Insect pheromone ink, insect pheromone lure and preparation, application and recovery of insect pheromone ink and insect pheromone lure

Abstract

The invention relates to the technical field of agricultural pest control, in particular to insect pheromone printing ink, an insect pheromone lure and preparation, application and recycling of the insect pheromone printing ink and the insect pheromone lure. The insect pheromone ink comprises a thermoplastic biodegradable high polymer material, an alcohol plasticizer, a graded volatile organic solvent and insect pheromone, the material can further comprise a functional modified material. The functional modified material comprises lignosulfonate and metal salt. The insect pheromone ink provided by the invention can be prepared into an insect pheromone lure through 3D printing, the preparation process is simple, the cost is low, meanwhile, the entrapment efficiency of pheromone in the insect pheromone lure is high, the field release duration is long, and the insect pheromone lure is degradable, recyclable and environment-friendly.

Description

Technical Field

[0001] The invention relates to the technical field of agricultural pest control, and in particular to an insect pheromone ink, an insect pheromone attractant core, and preparation, application and recovery thereof. Background Art

[0002] Agriculture, as the cornerstone of the global economy and human survival, is facing the dual challenges of climate change and population growth. At the same time, the monoculture model has contributed to the spread of pests and pathogens, resulting in an annual loss of 26% to 80% in agricultural production. Traditional pest management strategies rely on chemical pesticides, which can effectively control pests in the short term, but their negative impact on the environment and human health is becoming increasingly obvious. The widespread use of pesticides not only pollutes soil and water sources, destroys biodiversity, but also increases pest resistance.

[0003] Insect pheromones are chemicals produced by insects themselves, usually released by female insects to attract males of the opposite sex for mating. As an environmentally friendly alternative to traditional pesticides, insect pheromones have played a significant role in the integrated pest management (IPM) strategy, and their applications mainly include monitoring pest populations, trapping, and mating disruption. This method is not only highly species-specific, ensuring that it only works on specific pests, but also has the characteristic of achieving efficient control with a trace amount, greatly reducing the burden on the environment.

[0004] Most pheromone components are volatile substances with unstable chemical properties. Unless they are formulated in a controlled release device, they will evaporate quickly. The current carriers used to extend the duration of pheromones (such as rubber, polyethylene plastic, etc.) usually use solvents to physically combine pheromones with materials, which have shortcomings such as short duration and poor degradability. In recent years, microcapsules, nanoparticles and metal-organic frameworks for sustained release of pheromones have continued to emerge. Although these new carriers have shown significant advantages in the controlled release of pheromones, they generally have problems such as low pheromone loading, short field release duration, complex preparation process and high cost. Therefore, there is an urgent need for an efficient, environmentally friendly, industrially producible and economical pheromone carrier. Summary of the invention

[0005] In view of this, the object of the present invention is to provide an insect pheromone ink, an insect pheromone attractant core, and preparation, application and recycling thereof. The insect pheromone ink provided by the present invention can be made into an insect pheromone attractant core through 3D printing, and the preparation process is simple and the cost is low. At the same time, the pheromone encapsulation rate in the insect pheromone attractant core is high, the field release duration is long, and it is degradable and recyclable, and is environmentally friendly.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions: The present invention provides an insect pheromone ink, comprising the following components: a thermoplastic biodegradable polymer material, an alcohol plasticizer, a graded volatile organic solvent and an insect pheromone; The fractionated volatile organic solvents include at least one high volatility organic solvent and at least one low volatility organic solvent; The mass content of the thermoplastic biodegradable polymer material in the insect pheromone ink is 12-16%; The mass of the alcohol plasticizer is 0.2-3% of the mass of the thermoplastic biodegradable polymer material; The mass of the insect pheromone is 0.01-15% of the mass of the thermoplastic biodegradable polymer material.

[0007] Preferably, it further comprises an aqueous solution of a functional material; the functional material comprises lignin sulfonate and a metal salt; the concentration of the lignin sulfonate and the metal salt in the aqueous solution of the functional material is independently 0.25-1 g / mL; The mass of the lignin sulfonate is 0.02-0.5% of the mass of the thermoplastic biodegradable polymer material; the mass of the metal salt is 0.1-2.5% of the mass of the thermoplastic biodegradable polymer material; the metal salt includes one or more of trivalent iron salt, aluminum salt and divalent copper salt.

[0008] Preferably, the lignin sulfonate comprises sodium lignin sulfonate and / or calcium lignin sulfonate; The ferric iron salt includes ferric chloride; the aluminum salt includes aluminum chloride; and the divalent copper salt includes copper chloride.

[0009] Preferably, the thermoplastic biodegradable polymer material includes one or more of polylactic acid, polycaprolactone, polyhydroxybutyrate and cellulose acetate.

[0010] Preferably, the alcohol plasticizer includes one or more of polyethylene glycol, glycerol and polypropylene alcohol.

[0011] Preferably, the high volatility organic solvent includes at least one of acetone, dichloromethane and ethanol; and the low volatility organic solvent includes at least one of N,N-dimethylformamide and dimethyl sulfoxide.

[0012] The present invention provides an insect pheromone attractant core, which is prepared by 3D printing of the insect pheromone ink described in the above scheme.

[0013] The present invention provides a method for preparing the insect pheromone attractant core described in the above scheme, comprising the following steps: 3D printing the insect pheromone ink described in the above scheme, wherein the layer height of the 3D printing is 0.8-1.5 mm, the filling density is 70-100%, and the printing speed is 10-20 mm / s.

[0014] The present invention provides the use of the insect pheromone attractant core described in the above scheme in pest control.

[0015] The present invention provides a method for recycling and reusing the insect pheromone attractant core described in the above scheme, comprising the following steps: mixing the powder of the recycled insect pheromone attractant core and the insect pheromone with graded volatile organic solvents to obtain drug-loaded ink, which is used again for 3D printing.

[0016] The invention provides an insect pheromone ink, comprising the following components: a thermoplastic biodegradable polymer material, an alcohol plasticizer, a graded volatile organic solvent and an insect pheromone; the graded volatile organic solvent comprises at least one high-volatile organic solvent and at least one low-volatile organic solvent; the mass content of the thermoplastic biodegradable polymer material in the insect pheromone ink is 12-16%; the mass of the alcohol plasticizer is 0.2-3% of the mass of the thermoplastic biodegradable polymer material; the mass of the insect pheromone is 0.01-15% of the mass of the thermoplastic biodegradable polymer material.

[0017] The ink of the present invention uses thermoplastic biodegradable polymer materials as basic materials, and the insect pheromone attractant core made after 3D printing has good degradation performance and is environmentally friendly; the insect pheromone is dissolved in the ink, and the content of the insect pheromone can be adjusted according to actual needs, avoiding the defect of low insect pheromone loading in the traditional loading method; in addition, after the ink provided by the present invention is printed, the insect pheromone will be evenly distributed between the cross-linked networks of the thermoplastic biodegradable polymer materials, achieving a sustained release effect, and the release duration in the field is long. The present invention selects graded volatile organic solvents. At room temperature, the high-volatile organic solvent helps the ink to dry quickly at room temperature, thereby maintaining the molding ability during the printing process, while the residual low-volatile organic solvent helps to maintain the fluidity of the ink and ensure the smoothness of the printing process.

[0018] Furthermore, the insect pheromone ink provided by the present invention also includes a functional modification material; the functional modification material includes lignin sulfonate and metal salt. Lignin has the functions of blocking ultraviolet rays, anti-aging and flame retardancy. The present invention introduces lignin sulfonate and metal ions to enhance the anti-ultraviolet ability and cross-linking effect of the ink after printing, so as to improve the stability and applicability of the 3D printed insect pheromone lure.

[0019] The present invention also provides a method for recycling the insect pheromone attractant core, thereby realizing efficient and rapid reuse of the attractant core. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the preparation process of the insect pheromone ink of Example 2; Figure 2 Photos of extrusion molding for CP and CP-SL-Fe inks; Figure 3 (a) Viscosity of CP and CP-SL-Fe inks as a function of shear rate and (b) storage modulus (G′) and loss modulus (G″) as a function of oscillation stress. Figure 4 The morphology of CP and CP-SL-Fe cores, where (a, c) are sample appearance photos and (b, d) are three-dimensional super-depth-of-field photos; Figure 5 Scanning electron microscope images of CP (a, b) and CP-SL-Fe decoy core (c, d); Figure 6 This is the iron element spectrum of the CP-SL-Fe core; Figure 7 (a) FTIR spectra of CP core, CP-SL-Fe core and CP-SL core modified with only lignin, (b) XRD patterns of CP core, CP-SL core and CP-SL-Fe core, (c) XPS scans of CP core and CP-SL-Fe core, (d) O1s XPS spectrum of CP core, (e) O1s XPS spectrum of CP-SL-Fe core; Figure 8 (a) TGA thermogravimetric curves of CP-K, CP, and CP-SL-Fe lures, (b) stress-strain curves of CP and CP-SL-Fe lures, (c) UV-visible diffuse reflectance of CP and CP-SL-Fe lures, (d) water contact angles of CP and CP-SL-Fe lures, (e) soil degradation weight loss rates of CP lures, CP-SL-Fe lures, and commercial rubber plug lures (CK), (f) soil degradation experimental photos of CP lures, CP-SL-Fe lures, and commercial rubber plug lures; Fig. 9 (a) Laboratory release curves of CP and CP-SL-Fe lures, (b) Field trapping photos of 3D printed lures, (c) Average weekly field captures of CP lures, CP-SL-Fe lures and commercial rubber plug lures, (d) Cumulative field captures of CP lures, CP-SL-Fe lures and commercial rubber plug lures (CK) (6 weeks); Fig.10 The drug release kinetics model analysis results of CP core and CP-SL-Fe core; Fig.11(a) Green processing roadmap, (b) Recycling experimental photos, (c, d) Recycling ink printing smoothness and plasticity photos, (e) SEM morphology of rCP-SL-Fe. (f) EDS spectrum of iron element of rCP-SL-Fe core, (g) FTIR spectrum of rCP-SL-Fe core, (h) Encapsulation efficiency comparison of CP-SL-Fe and rCP-SL-Fe core, (i) Stress-strain comparison of CP-SL-Fe and rCP-SL-Fe core. DETAILED DESCRIPTION

[0021] The present invention provides an insect pheromone ink, comprising the following components: a thermoplastic biodegradable polymer material, an alcohol plasticizer, a graded volatile organic solvent and an insect pheromone; The fractionated volatile organic solvents include at least one high volatility organic solvent and at least one low volatility organic solvent; The mass content of the thermoplastic biodegradable polymer material in the insect pheromone ink is 12-16%; The mass of the alcohol plasticizer is 0.2-3% of the mass of the thermoplastic biodegradable polymer material; The mass of the insect pheromone is 0.01-15% of the mass of the thermoplastic biodegradable polymer material.

[0022] In the present invention, unless otherwise specified, the raw materials used are commercially available products well known in the art.

[0023] The insect pheromone ink provided by the present invention includes a thermoplastic biodegradable polymer material. In the present invention, the thermoplastic biodegradable polymer material preferably includes one or more of polylactic acid, polycaprolactone, polyhydroxybutyrate and cellulose acetate, and more preferably cellulose acetate. In the present invention, the number average molecular weight (Mn) of the cellulose acetate is preferably 40,000-60,000 g / mol, and in a specific embodiment, it can be 40,000 g / mol, 45,000 g / mol, 50,000 g / mol, 55,000 g / mol or 60,000 g / mol; the acetyl content of the cellulose acetate is preferably 35-45 wt%. In the present invention, the mass content of the thermoplastic biodegradable polymer material in the insect pheromone ink is 12-16%, and in a specific embodiment, it can be 12%, 13%, 14%, 15% or 16%. In the present invention, the thermoplastic biodegradable polymer material is used as the base material of the insect pheromone ink.

[0024] The insect pheromone ink provided by the present invention includes an alcohol plasticizer, the mass of which is 0.2-3% of the mass of the thermoplastic biodegradable polymer material, and in a specific embodiment, it may be 0.2%, 0.5%, 1%, 1.5%, 2%, 2.5% or 3%. In the present invention, the alcohol plasticizer preferably includes one or more of polyethylene glycol, glycerol and polypropylene alcohol, and is more preferably polyethylene glycol. In the present invention, the number average molecular weight (Mn) of the polyethylene glycol is preferably 4000-8000 g / mol, and in a specific embodiment, it may be 4000 g / mol, 5000 g / mol, 6000 g / mol, 7000 g / mol or 8000 g / mol. In the present invention, the alcohol plasticizer can improve the mechanical properties of the insect pheromone attractant core formed by 3D printing, and increase its flexibility and ductility. This helps to maintain the morphology of the material during 3D printing, and may also improve the adaptability of the insect pheromone attractant core in actual use. When the alcohol plasticizer is polyethylene glycol (PEG), it also has the following effects: PEG has good solubility in solvents and can help dissolve other ingredients, especially for some poorly soluble compounds, it can provide a good dissolution environment, facilitating the preparation and uniform distribution of insect pheromone attractants; in addition, PEG can also regulate the release performance of the attractant, it affects the release rate of sex pheromones by changing the physical properties of the attractant, thereby improving the effect and duration of the attractant.

[0025] The insect pheromone ink provided by the present invention includes graded volatile organic solvents. The graded volatile organic solvents include at least one high-volatile organic solvent and at least one low-volatile organic solvent; the high-volatile organic solvent preferably includes at least one of acetone, dichloromethane and ethanol; the low-volatile organic solvent preferably includes at least one of N,N-dimethylformamide and dimethyl sulfoxide. In the present invention, the volume percentage of the high-volatile organic solvent in the graded volatile organic solvent is preferably 70-80%. The present invention selects graded volatile organic solvents. At room temperature, the high-volatile organic solvent helps the ink to dry quickly at room temperature, thereby maintaining the molding ability during the printing process, while the residual low-volatile organic solvent helps to maintain the fluidity of the ink and ensure the smoothness of the printing process.

[0026] The insect pheromone ink provided by the present invention includes insect pheromones, and the mass of the insect pheromone is 0.01-15% of the mass of the thermoplastic biodegradable polymer material, which can be adjusted by those skilled in the art according to actual needs. In an embodiment of the present invention, the mass of the insect pheromone can be 0.01%, 0.2%, 1%, 3%, 5%, 6%, 8%, 10%, 12%, 14% or 15% of the mass of the thermoplastic biodegradable polymer material, which will not be exhaustively listed here. The present invention does not specifically limit the specific type of the insect pheromone, which can be selected according to actual needs, such as the sex pheromone of the pear borer and the sex pheromone of the striped stem borer.

[0027] As a preferred solution, the insect pheromone ink provided by the present invention further comprises an aqueous solution of a functional material; the functional material preferably comprises lignin sulfonate and a metal salt; the lignin sulfonate preferably comprises sodium lignin sulfonate and / or calcium lignin sulfonate; the metal salt preferably comprises one or more of a trivalent iron salt, an aluminum salt and a divalent copper salt. In the present invention, the trivalent iron salt preferably comprises ferric chloride, more preferably anhydrous ferric chloride; the aluminum salt preferably comprises aluminum chloride, more preferably anhydrous aluminum chloride; the divalent copper salt preferably comprises copper chloride, more preferably anhydrous copper chloride.

[0028] In the present invention, the concentration of lignin sulfonate and metal salt in the aqueous solution of the functional material is preferably 0.25-1 g / mL independently, and in a specific embodiment, it can be 0.25 g / mL, 0.5 g / mL, 0.75 g / mL or 1 g / mL independently. In the present invention, the mass of the lignin sulfonate is preferably 0.02-0.5% of the mass of the thermoplastic biodegradable polymer material, and in a specific embodiment, it can be 0.02%, 0.1%, 0.2%, 0.3%, 0.4% or 0.5%; the mass of the metal salt is preferably 0.1-2.5% of the mass of the thermoplastic biodegradable polymer material, and in a specific embodiment, it can be 0.1%, 0.5%, 1%, 1.5%, 2% or 2.5%. The present invention introduces lignin sulfonate and metal ions to enhance the anti-ultraviolet ability and cross-linking effect of the insect pheromone attractant formed by 3D printing, and improve the stability and applicability of the attractant.

[0029] By controlling the dosage of each component, the insect pheromone ink obtained by the present invention has good rheological properties, which helps the ink to smoothly pass through the printing nozzle for 3D printing.

[0030] The present invention provides a method for preparing the insect pheromone ink described in the above scheme, comprising the following steps: dissolving an alcohol plasticizer in a graded volatile organic solvent, and sequentially adding insect pheromone and a thermoplastic biodegradable polymer material to the obtained solution to obtain the insect pheromone ink.

[0031] When the insect pheromone ink also includes an aqueous solution of functional materials, the method for preparing the insect pheromone preferably includes the following steps: dissolving an alcohol plasticizer in a graded volatile organic solvent, and sequentially adding an aqueous solution of functional materials, insect pheromones and a thermoplastic biodegradable polymer material to the obtained solution to obtain the insect pheromone ink.

[0032] In the present invention, after each raw material is added, the present invention preferably stirs evenly. The present invention has no special requirements on the speed and time of stirring, and stirring evenly is sufficient.

[0033] In the present invention, in order to remove bubbles, the insect pheromone ink is preferably sealed in a sealed container and left to stand for 12 hours.

[0034] The present invention provides an insect pheromone attractant core, which is prepared by 3D printing of the insect pheromone ink described in the above scheme.

[0035] The present invention provides a method for preparing the insect pheromone attractant core described in the above scheme, comprising the following steps: 3D printing the insect pheromone ink described in the above scheme, wherein the layer height of the 3D printing is 0.8-1.5 mm, the filling density is 70-100%, and the printing speed is 10-20 mm / s.

[0036] In a specific embodiment, the layer height of the 3D printing can be 0.8 mm, 1 mm, 1.2 mm or 1.5 mm, and more preferably the layer height of the first layer is 0.8 mm and the heights of the remaining layers are 1 mm.

[0037] In specific embodiments, the filling density of the 3D printing can be 70%, 75%, 80%, 85%, 90%, 95% or 100%.

[0038] In a specific embodiment, the printing speed of the 3D printing can be 10 mm / s, 15 mm / s or 20 mm / s.

[0039] In the present invention, the nozzle diameter of the 3D printing is preferably 0.8 mm or 1.2 mm.

[0040] The present invention does not impose any special limitation on the printing model used for the 3D printing, and can be set according to actual needs. For example, a cylindrical shape with a bottom radius of 5 to 20 mm and a height of 5 to 15 mm can be selected; or a cubic shape with a length and width of 10 to 30 mm and a height of 5 to 15 mm.

[0041] The present invention provides the use of the insect pheromone attractant core described in the above scheme in pest control.

[0042] The present invention provides a method for recycling and reusing the insect pheromone attractant core described in the above scheme, comprising the following steps: mixing the powder of the recycled insect pheromone attractant core and the insect pheromone with graded volatile organic solvents to obtain drug-loaded ink, which is used again for 3D printing.

[0043] In the present invention, the mixing preferably comprises: dissolving the insect pheromone in a graded volatile organic solvent, adding the powder of the recovered insect pheromone attractant core to the obtained solution, and stirring.

[0044] The insect pheromone ink, insect pheromone attractant core, preparation, application and recovery thereof provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0045] The following examples and comparative examples are used in the following raw materials: Cellulose acetate (CA, Mn=60000 g / mol, acetyl content=39.5 wt%); polyethylene glycol (PEG, Mn=4000 g / mol); acetone (purity greater than 99.8%); N,N-dimethylformamide (DMF); anhydrous ferric chloride (FeCl3) and sodium lignin sulfonate (SLS). In the present invention, analytical grade chemicals and reagent grade solvents were used without further purification. Pear fruit borer sex pheromone ((Z,E)-8-dodecene ethyl ester).

[0046] Example 1 At room temperature (25°C), polyethylene glycol (2% of the mass of CA) was dissolved in a mixed solvent of acetone and N,N-dimethylformamide (4:1, v / v); then, the sex pheromone of the pear borer (0.2% of the mass of CA) was added and stirred at 500 rpm on a magnetic stirrer for 30 minutes until the solution was uniform. Then, 15% cellulose acetate (mass proportion in the ink) was added and mechanically stirred at 800 rpm for 5 minutes to finally obtain a semi-solid insect pheromone ink. To remove bubbles, the obtained ink was sealed in a sealed container and left to stand for 12 h, then sealed and stored in a refrigerator at 4°C for later use, which was recorded as CP ink.

[0047] Example 2 The difference from Example 1 is that an aqueous solution of sodium lignin sulfonate and anhydrous ferric chloride is used for modification, and the specific steps are as follows: At room temperature (25°C), polyethylene glycol (2% by mass of CA) was dissolved in a mixed solvent of acetone and N,N-dimethylformamide (4:1, v / v); then, an aqueous solution of sodium lignin sulfonate and anhydrous ferric chloride was added (the concentrations of sodium lignin sulfonate and anhydrous ferric chloride were both 0.5 g / mL, the mass of sodium lignin sulfonate was 0.1% by mass of CA, and the mass of anhydrous ferric chloride was 0.5% by mass of CA), followed by the addition of the sex pheromone of the pear borer (0.2% by mass of CA), and stirred on a magnetic stirrer at 500 rpm for 30 minutes until the solution was uniform. Next, 15% cellulose acetate (mass percentage in the ink) was added, and mechanical stirring was performed at 800 rpm for 5 minutes to finally obtain a semi-solid insect pheromone ink. To remove bubbles, the obtained ink was sealed in a sealed container and allowed to stand for 12 h, then sealed and stored in a refrigerator at 4°C for later use, and recorded as CP-SL-Fe ink. The preparation flow chart of Example 2 is shown in the following figure. Figure 1 shown.

[0048] Application Examples In order to improve the efficiency of bait preparation, the present invention adopts a cubic model for printing, the size of which is 20 mm×20 mm×10 mm, and is modeled by SOLIDWORKS software, and sliced ​​by Repetier-Host software. The insect pheromone ink is printed by an extrusion 3D printer (Foodbot-D1, Shiyin Technology). The parameters are set as follows: the nozzle diameter is 0.8 mm, the printing layer height is 1 mm, and the layer height of the first layer is 0.8 mm; the filling density is set to 90%; and the printing speed is 15 mm / s. The printing parameters of the two inks in Example 1 and Example 2 are the same, and both are directly extruded and printed and formed at room temperature 25°C. The bait prepared in Example 1 is referred to as CP bait, and the bait prepared in Example 2 is referred to as CP-SL-Fe bait.

[0049] Figure 2 The photos of extrusion molding of CP and CP-SL-Fe inks show that both inks have good printability and excellent molding ability.

[0050] Comparative Example 1 Preparation of pheromone lure core with only lignin added but no iron added (named as CP-SL lure core): In order to compare the effect of metal ions in the modification process, the present invention only adds sodium lignin sulfonate but not anhydrous ferric chloride during the modification process. Other preparation and printing operations are consistent with Example 2 and the application example. The obtained lure is referred to as CP-SL lure.

[0051] Comparative Example 2 Preparation of unmodified empty vector (named CP-K empty vector): At room temperature (25°C), polyethylene glycol (2% of the mass of CA) was dissolved in a mixed solvent of acetone and N,N-dimethylformamide (4:1, v / v); then stirred at 500 rpm on a magnetic stirrer for 30 minutes until the solution was uniform. Then, 15% cellulose acetate (mass proportion in the ink) was added and mechanically stirred at 800 rpm for 5 minutes to finally obtain a semi-solid non-drug-loaded ink, which was sealed in a sealed container and allowed to stand for 12 hours before printing. The printing parameters were the same as those in the application example, and an unmodified empty carrier was obtained, referred to as CP-K empty carrier.

[0052] Structure and performance characterization (1) Characterization of ink rheological properties The rheological properties of the ink were analyzed using a rheometer (MCR502, Anton Paar, Austria). The rheological properties tests included shear viscosity test and oscillatory stress sweep test, both of which were performed using PP25 parallel plates (25 mm diameter, 1 mm gap) at a constant temperature of 25 °C. -1 The shear viscosity analysis was performed under the condition of constant frequency of 10 rad / s and strain range of 1% to 1000%, and the storage modulus (G′) and loss modulus (G″) of the ink were obtained. The test results are shown in Figure 3 , where (a) is the functional relationship between the viscosity of the two inks and the shear rate, and (b) is the relationship between the storage modulus (G′) and the loss modulus (G″) and the oscillation stress.

[0053] Depend on Figure 3 It can be seen that both CP and CP-SL-Fe exhibit shear thinning behavior when the shear rate continues to increase ( Figure 3 (a)), at 0.1 s -1 The viscosity under shear rate increases from 1.46 MPa∙s for CP ink to 1.62 MPa∙s for CP-SL-Fe ink. 3+ The introduction of CA, SLS and Fe 3+ The shear thinning behavior is crucial for DIW 3D printing because it enables the ink to be extruded through the nozzle at relatively low pressure. As the shear rate increases to 100 s -1 When the ink is heated to 400 ℃, the viscosity of both inks drops to about 700 Pa∙s, which helps the inks pass through the printing nozzle smoothly.

[0054] In addition, the modulus of the ink is also important in controlling the shape fidelity of the printed structure. Figure 3As shown in (b), both inks have a solid-like texture, which can be confirmed by the fact that the storage modulus (G′) is significantly higher than the loss modulus (G″) (more than 8 times). Obviously, the storage modulus (G′) and loss modulus (G″) of the modified CP-SL-Fe ink are higher than those of the CP ink, which further confirms the strengthening effect after modification. The intersection of the G′ and G″ curves shows that the yield stress (τy) of the CP ink is about 237 Pa, while the yield stress of the CP-SL-Fe ink is 194 Pa. This shows that the extrusion smoothness of the CP-SL-Fe ink is better than that of the CP ink. Nevertheless, both inks can be printed smoothly during printing.

[0055] (2) Characterization of 3D printed lure surface morphology 3D printed lure cores must not only meet green agricultural requirements such as slow release and biodegradability, but also have excellent morphological structures to ensure stability during transportation and application and be able to adapt to complex field environments. The present invention successfully printed lure core small pieces CP and CP-SL-Fe ( Figure 4 (a) and (c)), and the surface morphology of the printed lure was observed by three-dimensional ultra-depth microscopy ( Figure 4 The results show that the lines on the surface of the printed lure have a regular arrangement of ups and downs, and no obvious defects are found.

[0056] The surface morphology of the 3D printed CP lure and CP-SL-Fe lure was analyzed by scanning electron microscopy (SEM). Figure 5 .exist Figure 5 It can be clearly observed in (a) and (c) that cellulose ether forms a block-like bonding structure under the action of organic solvent and PEG, which can prove that the ink forms a tight cross-linking under the action of shear force during the printing process. Figure 5 Compared with (b), the surface of the CP-SL-Fe lure shows obvious wrinkles (see Figure 5 This phenomenon can be attributed to the coordination cross-linking effect between iron ions and polymers (CA, PEG and SLS).

[0057] In addition, the distribution of Fe in the CP-SL-Fe lure was observed by energy dispersive spectroscopy (EDS). Figure 6 . Figure 6 This indicates that the introduced Fe ions are evenly distributed on the CP-SL-Fe core, further verifying that the material has been successfully modified and has good uniformity and stability.

[0058] (3) 3D printing core chemistry and crystal structure characterization In order to detect the chemical structure of the pheromone lure core prepared by 3D printing, FTIR tests were performed on the CP lure core, CP-SL-Fe lure core and CP-SL lure core modified with only SLS (preparation method see Comparative Example 1). The results are shown in Figure 7 (a) In all 3D printed lures, the FTIR spectra at 1700 cm -1 The characteristic peak of the acetate group is at 2920cm -1 The peaks at 1498 cm -1 An absorption peak appeared at 3414 cm-1, indicating that aromatic ring vibration exists in both CP-SL and CP-SL-Fe. Compared with CP and CP-SL cores, the −OH peak in CP-SL-Fe core increased from 3414 cm-1 to 3414 cm-1. -1 Displacement to 3446 cm -1 , that is, after the addition of iron ions, the −OH peak shifts to the left. This may be due to the fact that Fe 3+ The coordination bond with -OH in the material is enhanced, weakening the hydrogen bonds between the molecular chains. The above phenomenon can preliminarily prove that the modified CP-SL-Fe core forms a more complex cross-linked structure at the chemical level through hydrogen bonds and coordination bonds.

[0059] XRD was used to further analyze the changes in the crystal structure of the CP core, CP-SL core and CP-SL-Fe core before and after the coordination crosslinking reaction. Figure 7 (b). The characteristic diffraction peaks of cellulose I crystal structure can be observed at scattering angles of 2θ = 14.1° and 24.5° for CP and CP-SL cores, while the characteristic peak at scattering angle 2θ = 14.1° for CP-SL-Fe core disappears. It may be that the introduction of metal ions affects the intermolecular interaction between the composite materials, thereby reducing the crystallinity. The decrease in the crystallinity of the material and the increase in the internal amorphous area or disordered structure may help the loading and sustained release of drugs.

[0060] In addition, X-ray photoelectron spectroscopy (XPS) was used to track the chemical structure evolution of the 3D printed lure before and after modification. Compared with the CP lure, the XPS data of the CP-SL-Fe lure ( Figure 7 Figures (c), (d), and (e) show that the content of C–O groups increased significantly, while the content of C=O groups decreased slightly. This may be due to the addition of more hydroxyl and ether groups to the material after the introduction of sodium lignin sulfonate, or it may be that Fe³⁺ coordinates with oxygen-containing functional groups (such as hydroxyl and ether groups) in the SLS molecules, thereby enhancing the cross-linking effect. This SLS-Fe³⁺ coordination effect can not only improve the stability of the material, but also change the distribution and properties of surface functional groups.

[0061] (4) Research on the physical properties of 3D printed lure core Thermogravimetric analysis experiments were conducted on a HITACHI STA200 thermogravimetric analyzer (TGA). The experiment was conducted in a nitrogen atmosphere, with the temperature range increasing from 30°C to 600°C at a heating rate of 10°C / min. By comparing the thermogravimetric curves of the unmodified empty carrier (CP-K, preparation method see Comparative Example 2), the unmodified pheromone attractant core (CP) and the modified pheromone attractant core (CP-SL-Fe), the thermal stability of different samples during the heating process and their differences were analyzed. Results are shown in Figure 8 Middle (a).

[0062] TGA analysis results ( Figure 8 (a) shows that when the temperature reaches 120°C, the empty carrier (CP-K) shows a 27% weight loss, while the drug-loaded attractants (CP, CP-SL-Fe) lose about 30% of their weight, which may be related to the thermal decomposition and volatilization of pheromones. Compared with CP-K and CP, the decomposition temperature of the CP-SL-Fe attractant increased from 215°C to 229°C, indicating that the cross-linking degree of the modified material increased, thereby improving the thermal stability of the attractant to a certain extent. In addition, the decomposition rate of the CP-SL-Fe attractant accelerated at 300°C, which may be caused by the decomposition of sodium lignin sulfonate.

[0063] The prepared 3D printed lure core was placed on an electronic universal testing machine for a standard compression test, with the loading rate set to 0.5 mm / min. The stress-strain curve was plotted and the results are shown in Figure 8 (b). The maximum compressive strength σ of the 3D printed lure is further calculated based on the compression strength formula and the elastic modulus formula. max and elastic modulus .

[0064] The compression test data showed that the compression strength of CP was 51.06MPa and the compression modulus was 1.47GPa; the compression strength of CP-SL-Fe was 87.96MPa and the compression modulus was 1.87GPa, indicating that the lure core can meet the transportation and field application requirements under certain strength and pressure. In addition, the compressive strength of CP-SL-Fe lure core is better than that of CP, indicating that it has stronger compression resistance and deformation resistance, and shows higher stability. By comparing the stress-strain curves before and after modification ( Figure 8 In (b), it can be found that the curves of the two are similar, indicating that although the compression strength and compression modulus have increased, the deformation modes of the two are basically the same.

[0065] The surface of the 3D printed sample was tested for diffuse reflection using a Shimadzu UV-3600 UV / visible / near infrared spectrometer with a test wavelength range of 200 nm to 800 nm. Through the test, the reflectivity (R%) curve of the 3D printed sample before and after modification was obtained. The results are shown in Figure 8 Middle (c).

[0066] UV-Vis diffuse reflectance ( Figure 8 (c) shows that the reflectivity of CP core to ultraviolet and visible light is higher than that of CP-SL-Fe core. Sodium lignin sulfonate itself has light absorption properties, and its introduction may enhance the light absorption capacity of the material, especially in the ultraviolet region. Therefore, the addition of sodium lignin sulfonate may replace the reflection effect by improving the material's ability to absorb ultraviolet light. In general, whether by reflecting or absorbing ultraviolet light, the surface of the material can play a role in protecting the internal drugs to a certain extent. It is worth noting that the water contact angle of the surface of the modified material is significantly improved ( Figure 8 In (d), the angle of attraction increases from 29.4° for the original material CP core to 56.6° for the CP-SL-Fe core. This change indicates that the modification of the surface microstructure of the material plays an important role in improving the hydrophobic performance.

[0067] (5) Characterization of degradation performance of 3D printed lure core In order to evaluate the biodegradability of the 3D printed baits, the 3D printed baits (CP and CP-SL-Fe) before and after modification and the commercial rubber plug baits (CK) (both the commercial rubber plugs and the 3D printed baits were loaded with 1 mg of the sex pheromone of the pear borer, and the rubber plug loading method was: the pheromone was dissolved in n-hexane to prepare a 1g / 200mL mother solution, and 200 μL was dropped on the rubber plug. The rubber allowed the pheromone to penetrate into the material through solvent penetration, and then combined with the pheromone by physical adsorption) were buried in natural soil at a depth of 10 cm. The weight of the sample was recorded every 30 days, the weight loss ratio was calculated, and the temperature and humidity of the soil were recorded. Three parallel samples were set up for each group of experiments.

[0068] like Figure 8 As shown in (f), the biodegradability of the 3D printed bait core was tested in a natural soil environment. Figure 8 (e) shows that as the test time increases, the weight loss rate of the 3D printed lure gradually increases, while the mass of the commercial rubber stopper hardly changes. The weight loss rates of CP and CP-SL-Fe at 105 days were 17.65% and 20.35%, respectively. The main microorganisms that degrade the 3D printed lure are fungi, bacteria, and actinomycetes, which are special decomposers of cellulose and lignin structures. The results show that the 3D printed lure has certain biodegradability compared to the commercially available rubber stopper.

[0069] (6) Characterization of 3D printed lure encapsulation effect and release performance Drug encapsulation and release performance is also one of the core of sex attractant development. The encapsulation rates of CP and CP-SL-Fe were tested to be 95.39% and 96.21% respectively, indicating that the drug was well encapsulated in the material.

[0070] The 3D printed drug-loaded blocks before and after modification were placed in a fume hood at a room temperature of 25±2°C (good ventilation, no directional airflow), and samples were taken at different time points. The residual pheromone content was analyzed by gas chromatography (GC), with three replicates per group. Fig. 9 (a). The results showed that in the second week, the pheromone release of the bait core before and after modification was 41.9% (CP bait core) and 57.17% (CP-SL-Fe bait core), respectively. Both experienced an initial burst release, followed by a slow release, and the release time could reach more than six weeks. It is speculated that the 3D printed bait core may also have two stages: rapid release on the surface and slow release on the inner layer. In the later slow release process, the surface material played a better protective role for the inner layer drug. In addition, the release rate of the CP-SL-Fe bait core began to slow down after two weeks and was slower than that of the CP bait core. Its cumulative release rate on the 47th day was 84.43%, while that of the CP bait core was 90.57%. The results show that the sustained release mechanism of pheromones may rely on the enhancement of intermolecular interactions (such as coordination bonds and hydrogen bonds) between polymers in the 3D printed bait core, thereby forming a denser structure, so that the pheromone is tightly wrapped in the cross-linked structure, thereby slowing down the release rate.

[0071] In order to further study the release behavior of pheromones in 3D printed bait cores, commonly used drug release kinetic models, including zero-order model, first-order model, Higuchi model and Ritger-Peppas model, were used for simulation. Fig.10 , comparing the four models, the coefficient of determination R of the two 3D printed lures after fitting the first-order release model 2 The value is the highest, so the release behavior of pheromone is closer to the first-order release kinetic model. Preliminary research on indoor release experiments shows that insect pheromone attractants prepared by 3D printing technology are expected to achieve long-term pest control effects in the field.

[0072] (7) Field trapping ability test In the research of relevant information hormonal lures, field trapping experimental data are relatively limited. Although the field environment is more complex and changeable, it is still an important means to test the application performance and biological activity of lures. This part of the results of the present invention will promote the further development of 3D printing technology in this field. Fig. 9 (b) shows the actual application of the 3D printed lure combination trap in the field. Fig. 9(c) shows that the 3D printed lure exhibits excellent trapping effect. Among them, the overall performance of the CP-SL-Fe lure is better than that of the CP lure, and its duration is comparable to that of the commercially available lure. It is worth noting that the CP-SL-Fe lure has a better trapping effect than the commercially available rubber plug lure in the first three weeks, which is consistent with its early rapid release characteristics. At the same time, the cumulative trapping amount ( Fig. 9 Figure (d) also shows that the CP-SL-Fe lure trapped more pear borer in six weeks. The above trapping results fully demonstrate the effectiveness of the 3D printed lure, and its persistence in complex field environments has also been verified. In addition, the present invention further proves that CP-SL-Fe can better encapsulate drugs under complex cross-linking such as hydrogen bonds and coordination bonds, thereby performing well in indoor release and field trapping, providing a strong basis for the subsequent in-depth study of slow-release lures.

[0073] (8) Research on the recyclability of 3D printed lure cores The 3D printed lure cores were recycled and reused after field use. First, the recycled 3D printed lure core (CP-SL-Fe) was crushed into powder by physical grinding. Then, a certain amount of pheromone (the sex pheromone of the pear borer accounted for 0.2% of the mass of the recycled powder) was fully dissolved in a mixed organic solvent, specifically a mixed solvent of acetone and DMF (4:1, v / v). Then a certain amount of the recycled powder was added to the mixed solvent, accounting for 15% of the mass of the insect pheromone ink. Mechanical stirring was performed at 800 rpm for 5 minutes to prepare the recycled insect pheromone ink, and it was printed again. The printing steps and parameters were consistent with the previous application example. The lure core was named rCP-SL-Fe lure core. To verify the effectiveness of this recycling and reuse strategy, the surface morphology, drug encapsulation efficiency, Fourier transform infrared spectroscopy (FTIR), mechanical properties and wettability of the secondary printed lure core were systematically evaluated. The printing process and parameters were consistent with the previous article.

[0074] The results showed that after simple treatment, the material could be recycled and reused for 3D printing to make pheromone-loaded attractant cores (rCP-SL-Fe). Fig.11 Figures (a) and (b) show the process of recycling materials from the field to printing ink, which only requires physical grinding and solvent dissolution. Fig.11 The recycled ink shown in (c) and (d) has good extrusion effect and plasticity. SEM-ESD results ( Fig.11 (e), (f) show that the surface of the re-printed lure core presents a tightly cross-linked, regularly arranged structure, with evenly distributed iron elements, showing surface morphology characteristics similar to those of the first-printed lure core. The characteristic peaks in FTIR analysis are consistent with the results of the previous study ( Fig.11(g). The encapsulation efficiency of the lure core was 92.8%, indicating that the encapsulation efficiency of insect pheromones remained at a high level ( Fig.11 (h)). It is worth noting that the compression strength and compression modulus of the recycled and reprinted pheromone lure are 124.28MPa and 2.03GPa respectively, and the surface water contact angle is 84.51°. From the stress-strain curve ( Fig.11 In (i)), water contact angle data, some properties of rCP-SL-Fe lure are better than CP-SL-Fe lure. This may be due to the enhanced cross-linking structure between materials during the secondary dissolution process, making it more compact. The above experimental results prove the feasibility of recycling and reusing 3D printed lure. This treatment method is simple in process and combines the advantages of 3D printing efficient molding, providing a direction for efficient and rapid reuse of lure.

[0075] From the above results, it can be seen that the present invention successfully prepared two insect pheromone inks with excellent printing performance. The 3D printed pheromone attractant cores showed good surface morphology, excellent physical and chemical properties, and good encapsulation and release characteristics. After modification, the overall performance of the attractant core was improved. In addition, the 3D printed insect pheromone attractant cores showed good results in preparation process, field application and green sustainability, showing great development potential. With the continuous development of agricultural technology and the advancement of interdisciplinary research, the application prospects of 3D printing technology in the agricultural field will be broader.

[0076] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. An insect pheromone ink, characterized in that: The invention comprises the following components: thermoplastic biodegradable polymer material, alcohol plasticizer, graded volatile organic solvent and insect pheromone; The fractionated volatile organic solvents include at least one high volatility organic solvent and at least one low volatility organic solvent; The mass content of the thermoplastic biodegradable polymer material in the insect pheromone ink is 12-16%; The mass of the alcohol plasticizer is 0.2-3% of the mass of the thermoplastic biodegradable polymer material; The mass of the insect pheromone is 0.01-15% of the mass of the thermoplastic biodegradable polymer material.

2. The insect pheromone ink according to claim 1, characterized in that: Also included is an aqueous solution of a functional material; the functional material includes lignin sulfonate and a metal salt; the concentration of the lignin sulfonate and the metal salt in the aqueous solution of the functional material is independently 0.25 to 1 g / mL; The mass of the lignin sulfonate is 0.02-0.5% of the mass of the thermoplastic biodegradable polymer material; the mass of the metal salt is 0.1-2.5% of the mass of the thermoplastic biodegradable polymer material; the metal salt includes one or more of trivalent iron salt, aluminum salt and divalent copper salt.

3. The insect pheromone ink according to claim 2, characterized in that: The lignin sulfonate includes sodium lignin sulfonate and / or calcium lignin sulfonate; The ferric iron salt includes ferric chloride; the aluminum salt includes aluminum chloride; and the divalent copper salt includes copper chloride.

4. The insect pheromone ink according to claim 1 or 2, characterized in that: The thermoplastic biodegradable polymer material includes one or more of polylactic acid, polycaprolactone, polyhydroxybutyrate and cellulose acetate.

5. The insect pheromone ink according to claim 1 or 2, characterized in that: The alcohol plasticizer includes one or more of polyethylene glycol, glycerol and polypropylene alcohol.

6. The insect pheromone ink according to claim 1 or 2, characterized in that: The high volatility organic solvent includes at least one of acetone, dichloromethane and ethanol; the low volatility organic solvent includes at least one of N,N-dimethylformamide and dimethyl sulfoxide.

7. An insect pheromone attractant, characterized in that: The insect pheromone ink according to any one of claims 1 to 6 is prepared by 3D printing.

8. The method for preparing the insect pheromone lure core according to claim 7, characterized in that: The method comprises the following steps: 3D printing the insect pheromone ink according to any one of claims 1 to 6, wherein the layer height of the 3D printing is 0.8 to 1.5 mm, the filling density is 70 to 100%, and the printing speed is 10 to 20 mm / s.

9. Use of the insect pheromone attractant according to claim 7 in pest control.

10. The method for recycling the insect pheromone lure core according to claim 7, characterized in that: The following steps are involved: The powder of the recycled insect pheromone attractant core and the insect pheromone are mixed with graded volatile organic solvents to obtain drug-loaded ink, which is used again for 3D printing.

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