surface, thereby effectively preventing water from penetrating into the object, and the characteristics of palm wax make it have great potential in regulating the release of mulch. Broad-spectrum fungicide carbendazim is used as a model pesticide, gelatin is used as a release agent, and line bar coating technology is used to coat it on the surface of the mulch. This mulch can respond in time according to the change of environmental temperature and humidity, and realize accurate control of pesticide release. In order to make the application scene of the mulch wider and the controllable ability stronger, the application coats palm wax on the barrier layer of the mulch, controls the release time of the drug on the mulch through palm wax, and improves the controllability of the crop growth environment.

[0022] Optionally, the preparation process of the straw fiber-based antibacterial mulch with temperature and humidity response performance is specifically:

[0023] (1) Dissolve gelatin in acetic acid aqueous solution, stir until the gelatin is dissolved uniformly, then add plasticizer, continue to stir, and obtain solution 1;

[0024] (2) Stir the fungicide and acetic acid aqueous solution uniformly to obtain solution 2;

[0025] (3) Mix the solution 1 and the solution 2 uniformly to obtain solution 3 (C-Gel mixed solution);

[0026] (4) The solution 3 is coated on the wheat straw fiber-based mulch (WFM) by using line bar coating technology to obtain a C-Gel-WFM sample;

[0027] (5) The palm wax emulsion is coated on the surface of the C-Gel-WFM sample by using line bar coating technology to obtain a CW-C-Gel-WFM sample, that is, the straw fiber-based antibacterial mulch with temperature and humidity response performance.

[0028] Further, the loading amount of the fungicide in the C-Gel-WFM sample is 0.05-0.15 g / m 2 ; preferably 0.05 g / m 2 , 0.1 g / m 2 and 0.15 g / m 2 .

[0029] Optionally, in the solution 1, the concentration of the gelatin is 1.78%-2.24% (m / v), and the concentration of the plasticizer is 0.26%-0.35% (v / v).

[0030] Optionally, in the solution 1, the concentration of the gelatin is 2% (m / v).

[0031] Further, the concentration of the acetic acid aqueous solution is 2% (v / v).

[0032] Further, in the stirring process in the step (1), the stirring temperature is 50℃, and the stirring speed is 400 rpm.

[0033] Compared with the prior art, the present application has the following advantages and technical effects:

[0034] The present application combines palm wax, carbendazim, gelatin and wheat straw fiber-based film to construct a wheat straw fiber-based temperature and humidity responsive antibacterial mulching film. The mulching film can respond to changes in environmental temperature and humidity, achieving precise release of pesticides and thus precise control of diseases. BRIEF DESCRIPTION OF DRAWINGS

[0035] The accompanying drawings, which form a part of the present application, are used to provide further understanding of the present application, and the illustrative embodiments thereof and their descriptions serve to explain the present application, and do not constitute improper limitations on the present application. In the drawings:

[0036] Figure 1 is a column chart of the influence of different drug loading amounts on dry tensile strength;

[0037] Figure 2 is a column chart of the influence of different drug loading amounts on elongation at break;

[0038] Figure 3 is a column chart of the influence of different drug loading amounts on wet tensile strength;

[0039] Figure 4 is a microstructure diagram of the C-Gel-WFM sample prepared in Example 1, wherein a) is a 50 times electron microscope diagram, and b) is a 500 times electron microscope diagram;

[0040] Figure 5 is an FT-IR spectrum diagram of the wheat straw fiber film (WFM), gelatin / carbendazim (C-Gel), and carbendazim / gelatin / wheat straw fiber film (C-Gel-WFM) in Example 1;

[0041] Figure 6 is a carbendazim standard curve diagram;

[0042] Figure 7The graphs show the effects of different temperatures and drug loadings on drug release, where a) is the drug release curve at 20℃, b) is the drug release curve at 30℃, c) is the drug release curve at 40℃, and d) is the drug release curve at 0.05 g / m³. 2 The drug release curve, e), is 0.1 g / m³. 2 The drug release curve (f) is 0.15 g / m. 2 Drug release curve;

[0043] Figure 8 A bar chart showing the effect of different wet film thicknesses on dry tensile strength;

[0044] Figure 9 A bar chart showing the effect of different wet film thicknesses on wet tensile strength;

[0045] Figure 10 A bar chart showing the effect of different wet film thicknesses on sizing degree;

[0046] Figure 11 The images show the microstructure of CW-C-Gel-WFM prepared in Example 4, where a) is a 50x electron microscope image and b) is a 500x electron microscope image.

[0047] Figure 12 The FTIR spectra of CW-C-Gel-WFM, C-Gel-WFM and CW prepared in Example 4 are shown below.

[0048] Figure 13 The graphs show the effects of different temperatures and wet film thicknesses on drug release, where a) is the drug release curve at 20℃; b) is the drug release curve at 30℃; and c) is the drug release curve at 40℃.

[0049] Figure 14 The figures show the growth of soybeans after different treatments, where a) is CK, b) is carbendazim, c) is WFM, d) is Gel-WFM, e) is C-Gel-WFM, and f) is CW-C-Gel-WFM.

[0050] Figure 15 The figures show the growth and development of soybeans after different treatments, where a) is CK, b) is carbendazim, c) is WFM, d) is Gel-WFM, e) is C-Gel-WFM, and f) is CW-C-Gel-WFM.

[0051] Figure 16 A bar chart showing the effect of different treatments on soybean plant height;

[0052] Figure 17 Bar chart showing the effect of different treatments on the fresh weight of soybean plants;

[0053] Figure 18 Bar chart showing the effect of different treatments on soybean root dry weight;

[0054] Figure 19 The bar chart shows the effects of different treatments on soybean roots, where a) is CK, b) is carbendazim, c) is WFM, d) is Gel-WFM, e) is C-Gel-WFM, and f) is CW-C-Gel-WFM.

[0055] Figure 20 Bar chart showing the effect of different treatments on the soybean root rot index;

[0056] Figure 21 Bar chart showing the effect of different treatments on the incidence of soybean root rot. Detailed Implementation

[0057] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0058] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0059] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0060] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0061] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0062] Unless otherwise specified, "room temperature" in this invention refers to 20-30℃.

[0063] Unless otherwise specified, the term "parts" in this invention refers to parts by weight.

[0064] All raw materials used in this invention were purchased from the market. Wheat straw fiber: processed Dongnong Winter Wheat No. 2 wheat straw, obtained through a D200 straw fiber production mechanism; unbleached KP pulp; wet strength agent (solid content 12.5±0.5%); neutral sizing agent (solid content 12.5±0.5%); fungicide: carbendazim (Shanghai Yuanye Biotechnology Co., Ltd., active ingredient 96%); gelatin (Shanghai Aladdin Biochemical Technology Co., Ltd., CP); glycerin (Tianjin Fuyu Fine Chemical Co., Ltd., content ≥99.5%); palm wax emulsion (Kelepu Chemical Products Co., Ltd., solid content 30%); glacial acetic acid (analytical grade).

[0065] The test method is as follows:

[0066] (1) Mechanical property determination

[0067] Referring to GB / T12914-2008 "Determination of Tensile Strength of Paper and Paperboard", the dry and wet tensile strength and elongation at break of the film (12×1.5 cm) were measured using a pendulum paper tensile measuring instrument. The tensile strength S was calculated according to the formula, and the unit is expressed as kN / m. The test was performed 3 times and the average value was taken.

[0068] ;

[0069] Where: S—tensile strength, kN / m;

[0070] F – Tensile strength, N;

[0071] W – Membrane width, mm.

[0072] (2) Determination of sizing degree

[0073] The sizing degree of the film (3×3 cm) was determined according to GB / T 460-2008 "Determination of Sizing Degree of Paper". The unit is expressed as s. The test was performed 3 times and the average value was taken.

[0074] (3) Scanning electron microscopy (SEM) analysis

[0075] WFM and Gel-WFM were fabricated into 1×1 cm films, then sputter-coated with gold. The microstructure of the films before and after coating was analyzed using a desktop scanning electron microscope (TM4000, Hitachi, Japan).

[0076] (4) Fourier transform infrared (FTIR) spectroscopy analysis

[0077] Fourier transform infrared spectrometer (Thermo Fisher Nicolet iS50, Thermo Fisher Scientific, USA) was used at 400–4000 cm⁻¹. −1 FTIR spectroscopic analysis was performed on gelatin, WFM, Gel-WFM and glycerol samples within the specified range.

[0078] (5) Drug release behavior test

[0079] To investigate the carbendazim release behavior of C-Gel-WFM under different temperature conditions, a carbendazim release experiment was conducted. C-Gel-WFM was immersed in 120 mL of distilled water at corresponding temperatures of 20, 30, and 40 °C. At fixed time intervals, 10 mL of the extract containing the released drug component was taken from the solution for measurement. To maintain a constant total solution volume, an equal volume of distilled water was added after each extraction. Measurements were taken every hour for the first 0–12 hours, and then every 12 hours for the subsequent 12–240 hours. The concentration of carbendazim in the extract at different time points was determined using a TU-1810 UV-Vis spectrophotometer (Beijing Purkinje General Instrument Co., Ltd., Beijing) according to standard GB / T5009188-2003 at a wavelength of 282 nm.

[0080] The technical solution of the present invention will be further illustrated by the following embodiments.

[0081] Example 1

[0082] A method for preparing a straw fiber-based antibacterial mulch film with temperature and humidity responsive properties includes the following steps:

[0083] (1) Preparation of wheat straw fiber base film: WFM was prepared using Dongnong Dongmai No. 2 wheat straw as raw material, following the method described in the literature (ZHAOC S, ZUO P, WANG X, et al. Parameter optimization of a biodegradable agricultural film manufactured with wheat straw fiber[J]. BioResources, 2022,17(2): 2331-2346). The specific steps are as follows:

[0084] Wheat straw was processed into a semi-finished product with an average length of 132 mm and a freeness of 83% using a shredder (shredder feed rate 1000 kg / h, spindle speed 1800 r / min). The semi-finished product was soaked and washed to remove impurities and increase its moisture content. Then, the semi-finished product was processed into wheat straw fiber using a D200 fiber extraction machine via extrusion and bursting. The wheat straw fiber and unbleached KP pulp board were then soaked in clean water for at least 4 hours. Then, according to GB / T24325-2009 "Valley Beater Method for Pulp", the prepared wheat straw fiber and KP fiber were placed in a Valley beater for 30 minutes for debonding treatment, and then beaten to the required freeness (wheat straw pulp 55±5 °SR, unbleached KP pulp 45±2 °SR) for later use. Then, based on specific needs, wheat straw pulp and KP pulp were mixed at a ratio of 65:35 (both measured as oven-dry pulp), and 1.0% wet strength agent and 1.4% neutral sizing agent were added (both measured as oven-dry pulp). Finally, the basis weight of the wheat straw fiber base film was 60 g / m³. 2 By adjusting the parameters of the paper machine, the plastic film is pressed and dried to complete the preparation of WFM.

[0085] (2) Preparation of 2% (m / v) gelatin solution: Add gelatin to 2% (v / v) glacial acetic acid aqueous solution, place the solution in a constant temperature magnetic stirrer, stir at 400 rpm at 50°C until the gelatin is completely dissolved; then add glycerol as a plasticizer (the concentration of glycerol in the gelatin solution is 0.3%), and continue stirring for 30 min to prepare a uniform gelatin solution for later use;

[0086] To prepare a carbendazim solution: Add 0.08 g of carbendazim to a 2% (v / v) glacial acetic acid aqueous solution and stir for 30 min.

[0087] The prepared gelatin solution was mixed with the carbendazim solution and stirred again for 30 min to ensure that the two solutions were fully mixed, thus preparing the carbendazim / gelatin solution. The above mixture was coated onto a WFM with a size of 20×35 cm with a wet film thickness of 20 μm to obtain a C-Gel-WFM sample with a drug loading of 0.1 g / m².

[0088] Example 2

[0089] A method for preparing a straw fiber-based antibacterial mulch film with temperature and humidity responsive properties.

[0090] The difference from Example 1 is that the amount of carbendazim added in step (2) was modified to 0.04 g, and a C-Gel-WFM sample with a drug loading of 0.05 g / m² was finally prepared. Other preparation processes and conditions were the same as in Example 1.

[0091] Example 3

[0092] A method for preparing a straw fiber-based antibacterial mulch film with temperature and humidity responsive properties.

[0093] The difference from Example 1 is that the amount of carbendazim added in step (2) was modified to 0.12 g, and a C-Gel-WFM sample with a drug loading of 0.15 g / m² was finally prepared. Other preparation processes and conditions were the same as in Example 1.

[0094] Example 4

[0095] A method for preparing a straw fiber-based antibacterial mulch film with temperature and humidity responsive properties.

[0096] The difference from Example 1 is that it also includes step (3): using a laboratory coater and an OSP coating bar with a wet film thickness of 20 μm, the palm wax emulsion is coated on the C-Gel-WFM sample with different wet film thicknesses, thereby preparing CW-C-Gel-WFM samples with different wet film thicknesses.

[0097] Example 5

[0098] A method for preparing a straw fiber-based antibacterial mulch film with temperature and humidity responsive properties.

[0099] The difference from Example 4 is that the wet film thickness in step (3) is replaced with 10 μm. Other preparation processes and conditions are the same as in Example 1.

[0100] Example 6

[0101] A method for preparing a straw fiber-based antibacterial mulch film with temperature and humidity responsive properties.

[0102] The difference from Example 4 is that the wet film thickness in step (3) is replaced with 30 μm. Other preparation processes and conditions are the same as in Example 1.

[0103] Comparative Example 1

[0104] The difference from Example 1 is that no carbendazim is added, but the other preparation process and conditions are the same as in Example 1.

[0105] Effect verification:

[0106] I. The following performance tests were performed on the C-Gel-WFM samples with different drug loadings prepared in Examples 1-3 and the sample prepared in Comparative Example 1 without the addition of carbendazim:

[0107] (1) Dry tensile strength

[0108] Figure 1A bar chart showing the effect of different drug loadings on dry tensile strength. From Figure 1 As can be seen, higher drug loading has a significant impact on dry tensile strength. With increasing drug loading, the dry tensile strength of C-Gel-WFM exhibits a trend of first increasing and then decreasing. When the drug loading is below 0.1 g / m², the dry tensile strength increases with increasing drug loading; however, when the drug loading exceeds 0.1 g / m², the dry tensile strength decreases with further increases in drug loading. The maximum value of 1.49 kN / m is reached at a drug loading of 0.1 g / m². This is because a certain amount of carbendazim interacts with gelatin molecules, such as through hydrogen bonds or other weak interactions. This interaction acts as a cross-linking agent, making the bonds between gelatin molecules tighter, thereby increasing the dry tensile strength.

[0109] (2) Elongation at break

[0110] Figure 2 The bar chart shows the effect of different drug loadings on elongation at break. As can be seen from the figure, a higher drug loading has a significant impact on elongation at break. With increasing drug loading, the elongation at break of C-Gel-WFM initially increases and then decreases. When the drug loading is below 0.05 g / m², the elongation at break increases with increasing drug loading; when the drug loading exceeds 0.05 g / m², the elongation at break begins to decrease with increasing drug loading. The maximum value occurs at a drug loading of 0.05 g / m², where the elongation at break reaches 2.61%.

[0111] (3) Wet tensile strength

[0112] Figure 3 The bar chart shows the effect of different drug loading on wet tensile strength.

[0113] The results showed that the drug loading significantly affected the wet tensile strength. With increasing drug loading, the wet tensile strength of C-Gel-WFM exhibited a trend of first increasing and then decreasing. When the drug loading was below 0.1 g / m², the wet tensile strength increased with increasing drug loading; however, when the drug loading exceeded 0.1 g / m², the wet tensile strength decreased with further increases in drug loading. The peak wet tensile strength was reached at a drug loading of 0.1 g / m², with a value of 0.7 kN / m. This is because carbendazim acts as a cross-linking agent in the membrane, strengthening the bonds between gelatin molecules. When the gelatin membrane is subjected to tensile force, this strengthened bond helps to more effectively transfer stress, allowing the membrane to withstand a certain amount of tension even in humid environments, thereby improving the wet tensile strength.

[0114] (4) SEM analysis

[0115] Figure 4The image shows the microstructure of the C-Gel-WFM sample prepared in Example 1, where a) is a 50x electron microscope image and b) is a 500x electron microscope image. As can be seen from the image, the C-Gel coating not only effectively fills the pores between fibers, but also forms a uniform coating on the fiber surface, which significantly reduces the surface roughness of the material.

[0116] (5) FTIR spectral analysis

[0117] Figure 5 The images show the FT-IR spectra of wheat straw fiber membrane, gelatin / carbendazim, and carbendazim / gelatin / straw fiber membrane from Example 1. The images show that the straw fiber base membrane exhibits high FT-IR spectra at 3333 cm⁻¹. -1 An absorption peak for the stretching vibration of -OH appears at 2915 cm⁻¹. -1 Asymmetric stretching vibrations of CH2- appear at 1424 cm⁻¹. -1 Shear vibrations and rocking vibrations of CH2- were observed at 1159 cm. -1 An absorption peak for the COC asymmetric stretching vibration of the pyranose ring appears at 1030 cm⁻¹. -1 Absorption peaks appear at 896 cm⁻¹ for the vibration of the hydroxyl group and the CO bond on the pyranose ring. -1 The characteristic absorption peak of the cellulose pyran ring appears at 3325 cm⁻¹, while that of gelatin / carbendazim is at 3325 cm⁻¹. -1 An absorption peak for the stretching vibration of the amino group (-NH-) in the carbendazim molecule was observed at 2950 cm⁻¹. -1 2881cm -1 An absorption peak for the stretching vibration of -CH3 appears at 1646 cm⁻¹. -1 An absorption peak for the stretching vibration of C=O (amide I) appears at 1635 cm⁻¹. -1 An absorption peak for the C=N stretching vibration of the benzimidazole ring appears at 1549 cm⁻¹. -1 An absorption peak appears at 1241 cm⁻¹, resulting from the coupling of the bending vibration of NH₄⁺ and the stretching vibration of CN₂ (amide II). -1 A combined vibrational absorption peak of in-plane bending vibration of NH and stretching vibration of CN appeared at 3325 cm⁻¹. Infrared spectroscopy analysis of the carbendazim / gelatin / straw fiber membrane showed that the composite membrane exhibited an absorption peak at 3325 cm⁻¹. -1 2950cm -1 2881cm -1 1646 cm -1 1635 cm -1 1549 cm -1 1241 cm -1 The characteristic absorption peak of gelatin / carbendazim appears at 3333 cm⁻¹. -1 2915 cm-1 1424 cm -1 1159 cm -1 896 cm -1 The presence of characteristic absorption peaks of wheat straw fiber indicates that gelatin / carbendazim was successfully coated onto the wheat straw fiber base film.

[0118] (6) Drug release behavior analysis

[0119] 1) Carbendazim standard curve

[0120] Figure 6 For example, a standard curve of carbendazim. Figure 6 As shown, the regression equation for the curve is Y = 0.0709x + 0.0217, and the correlation coefficient R0 is... 2 =0.9932. The carbendazim content was determined according to the method of "GB / T 5009.188-2003 Determination of methyl thiophanate and carbendazim in vegetables and fruits". A standard curve was plotted with carbendazim concentration as the abscissa and absorbance as the ordinate.

[0121] 2) Drug release behavior

[0122] Figure 7 The graphs show the effects of temperature and drug loading on drug release, where a) is the drug release curve at 20℃, b) is the drug release curve at 30℃, c) is the drug release curve at 40℃, and d) is the drug release curve at 0.05 g / m³. 2 The drug release curve, e), is 0.1 g / m³. 2 The drug release curve (f) is 0.15 g / m. 2 Drug release curves. As shown in the figures, the release of carbendazim from C-Gel-WFM mainly includes two stages: a burst release stage and a sustained release stage. Under constant temperature conditions, the effect of drug loading on drug release from C-Gel-WFM is shown in Figures a)-c). The higher the drug loading, the longer the sustained release time. When the drug loading is 0.15 g / m³... 2 At that time, the longest sustained-release time was 96 h, 120 h, and 156 h, relative to a drug loading of 0.05 g / m³. 2The release time was extended by 72–84 h. When the drug loading remained constant, the effect of temperature on drug release from C-Gel-WFM is shown in Figures d)–f). Higher temperatures resulted in faster release rates and shorter sustained-release times. This is because, in the initial burst release phase, the high solubility of carbendazim / gelatin near the membrane surface leads to the rapid release of adsorbed and retained carbendazim molecules. When the concentration of carbendazim in the solution reaches a certain level, this increase in concentration, in turn, inhibits further release of carbendazim, slowing the release rate and leading to a sustained-release phase. At a constant temperature, the increased drug loading of C-Gel-WFM results in a longer sustained-release phase, thus extending the release time. When the drug loading remained constant, due to the unique temperature-sensitive properties of gelatin, at low temperatures, the hydrogen bonds between gelatin molecular chains are stronger, and the molecular chains cross-link to form a stable three-dimensional network structure, causing the gelatin solution to transform into a gel state. As the temperature increases, the thermal motion of molecules intensifies, hydrogen bonds and hydrophobic interactions are disrupted, the three-dimensional network structure gradually disintegrates, and the gel transforms back into a sol state. This phase transition process leads to an increase in the sustained release of carbendazim as the temperature rises. The phase transition temperature of gelatin is approximately between 35 and 40°C. Therefore, compared to 20°C, the sustained release rate of carbendazim increases more slowly at 30°C, while at 40°C the sustained release rate increases rapidly and the sustained release time decreases.

[0123] II. The following performance tests were performed on the CW-C-Gel-WFM samples with different barrier layer thicknesses prepared in Examples 4-6:

[0124] (1) Mechanical property analysis

[0125] Figure 8 The bar chart shows the effect of different wet film thicknesses on the dry tensile strength. As shown, wet film thickness has a significant impact on the dry tensile strength of CW-C-Gel-WFM. With increasing coating thickness, the dry tensile strength of the composite film exhibits a trend of first decreasing, then increasing, and then decreasing again. When the film thickness is 10 μm, the dry tensile strength decreases significantly with increasing wet film thickness. When the wet film thickness is 20 μm, the dry tensile strength increases significantly with increasing wet film thickness. When the wet film thickness exceeds 20 μm, the dry tensile strength decreases significantly with increasing wet film thickness. The maximum dry tensile strength occurs on the uncoated original film, with a value of 1.49 kN / m. This is because the overall mechanical properties of WFM itself decrease after repeated coating with the coating machine, thus affecting the dry tensile strength of the composite film. Palm wax molecules can fill the gaps between gelatin molecules. When the gelatin film is stretched, palm wax acts like a "support skeleton," helping to disperse some of the external force, thereby improving the dry tensile strength. At the same time, the presence of palm wax makes the binding between gelatin molecules tighter. This tight structure can withstand greater tensile force, thereby improving the tensile strength of the gelatin film.

[0126] (2) Wet tensile strength

[0127] Figure 9 The bar chart shows the effect of different wet film thicknesses on wet tensile strength. As shown, wet film thickness has a significant impact on the wet tensile strength of CW-C-Gel-WFM film. The wet tensile strength of CW-C-Gel-WFM exhibits a trend of first decreasing, then increasing, and finally decreasing again with increasing coating thickness. When the film thickness is 10 μm, the wet tensile strength decreases significantly; when the film thickness is 20 μm, the wet tensile strength increases significantly; and when the film thickness is 30 μm, the wet tensile strength decreases significantly. This is because palm wax molecules effectively fill the gaps between gelatin molecules. When the gelatin film is stretched, palm wax acts like a "supporting skeleton," helping to disperse some of the external force, thereby increasing the wet tensile strength. Simultaneously, the presence of palm wax strengthens the bonding between gelatin molecules, forming a more compact structure that can withstand greater tensile forces, thus enhancing the tensile strength of the film.

[0128] (3) Analysis of sizing degree

[0129] Figure 10 The bar chart shows the effect of different wet film thicknesses on the sizing degree. As shown, wet film thickness has a significant impact on the sizing degree of CW-C-Gel-WFM. With increasing coating thickness, the sizing degree of CW-C-Gel-WFM exhibits a significant upward trend. The sizing degree reaches its maximum value of 220 s when the wet film thickness reaches 30 μm. This is because palm wax has strong hydrophobicity. On the surface and inside the gelatin film coated with palm wax, it forms a hydrophobic barrier, effectively preventing liquid penetration and thus enhancing the sizing degree of the gelatin film.

[0130] (4) SEM analysis

[0131] Figure 11 The images show the microstructure of the CW-C-Gel-WFM prepared in Example 4, where a) is a 50x electron microscope image and b) is a 500x electron microscope image. As can be seen from the images, when palm wax is uniformly coated on the surface of the C-Gel-WFM, it forms a uniform and continuous protective layer on the membrane surface. This protective layer effectively reduces the number and size of pores, thereby enhancing the barrier properties of the membrane. The material surface becomes smoother, which further reduces porosity and pore size, thus improving the overall performance of the material.

[0132] (5) FTIR spectral analysis

[0133] Figure 12The images show the FTIR spectra of CW-C-Gel-WFM, C-Gel-WFM, and CW prepared in Example 4. As can be seen from the figures, palm wax exhibits a high FTIR spectrum at 2917 cm⁻¹. -1 An asymmetric stretching vibration absorption peak of -CH3 appears at 2849 cm⁻¹. -1 An absorption peak for the symmetric stretching vibration of -CH2- appears at 1734 cm⁻¹. -1 An absorption peak for the stretching vibration of C=O in the ester group (-COO-) appears at 1463 cm⁻¹. -1 Absorption peaks for the CH bending vibrations of methyl and methylene groups appear at 1352 cm⁻¹. -1 A symmetrical bending vibration absorption peak of -CH3 appears at 1252 cm⁻¹. -1 and 1173 cm -1 An absorption peak for the COC stretching vibration of the ester group appears at 720 cm⁻¹. -1 An in-plane rocking vibration absorption peak of the methylene group appears at 3325 cm⁻¹. C-Gel-WFM shows an absorption peak at 3325 cm⁻¹. -1 An absorption peak for the stretching vibration of the amino group (-NH-) in the carbendazim molecule appears at 1635 cm⁻¹. -1 An absorption peak for the C=N stretching vibration of the benzimidazole ring appears at 1549 cm⁻¹. -1 An absorption peak appears at 1030 cm⁻¹, resulting from the coupling of the bending vibration of NH₄⁺ and the stretching vibration of CN₂ (amide II). -1 Absorption peaks appear at 896 cm⁻¹ for the vibration of the hydroxyl group and the CO bond on the pyranose ring. -1 The characteristic absorption peak of the cellulose pyran ring appears at 2917 cm⁻¹. CW-C-Gel-WFM membrane infrared spectroscopy analysis shows that the characteristic absorption peak of the cellulose pyran ring appears at 2917 cm⁻¹. -1 2849 cm -1 1734 cm -1 1463 cm -1 1352 cm -1 1252 cm -1 1173 cm -1 720 cm -1 The characteristic peak of palm wax appears at 3325 cm⁻¹. -1 1635 cm -1 1549 cm -1 1030 cm -1 896 cm -1 The presence of characteristic peaks in the C-Gel-WFM membrane indicates that CW was successfully loaded onto the C-Gel-WFM membrane to prepare the CW-C-Gel-WFM membrane.

[0134] (6) Drug release behavior analysis

[0135] Figure 13 The graphs show the effects of different temperatures and wet film thicknesses on drug release. Under constant temperature conditions, the drug release rate slows down and the sustained-release time prolongs with increasing palm wax wet film thickness. The longest sustained-release times are 96, 120, and 168 h when the wet film thickness is 30 μm, which is 48–60 h longer than C-Gel-WFM. When the wet film thickness is constant, the release rate increases with increasing temperature, while the release time decreases. This is due to the excellent hydrophobicity of palm wax. From a chemical structure perspective, palm wax is mainly composed of wax esters, which contain long-chain fatty acids and long-chain alcohols. These long-chain structures have significant hydrophobic properties, effectively preventing water molecule penetration and forming a protective layer similar to a "waterproof barrier," making it difficult for water molecules to penetrate the interactions between long-chain molecules and enter the material's interior. Physically, palm wax forms a continuous waxy film on the surface of the mulch film. When palm wax is applied to an object's surface, its molecules are tightly packed, filling the tiny pores on the surface. This tight molecular arrangement greatly hinders the permeation channels of water molecules, thus delaying the dissolution of the drug.

[0136] III. To evaluate the antibacterial efficacy of the antibacterial mulch film, this invention selected *Fusarium solani*, the main pathogen of soybean root rot, as the test subject. Pot experiments were conducted to investigate the effects of different mulch film treatments on soybean disease index, plant height, plant weight, and root development. This not only verifies the antibacterial properties of the mulch film but also assesses its potential promoting effect on soybean growth and health.

[0137] This potted plant experiment used Heinong 84 soybean seeds, which were disinfected with a 10% sodium hypochlorite solution. The potting mix used was a mixed substrate prepared from native soil, substrate, peat moss, and perlite in a mass ratio of 3:3:2:2. Before filling the pots, the potting mix was sterilized at 120℃ for 2 hours to ensure a sterile environment.

[0138] The experiment included six treatment groups: WFM, Gel-WFM (Comparative Example 1), C-Gel-WFM (Example 1), CW-C-Gel-WFM (Example 4), a carbendazim-only treatment group (0.04 g of carbendazim was added to 50 mL of 2% (v / v) glacial acetic acid aqueous solution; the carbendazim group was treated with 5 mL of solution), and bare land without mulch (CK). Each treatment group was replicated three times, with five soybean seeds planted in each replicate.

[0139] After soybean germination, precisely pipette a measured amount of diluted spore suspension and carefully drip it slowly into the soil around the roots of the soybean plants to ensure even distribution (10 mL per plant). After this, gently cover the spore suspension with a thin layer of soil to prevent evaporation or splashing. The spore suspension is prepared as follows: Inoculate Fusarium solani mycelium onto potato dextrose agar (PDA) medium and culture the strain for 7 days. Add 5 mL of sterile water to the culture plate using a pipette, then scrape the colonies from the plate into a sterile centrifuge tube using a sterile inoculation spatula. Add another 10 mL of sterile water to the tube, tighten the cap, shake well, and then shake thoroughly in a shaker to ensure the spores are uniform and do not separate into distinct layers. Filter the solution through gauze to prepare the spore suspension, and then dilute it to a concentration of 1×10⁻⁶ with physiological saline. 8 / mL.

[0140] Analysis of soybean growth and health status

[0141] Twenty days after inoculation, a single-factor completely randomized design was used to ensure data reliability. Evaluation indicators included disease index, soybean plant height, fresh soybean weight, and soybean root dry weight, which comprehensively reflect the growth and health status of soybeans. To statistically verify the differences between treatments, a multiple comparison method was used to analyze the experimental results. The root rot disease disease index was graded according to standard GB / T17980.88-2004, and the disease index and incidence rate of soybean root rot were calculated according to relevant formulas to investigate the disease occurrence.

[0142] Figure 14The image shows the growth of soybeans after different treatments. As shown, the soybean plant growth is ranked as follows: CW-C-GEL-WFM > C-GEL-WFM > Carbendazim > WFM > GEL-WFM > CK treatment group. Inoculation with the pathogen significantly inhibited seedling growth, resulting in a marked reduction in plant height. In the carbendazim-containing treatments, the soybeans in the CW-C-Gel-WFM, C-Gel-WFM, and carbendazim treatment groups showed significantly better growth than other groups because the release of carbendazim effectively reduced the incidence of root rot. The poor performance of the Gel-WFM group may be due to the fact that, under suitable environmental conditions, gelatin may have provided abundant nutrients for the pathogen, promoting its proliferation and increasing the risk of infection. Soybean growth in the CW-C-Gel-WFM and C-Gel-WFM groups was superior to that in the group treated with carbendazim alone. This is because mulching not only reduces soil heat loss and moisture evaporation but also provides a more stable and suitable growing environment for soybean plants, thereby promoting growth. Furthermore, mulching helps maintain soil aeration and structure, providing favorable conditions for root development and further enhancing the plant's disease resistance.

[0143] Figure 15 The figure shows the growth and development of soybeans after different treatments, where a) is the control (CK), b) is carbendazim, c) is WFM, d) is Gel-WFM, e) is C-Gel-WFM, and f) is CW-C-Gel-WFM. As shown, the soybeans in all five treatment groups were significantly better than the control group in key growth indicators such as plant height, fresh plant weight, and root dry weight. This result indicates that although all experiments were conducted in the same soil environment, different treatments had a significant impact on soybean growth, leading to differences in growth indicators. Specifically, these treatment groups, through mulching and the application of carbendazim, provided more favorable growth conditions for soybeans, such as improved soil moisture, temperature, and nutrient supply, thereby promoting the overall growth performance of the plants.

[0144] (1) Soybean plant height

[0145] Figure 16A bar chart showing the effect of different treatments on soybean plant height is provided. As shown in the figure, soybean plant height is ranked as follows: CW-C-GEL-WFM > C-GEL-WFM > Carbendazim > WFM > GEL-WFM > CK treatment group. Analysis of variance showed significant differences in soybean plant growth indicators between the experimental and control groups (P < 0.01). Further multiple comparison analysis indicated that the soybean plant height of the CW-C-GEL-WFM treatment was significantly different from all other treatment groups. Similarly, the soybean plant height of the C-GEL-WFM treatment also showed a significant difference compared to other groups. In contrast, there was no significant difference in soybean plant height between the GEL-WFM and WFM treatment groups. Furthermore, the treatment group using carbendazim alone also showed a significant difference in soybean plant height compared to other groups. Soybean seedlings are susceptible to root rot. The CW-C-GEL-WFM and C-GEL-WFM treatments, due to their slow-release properties, allow for the continuous release of carbendazim to the pathogen's location, effectively protecting soybeans from infection and promoting plant growth. Therefore, these two groups produced the tallest soybean plants. The carbendazim-only treatment, with its early direct release of the fungicide, also significantly inhibited root rot, and the reduced incidence of root rot also contributed to limited growth. Compared to the control group, the WFM and GEL-WFM treatments showed better growth due to the more stable and suitable growing environment provided by the mulch film.

[0146] (2) Fresh soybean plant weight

[0147] Figure 17 The bar chart shows the effect of different treatments on soybean fresh plant weight. Soybean fresh plant weight: CW-C-GEL-WFM > C-GEL-WFM > Carbendazim > WFM > GEL-WFM > CK treatment group. Analysis of variance showed significant differences in soybean growth indicators between the experimental and control groups (P<0.01). Further multiple comparison analysis showed that the soybean fresh plant weight of the CW-C-GEL-WFM group was significantly different from all other treatment groups. Similarly, the soybean fresh plant weight of the C-GEL-WFM group also showed a significant difference from other groups. In contrast, there were no significant differences in soybean fresh plant weight between the GEL-WFM and WFM treatment groups and the CK group. Furthermore, the treatment group using carbendazim alone also showed a significant difference in soybean fresh plant weight compared to other groups.

[0148] During the seedling stage, soybean plants are highly susceptible to root rot and easily infected. However, soybean mulch treated with CW-C-GEL-WFM and C-GEL-WFM, due to its slow-release properties, can continuously release carbendazim to the sites where pathogens accumulate. This continuous release mechanism not only effectively prevents soybeans from being attacked by pathogens but also promotes overall plant growth, resulting in the highest possible fresh plant weight for both groups of soybeans. Furthermore, these treatments provide a more favorable growing environment for soybeans by suppressing weed growth, further promoting soybean growth and significantly increasing fresh plant weight.

[0149] (3) Dry weight of soybean roots

[0150] Figure 18 The bar chart shows the effect of different treatments on soybean root dry weight. As shown in the figure, the soybean root dry weight is as follows: CW-C-GEL-WFM group > C-GEL-WFM group > Carbendazim treatment group > WFM group > GEL-WFM group > CK group. Analysis of variance showed significant differences in soybean growth indicators between the experimental and control groups (P<0.01). Further multiple comparison analysis showed that the soybean root dry weight of the CW-C-GEL-WFM treatment was significantly different from all other treatment groups. Similarly, the soybean root dry weight of the C-GEL-WFM treatment also showed a significant difference from other groups. In contrast, there was no significant difference in soybean root dry weight between the GEL-WFM treatment group, the WFM treatment group, and the CK group.

[0151] During the soybean seedling stage, plants are highly susceptible to root rot and easily infected. However, soybean mulch treated with CW-C-GEL-WFM and C-GEL-WFM, utilizing the slow-release properties of these films, can continuously release carbendazim into areas where pathogens accumulate. This sustained release mechanism prolongs the effective action time of carbendazim, reduces the incidence of root rot, and promotes soybean root growth, resulting in the highest root dry weight in both groups of soybeans. Furthermore, these treatments create a more favorable growth environment for soybeans by suppressing weed growth, further promoting soybean growth and significantly increasing soybean root dry weight.

[0152] Figure 19The bar chart shows the effects of different treatments on soybean roots. As shown, the comparison of root development among the five treatment groups affected by soybean root rot reveals significant differences between them. The CW-C-Gel-WFM treatment group showed the best root development and the most advanced root system, followed by the C-Gel-WFM treatment group. Both groups exhibited healthy root characteristics without obvious signs of disease. Although the carbendazim treatment group did not use slow-release technology, its early direct application of the fungicide also showed good inhibitory effects on root rot, with good root growth. The soybean roots in the CK, WFM, and Gel-WFM groups clearly showed brown patches, a typical characteristic of root rot, indicating that soybeans are highly susceptible to root rot without appropriate treatment. The appropriately treated groups, especially the CW-C-Gel-WFM and C-Gel-WFM treatment groups, not only effectively prevented root rot but also promoted healthy root growth, significantly improving soybean growth quality and yield.

[0153] (1) Soybean root rot disease severity index

[0154] Figure 20 The bar chart shows the effect of different treatments on the soybean root rot index. As shown in the figure, the soybean root rot index is as follows: CW-C-GEL-WFM < C-GEL-WFM < Carbendazim treatment < WFM < GEL-WFM < CK treatment group.

[0155] Analysis of variance showed that there were no significant differences among soybean plants in the CW-C-GEL-WFM, C-GEL-WFM, and carbendazim treatment groups, but there were highly significant differences compared with the WFM, GEL-WFM, and CK groups. The slow-release technology used in the CW-C-GEL-WFM and C-GEL-WFM groups was comparable to, or even better than, carbendazim treatment alone. This is because, in the CW-C-GEL-WFM and C-GEL-WFM groups, carbendazim was continuously released to the diseased area through physical diffusion and dissolution of the adhesive, thereby effectively reducing the disease index of soybean root rot.

[0156] In contrast, the carbendazim treatment group, which used direct root drenching, had its efficacy primarily exerted in the early stages, resulting in a slightly higher soybean root rot disease index compared to the CW-C-GEL-WFM and C-GEL-WFM groups. While the WFM and GEL-WFM groups did not receive carbendazim, the mulch provided more favorable growing conditions for soybeans, thus reducing the soybean root rot disease index. The GEL-WFM group, due to the gelatin potentially providing abundant nutrients for pathogens and promoting their reproduction, increased the risk of plant infection.

[0157] Soybean plants in the CK treatment had the highest root rot disease index because no fungicide was applied. These findings highlight the important role of appropriate agricultural management practices, such as slow-release pesticides and mulching, in controlling soybean root rot and promoting healthy plant growth.

[0158] (2) Incidence of soybean root rot

[0159] Figure 21 The bar chart shows the effect of different treatments on the incidence of soybean root rot. As shown in the figure, the incidence of soybean root rot was best in the C-GEL-WFM group, followed by the CW-C-GEL-WFM group and the carbendazim treatment group, which were comparable. Then came the WFM group and the GEL-WFM group, while the control group (CK) performed the worst.

[0160] Analysis of variance further confirmed that there were no significant differences between soybean plants in the CW-C-GEL-WFM and C-GEL-WFM groups, but the differences were extremely significant compared with the WFM, GEL-WFM, and CK groups. This demonstrates that the slow-release technology used in the CW-C-GEL-WFM and C-GEL-WFM groups continuously releases the pathogen to the affected area through physical diffusion and the dissolving effect of the adhesive, thereby effectively reducing the incidence of soybean root rot.

[0161] In contrast, the carbendazim treatment group, which used direct root irrigation, had its efficacy mainly exerted in the early stages, resulting in a slightly higher incidence of soybean root rot compared to the CW-C-GEL-WFM and C-GEL-WFM groups.

[0162] As for the soybean plants in the control group (CK) and the WFM and GEL-WFM treatments, the incidence of soybean root rot was higher because no fungicides were applied. These findings highlight the crucial role of appropriate agricultural management practices, such as the application of slow-release pesticides and mulching, in controlling soybean root rot and promoting healthy plant growth.

[0163] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A straw fiber-based antibacterial mulch film with temperature and humidity responsive properties, characterized in that, From bottom to top, it includes a bottom membrane layer and a sustained-release layer; or, From bottom to top, it includes a bottom membrane layer, a sustained-release layer, and a barrier layer; The sustained-release layer is obtained by coating the base film layer with a mixed solution of acetic acid, bactericide, gelatin and plasticizer; the bactericide is carbendazim; the plasticizer is glycerin; and the thickness of the sustained-release layer is 14.16 μm–30 μm. The barrier layer is obtained by coating the surface of the slow-release layer with palm wax emulsion; the thickness of the barrier layer is 10μm-30μm. The method for preparing the straw fiber-based antibacterial mulch film with temperature and humidity responsive properties includes the following steps: Gelatin, bactericide, and plasticizer are added to an aqueous acetic acid solution and stirred until homogeneous to obtain a mixed solution; The mixed solution is coated onto the base film layer using bar coating technology to form a slow-release layer, thereby obtaining a straw fiber-based antibacterial mulch film with temperature and humidity responsive properties, comprising a base film layer and a slow-release layer. Palm wax emulsion is coated onto the slow-release layer to form a barrier layer, thereby obtaining a straw fiber-based antibacterial mulch film with temperature and humidity responsive properties, consisting of a base film layer, a slow-release layer, and a barrier layer.

2. The straw fiber-based antibacterial mulch film with temperature and humidity responsiveness according to claim 1, characterized in that, The bottom membrane layer is a straw fiber base membrane.

3. A method for preparing a straw fiber-based antibacterial mulch film with temperature and humidity responsive properties as described in any one of claims 1-2, characterized in that, Includes the following steps: Gelatin, bactericide, and plasticizer are added to an aqueous acetic acid solution and stirred until homogeneous to obtain a mixed solution; The mixed solution is coated onto the base film layer using bar coating technology to form a slow-release layer, thereby obtaining a straw fiber-based antibacterial mulch film with temperature and humidity responsive properties, comprising a base film layer and a slow-release layer. Palm wax emulsion is coated onto the slow-release layer to form a barrier layer, thereby obtaining a straw fiber-based antibacterial mulch film with temperature and humidity responsive properties, consisting of a base film layer, a slow-release layer, and a barrier layer.

4. The method for preparing a straw fiber-based antibacterial mulch film with temperature and humidity responsiveness according to claim 3, characterized in that, The preparation process of the straw fiber-based antibacterial mulch film with temperature and humidity responsive properties is as follows: (1) Dissolve gelatin in an aqueous acetic acid solution and stir until the gelatin is evenly dissolved. Then add plasticizer and continue stirring to obtain solution 1. (2) Stir the bactericide and acetic acid aqueous solution evenly to obtain solution 2; (3) Mix the solution 1 and the solution 2 evenly to obtain solution 3; (4) The solution 3 is coated onto the base film layer using wire rod coating technology to obtain C-Gel-WFM; (5) The palm wax emulsion is coated onto the surface of the C-Gel-WFM using bar coating technology to obtain CW-C-Gel-WFM, which is the straw fiber-based antibacterial mulch film with temperature and humidity response properties.

5. The method for preparing a straw fiber-based antibacterial mulch film with temperature and humidity responsiveness according to claim 4, characterized in that, The loading of the bactericide in the C-Gel-WFM is 0.05-0.15 g / m³. 2 .

6. The method for preparing a straw fiber-based antibacterial mulch film with temperature and humidity responsiveness according to claim 4, characterized in that, In the solution 1, the concentration of the gelatin is 1.78%–2.24%, and the concentration of the plasticizer is 0.26%–0.35%.

7. The method for preparing a straw fiber-based antibacterial mulch film with temperature and humidity responsiveness according to claim 6, characterized in that, In solution 1, the concentration of the gelatin is 2%.

8. The method for preparing a straw fiber-based antibacterial mulch film with temperature and humidity responsiveness according to claim 4, characterized in that, The concentration of the acetic acid aqueous solution is 2%.

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