Environment-friendly termite trapping and killing strip and preparation method thereof

Abstract

The invention relates to the technical field of termite trapping and killing, and particularly discloses an environment-friendly termite trapping and killing strip and a preparation method thereof. The environment-friendly termite trapping and killing strip is prepared from microcrystalline cellulose, sodium carboxymethyl cellulose, potassium sorbate, pine sawdust, tapioca flour, xanthan gum and killing microcapsules. The killing microcapsule comprises a capsule wall and a capsule core, wherein the capsule core is prepared from the following raw materials: triflumuron, diflubenzuron, ammonium chloride, petroleum ether and sodium dodecyl benzene sulfonate; the capsule wall is prepared from the following raw materials: modified chitosan, sodium alginate, modified corn straw powder, Arabic gum and a sugarcane extract. According to the environment-friendly termite trapping and killing strip, all the components are matched, the excellent insecticidal effect is achieved, the pesticide can be slowly released through the killing microcapsules, the insecticidal time is prolonged, and the prepared trapping and killing strip can kill insects for a long time.

Description

Technical Field

[0001] The present application relates to the technical field of termite trapping, and more specifically, to an environmentally friendly termite trapping strip and a preparation method thereof. Background Art

[0002] Termites are social insects that pose a certain threat to people's food, clothing, housing and transportation. For example, they destroy buildings, erode crops and trees, and damage infrastructure such as wires and pipes. The harm caused by termites is hidden, widespread and serious.

[0003] In the prior art, methods for preventing and controlling termites include chemical control, physical control and biological control. Among them, chemical control is widely used due to its rapid effect in killing termites and simple operation. For example, cypermethrin, permethrin, cypermethrin, imidacloprid and bifenthrin are used to kill termites to prevent termite invasion.

[0004] Usually, a mixture of attractants and pesticides is used to make bait strips, which are placed in termite activity areas. Termites naturally find and eat the bait, and the pesticides are used to kill the termites. However, it may take several weeks or even longer for the termites to find the bait strips. The volatilization of the pesticide during this period will reduce the insecticidal effect, thereby affecting the efficiency of killing termites. Summary of the Invention

[0005] In order to improve the problem that using termite trapping strips takes a long time to kill termites, causing the insecticide to volatilize too quickly and reducing the insecticidal effect, the present application provides an environmentally friendly termite trapping strip and a preparation method thereof.

[0006] In a first aspect, the present application provides an environmentally friendly termite trapping strip, which adopts the following technical solution: An environmentally friendly termite trapping strip comprising the following raw materials: microcrystalline cellulose, sodium carboxymethyl cellulose, potassium sorbate, pine sawdust, cassava flour, xanthan gum, and termite killing microcapsules; The killing microcapsule comprises a capsule wall and a capsule core, wherein the capsule core comprises the following raw materials: triflumuron, diflubenzuron, ammonium chloride, petroleum ether, and sodium dodecylbenzenesulfonate; The capsule wall comprises the following raw materials: modified chitosan, sodium alginate, modified corn straw powder, gum arabic and sugarcane extract.

[0007] By adopting the above technical solution, hydrogen bonds exist between the microcrystalline cellulose molecules in the trapping strip. When compressed, the hydrogen bonds are combined, and the strip has high compressibility and adhesion, so that the various components in the trapping strip are tightly bonded. It also has a lubricating effect, which reduces the friction between the particles of the various components and improves the fluidity of the particles of the various components, thereby facilitating the molding of the trapping strip. Sodium carboxymethyl cellulose has thickening, bonding and film-forming effects, which can enable the trapping strip to be better molded. Potassium sorbate serves as a preservative, which effectively maintains the biological activity of the various components and extends the storage period of the trapping strip. Pine sawdust and cassava flour serve as termite attractants, which can attract termites, and then the killing agent in the killing microcapsule kills the termites. Xanthan gum has appropriate viscosity, which can control the shape and structure of the trapping strip to maintain and enhance the texture of the trapping strip, thereby better controlling the taste of the trapping strip and preventing it from breaking.

[0008] In the capsule core of the killing microcapsule, cyfluthrin, diflubenzuron and ammonium chloride have contact and stomach poison effects on termites and can kill termites. Petroleum ether is used as a solvent to better dissolve cyfluthrin, diflubenzuron and ammonium chloride evenly. Sodium dodecylbenzenesulfonate has excellent emulsification and dispersion effects, so that the various components in the capsule core are evenly mixed. In the capsule wall, the modified chitosan has good mechanical effect, film-forming property and biocompatibility, and has a good sustained-release effect. Sodium alginate and the modified chitosan undergo a cross-linking reaction, which further improves the film-forming property and mechanical properties of the system. The modified corn straw powder has more fibers and can be loaded in the cross-linked structure formed by the modified chitosan and sodium alginate, thereby improving the mechanical properties of the system and making the prepared capsule wall have a good embedding rate. Gum arabic has gelling, adhesion and thickening properties, which make the various components in the capsule wall adhere tightly, making the capsule wall better in film formation, embedding and not easy to rupture; the sugarcane extract has good antioxidant properties, better maintains the biological activity of the various components in the capsule wall, and makes the various components evenly mixed and better in film formation; the prepared killing microcapsules have good insecticidal effect, can slowly release drugs, prolong the insecticidal time, and the prepared trapping strips can kill insects for a long time.

[0009] Optionally, based on weight, 0.5-1.5 parts of microcrystalline cellulose, 2-3 parts of sodium carboxymethyl cellulose, 0.5-1 part of potassium sorbate, 2-4 parts of pine sawdust, 2-5 parts of cassava flour, 1-2 parts of xanthan gum, and 4-8 parts of miasma microcapsules; The capsule core contains 3-4 parts of triflumuron, 4-6 parts of diflubenzuron, 2-3 parts of ammonium chloride, 20-25 parts of petroleum ether, and 5-8 parts of sodium dodecylbenzenesulfonate; The capsule wall contains: 17-20 parts of modified chitosan, 10-13 parts of sodium alginate, 12-15 parts of modified corn straw powder, 2-5 parts of gum arabic, and 3-6 parts of sugarcane extract.

[0010] By adopting the above technical solution, the amount of each component is further limited, so that the combination of each raw material has a good insecticidal effect, the prepared trapping strip is easy to shape, pine sawdust and cassava flour attract termites, and the killing microcapsules can slowly release drugs and have a good insecticidal effect, so that the insecticidal time is extended, and the prepared trapping strip can kill insects for a long time.

[0011] Optionally, the preparation method of the modified chitosan comprises the following steps: (1) Dispersing chitosan in acetic acid solution, adding epichlorohydrin, and stirring at 50-55° C. for 2-3 hours to obtain a reaction solution; (2) dispersing carbon nanotubes in deionized water, adding modified silver nanofibers and N,N-dimethylformamide, and stirring at a temperature of 60-65° C. for 1-2 hours to obtain a mixed solution; (3) The reaction solution of step (1) and the mixed solution of step (2) are mixed, NaOH solution is added, the pH is adjusted to 10-11, stirred for 1-2 hours, cooled to 20-30° C., filtered, washed, and vacuum dried to obtain modified chitosan.

[0012] By adopting the above technical solution, chitosan is cross-linked with epichlorohydrin to form a gel network structure, thereby improving the mechanical properties and toughness of chitosan. In addition, other active groups are introduced into chitosan to help chitosan react with other components.

[0013] Carbon nanotubes have good mechanical properties and repair properties and can fill cracks. Modified silver nanofibers can be loaded on the surface and pores of carbon nanotubes to improve the antibacterial and repair properties of carbon nanotubes. N,N-dimethylformamide has a dispersing effect, making it difficult for carbon nanotubes and modified silver nanofibers to agglomerate, so that the modified silver nanofibers are evenly loaded on the carbon nanotubes. The carbon nanotubes loaded with modified silver nanofibers are mixed with chitosan, which not only improves the mechanical properties and antibacterial properties of chitosan, but also effectively repairs the cracks in chitosan, reduces the subsequent sustained-release efficiency of the capsule wall, prolongs the efficacy time of the killing microcapsules, and helps to trap and kill insects for a long time.

[0014] Optionally, the mass ratio of the chitosan, carbon nanotubes and modified silver nanofibers is 1:0.6-0.9:0.2-0.4.

[0015] By adopting the above technical solution, the mass ratio of chitosan, carbon nanotubes and modified silver nanofibers is further limited within a certain range, thereby improving the mechanical properties, antibacterial properties, film-forming properties and repair properties of chitosan. The carbon nanotubes have good mechanical properties and repair properties, and the modified silver nanofibers have good antibacterial properties and can be loaded on the surface of the carbon nanotubes, thereby improving the filling capacity of the carbon nanotubes, so that the carbon nanotubes loaded with modified silver nanofibers can be loaded in the network pores of chitosan, thereby improving the mechanical properties of chitosan. Subsequently, the microcapsule wall is made, so that the capsule wall has good mechanical properties and repair properties and is not easy to rupture.

[0016] Optionally, the preparation method of the modified silver nanofibers comprises the following steps: dispersing the silver nanofibers in deionized water, adding lauric acid, PVP and a silane coupling agent, and ultrasonicating at a temperature of 60-65° C. for 1-2 hours to obtain the modified silver nanofibers.

[0017] By adopting the above technical solution, silver nanofibers are easy to agglomerate, lauric acid has good surface activity, and can coat silver nanofibers, so that the silver nanofibers have good dispersibility and stability, PVP has good biocompatibility, chemical stability and strong bonding ability, can adjust the viscosity of the system, can further coat silver nanofibers, and subsequently have good film-forming properties, which is conducive to the film-forming properties of the capsule wall; the silane coupling agent and PVP are cross-linked and modified to improve the gel type of the system solution, and then coat the silver nanofibers, which subsequently makes the silver nanofibers have good mechanical properties, which is conducive to the subsequent improvement of the mechanical properties and film-forming properties of the capsule wall.

[0018] Optionally, the mass ratio of the silver nanofibers, PVP and silane coupling agent is 1:0.02-0.05:0.1-0.3.

[0019] By adopting the above technical solution, the mass ratio of silver nanofibers, PVP and silane coupling agent is further limited within a certain range, thereby improving the mechanical properties and film-forming properties of silver nanofibers. PVP has good film-forming properties and can coat silver nanofibers. The silane coupling agent and PVP are cross-linked and modified to improve the gel type of the system solution, thereby coating the silver nanofibers. There is a synergistic effect between the silver nanofibers, PVP and silane coupling agent, which makes the silver nanofibers have good mechanical properties, which is conducive to subsequently obtaining a capsule wall with good mechanical properties and film-forming properties.

[0020] Optionally, the method for preparing the modified corn straw powder comprises the following steps: (1) Crush the straw, sieve it, and then disperse it in a sodium hydroxide solution, stir it at 80-85°C for 2-3 hours, filter it, wash it with water, and then disperse it in deionized water, add fish meal, and stir it evenly to obtain a mixed solution; (2) Dispersing the modified diatomaceous earth in deionized water, adding the mixed solution of step (1), black fungus extract, sodium lauryl sulfate and hydroxymethyl cellulose, stirring evenly at 70-75° C., filtering, drying and grinding to obtain modified corn straw powder.

[0021] By adopting the above technical solution, sodium hydroxide erodes the surface of the straw particles to a certain extent, making the surface of the straw particles have more pores, thereby increasing the specific surface area of ​​the straw particles. Fish meal can be loaded on the surface of the straw particles, thereby increasing the nutritional value of the straw particles and helping to attract termites later.

[0022] The modified diatomaceous earth has good adsorption and filling properties, and the straw particles can be loaded on the surface and pores of the modified diatomaceous earth. The black fungus extract has good antioxidant properties, can maintain the biological activity of each component, and assists the straw particles in attracting termites. Sodium lauryl sulfate has emulsifying and dispersing properties, so that the various components are evenly dispersed. The hydroxymethyl cellulose has a certain viscosity, so that the modified diatomaceous earth and the straw particles are tightly bonded. The obtained modified corn straw powder has good filling properties, nutritional value and adsorption properties, and is subsequently applied to the capsule wall to effectively fill the gaps in the capsule wall and improve the mechanical properties of the capsule wall.

[0023] Optionally, the mass ratio of the straw, modified diatomaceous earth and hydroxymethyl cellulose is 1:0.2-0.5:0.07-0.09.

[0024] By adopting the above technical solution, the mass ratio of straw, modified diatomaceous earth and hydroxymethyl cellulose is further limited within a certain range, thereby improving the mechanical properties, adsorption and nutritional value of the straw particles. The modified diatomaceous earth has good adsorption and filling properties. The straw particles are loaded in the pores of the modified diatomaceous earth. The hydroxymethyl cellulose has a certain viscosity, which makes the straw particles and the modified diatomaceous earth adhere tightly, thereby improving the performance stability of the modified straw powder. The subsequent filling in the capsule wall improves the mechanical properties of the capsule wall, which helps to kill the bactericidal durability of the microcapsules.

[0025] Preferably, the preparation method of the modified diatomaceous earth comprises the following steps: grinding the diatomaceous earth, sieving it, and then calcining it at a temperature of 300-320°C for 2-3 hours, then dispersing it in a tartaric acid solution, stirring it for 1-2 hours, filtering it, and then dispersing it in deionized water, adding phenolic resin, aloe extract and hexaflumuron, stirring it evenly, and drying it to obtain the modified diatomaceous earth.

[0026] By adopting the above technical solution, diatomaceous earth is calcined to increase the specific surface area of ​​the diatomaceous earth, and organic impurities in the diatomaceous earth are removed, so that the diatomaceous earth has better adsorption capacity. Tartaric acid is used for further impurity removal to obtain acidified diatomaceous earth, thereby improving the biological activity of the diatomaceous earth. The diatomaceous earth is modified with phenolic resin to improve the adhesion of the diatomaceous earth, which subsequently helps the diatomaceous earth to adhere to straw particles. The aloe vera extract has good antioxidant properties and improves the biological activity of each component. Hexaflumuron can kill termites. Hexaflumuron is loaded in the modified diatomaceous earth, so that the capsule wall of the subsequent killing microcapsule also has insecticidal properties, thereby improving the insecticidal efficiency of the killing microcapsule.

[0027] In a second aspect, the present application provides a method for preparing an environmentally friendly termite trap strip, comprising the following steps: The preparation method of the microcapsule of the invention comprises the following steps: uniformly mixing triflumuron, diflubenzuron, ammonium chloride, petroleum ether and sodium dodecylbenzenesulfonate to obtain a capsule core; Modified chitosan, sodium alginate, modified corn straw, gum arabic, sugarcane extract and water are mixed to obtain capsule wall; capsule core, capsule wall and emulsifier are mixed, high pressure homogenized and spray dried to obtain killing microcapsules; Mix microcrystalline cellulose, sodium carboxymethyl cellulose, potassium sorbate, pine sawdust, cassava flour, xanthan gum, miasma microcapsules and water and stir for 25-30 minutes, press into shape, and dry to obtain the trapping strips.

[0028] By adopting the above technical solution, the present application mixes the various raw material components and performs compression molding, with a simple production process and high preparation efficiency, thereby obtaining an environmentally friendly termite trapping strip with excellent performance in all aspects and improving the insecticidal durability of the trapping strip.

[0029] In summary, this application has the following beneficial effects: 1. In the trapping strips of the present application, hydrogen bonds exist between the microcrystalline cellulose molecules. When compressed, the hydrogen bonds are associated, which has a high degree of compressibility and adhesion, so that the various components in the trapping strips are tightly bonded. It also has a lubricating effect, reducing the friction between the particles of each component, improving the fluidity of the particles of each component, and facilitating the molding of the trapping strips; pine sawdust and cassava flour are used as termite attractants to attract termites, and then the killing agent in the killing microcapsules kills the termites.

[0030] 2. In the present application, triflumuron, diflubenzuron and ammonium chloride have contact and stomach poisoning effects on termites and can kill termites. Petroleum ether is used as a solvent to better dissolve triflumuron, diflubenzuron and ammonium chloride evenly. Sodium dodecylbenzenesulfonate has an excellent emulsifying and dispersing effect, so that the various components in the capsule core are evenly mixed.

[0031] 3. The killing microcapsules prepared in this application have good insecticidal effects and can slowly release drugs, thereby prolonging the insecticidal time. The prepared trapping strips can kill insects for a long time. DETAILED DESCRIPTION

[0032] Preparation example of modified chitosan Preparation Example 1-1 The preparation method of modified chitosan comprises the following steps: (1) Disperse 1.2 kg of chitosan in 2 L of 12% acetic acid solution, add 0.2 kg of epichlorohydrin, and stir at 55°C for 3 h to obtain a reaction solution; (2) dispersing carbon nanotubes in 2.5 L of deionized water, adding modified silver nanofibers and 0.3 kg of N,N-dimethylformamide, and stirring at 65 °C for 2 h to obtain a mixed solution; (3) The reaction solution of step (1) and the mixed solution of step (2) were mixed, 1 L of 5% NaOH solution was added, the pH was adjusted to 11, stirred for 2 h, cooled to 30° C., filtered, washed, and vacuum dried to obtain modified chitosan.

[0033] The mass ratio of chitosan, carbon nanotubes and modified silver nanofibers is 1:0.6:0.2.

[0034] The preparation method of modified silver nanofibers comprises the following steps: dispersing 1 kg of silver nanofibers in 2 L of deionized water, adding 0.2 kg of lauric acid, PVP and a silane coupling agent, and ultrasonicating at a temperature of 65° C. for 2 hours to obtain modified silver nanofibers.

[0035] The mass ratio of silver nanofibers, PVP and silane coupling agent is 1:0.05:0.1.

[0036] Preparation Example 1-2 The difference from Preparation Example 1-1 is that in step (2), no carbon nanotubes are added.

[0037] Preparation Examples 1-3 The difference from Preparation Example 1-1 is that in step (2), modified silver nanofibers are not added.

[0038] Preparation Examples 1-4 The difference from Preparation Example 1-1 is that the mass ratio of chitosan, carbon nanotubes and modified silver nanofibers is 1:0.9:0.4.

[0039] Preparation Examples 1-5 The difference from Preparation Example 1-1 is that the mass ratio of chitosan, carbon nanotubes and modified silver nanofibers is 1:0.1:0.7.

[0040] Preparation Examples 1-6 The difference from Preparation Example 1-1 is that PVP is not added in the preparation method of the modified silver nanofibers.

[0041] Preparation Examples 1-7 The difference from Preparation Example 1-1 is that no silane coupling agent is added in the preparation method of the modified silver nanofiber.

[0042] Preparation Examples 1-8 The difference from Preparation Example 1-1 is that the mass ratio of silver nanofibers, PVP and silane coupling agent is 1:0.02:0.3.

[0043] Preparation Examples 1-9 The difference from Preparation Example 1-1 is that the mass ratio of silver nanofibers, PVP and silane coupling agent is 1:0.2:0.03.

[0044] Preparation example of modified corn straw powder Preparation Example 2-1 The preparation method of modified corn straw powder comprises the following steps: (1) 2.5 kg of straw was crushed, passed through a 60-mesh sieve, and then dispersed in 3 L of 2% sodium hydroxide solution. The mixture was stirred at 85°C for 3 h, filtered, washed with water, and then dispersed in 2.2 L of deionized water. 0.3 kg of fish meal was added and stirred to obtain a mixed solution. (2) Dispersing the modified diatomaceous earth in 2 L of deionized water, adding the mixed solution of step (1), 0.4 kg of black fungus extract, 0.3 kg of sodium lauryl sulfate and hydroxymethyl cellulose, stirring evenly at 75 ° C, filtering, drying, and grinding to obtain modified corn straw powder.

[0045] The mass ratio of straw, modified diatomaceous earth and hydroxymethyl cellulose is 1:0.2:0.09.

[0046] The preparation method of modified diatomaceous earth comprises the following steps: grinding 3 kg of diatomaceous earth, passing it through a 20-mesh sieve, calcining it at a temperature of 320° C. for 3 hours, dispersing it in 4 L of a 7% by mass tartaric acid solution, stirring it for 2 hours, filtering it, and then dispersing it in 2.5 L of deionized water. 0.4 kg of phenolic resin, 0.2 kg of aloe extract, and 0.7 kg of hexaflumuron are added, stirring it evenly, and drying it to obtain the modified diatomaceous earth.

[0047] Preparation Example 2-2 The difference from Preparation Example 2-1 is that in step (2), modified diatomaceous earth is not added.

[0048] Preparation Example 2-3 The difference from Preparation Example 2-1 is that in step (2), hydroxymethyl cellulose is not added.

[0049] Preparation Example 2-4 The difference from Preparation Example 2-1 is that the mass ratio of straw, modified diatomaceous earth and hydroxymethyl cellulose is 1:0.5:0.07.

[0050] Preparation Example 2-5 The difference from Preparation Example 2-1 is that the mass ratio of straw, modified diatomaceous earth and hydroxymethyl cellulose is 1:0.9:0.01.

[0051] Preparation Example 2-6 The difference from Preparation Example 2-1 is that no phenolic resin is added in the preparation method of modified diatomaceous earth.

[0052] Preparation Example 2-7 The difference from Preparation Example 2-1 is that no aloe vera extract is added in the preparation method of modified diatomaceous earth. Example

[0053] Example 1 An environmentally friendly termite trapping strip comprises the following raw materials: 0.5 kg of microcrystalline cellulose, 2 kg of sodium carboxymethyl cellulose, 0.5 kg of potassium sorbate, 2 kg of pine sawdust, 5 kg of cassava flour, 1 kg of xanthan gum, and 4 kg of termite killing microcapsules, measured by weight.

[0054] The killing microcapsule includes a capsule wall and a capsule core. The capsule core contains 3kg of flubendiamide, 4kg of diflubenzuron, 2kg of ammonium chloride, 20kg of petroleum ether, and 5kg of sodium dodecylbenzenesulfonate. In the capsule wall: 17kg modified chitosan, 10kg sodium alginate, 12kg modified corn straw powder, 2kg gum arabic, and 3kg sugarcane extract.

[0055] The preparation method of the environmentally friendly termite trap strip comprises the following steps: the preparation method of the termite killing microcapsule comprises: uniformly mixing triflumuron, diflubenzuron, ammonium chloride, petroleum ether and sodium dodecylbenzenesulfonate to obtain a capsule core; Modified chitosan, sodium alginate, modified corn straw, gum arabic, sugarcane extract and water are mixed to obtain capsule wall; capsule core, capsule wall and emulsifier are mixed, high pressure homogenized and spray dried to obtain killing microcapsules; The pressure of high-pressure homogenization is 30 MPa; the inlet air temperature of spray drying is 150°C, and the outlet air temperature is 100°C; the emulsifier is Tween-80; Microcrystalline cellulose, sodium carboxymethyl cellulose, potassium sorbate, pine sawdust, cassava flour, xanthan gum, miasma microcapsules and water were mixed and stirred for 30 minutes, pressed into shape and dried to obtain the trapping strips.

[0056] The drying temperature was controlled at 65°C, the drying time was 5 hours, and the height of the trapping strip was 1 cm.

[0057] The modified chitosan was prepared according to Preparation Example 1-1, and the modified corn straw powder was prepared according to Preparation Example 2-1.

[0058] Example 2 An environmentally friendly termite trapping strip, which differs from Example 1 in that it comprises the following raw materials: 1.5 kg of microcrystalline cellulose, 3 kg of sodium carboxymethyl cellulose, 1 kg of potassium sorbate, 4 kg of pine sawdust, 2 kg of cassava flour, 2 kg of xanthan gum, and 8 kg of termite killing microcapsules, measured by weight.

[0059] The microcapsules include capsule walls and capsule cores. The capsule cores contain 4kg of triflumuron, 6kg of diflubenzuron, 3kg of ammonium chloride, 25kg of petroleum ether, and 8kg of sodium dodecylbenzenesulfonate. In the capsule wall: 20kg modified chitosan, 13kg sodium alginate, 15kg modified corn straw powder, 5kg gum arabic, and 6kg sugarcane extract.

[0060] Example 3 An environmentally friendly termite trapping strip is different from Example 1 in that the modified chitosan is prepared as in Preparation Example 1-2.

[0061] Example 4 An environmentally friendly termite trapping strip is different from Example 1 in that the modified chitosan is prepared as in Preparation Examples 1-3.

[0062] Example 5 An environmentally friendly termite trapping strip is different from Example 1 in that the modified chitosan is prepared as in Preparation Examples 1-4.

[0063] Example 6 An environmentally friendly termite trapping strip is different from Example 1 in that the modified chitosan is prepared as in Preparation Example 1-5.

[0064] Example 7 An environmentally friendly termite trapping strip is different from Example 1 in that the modified chitosan is prepared as in Preparation Example 1-6.

[0065] Example 8 An environmentally friendly termite trapping strip is different from Example 1 in that the modified chitosan is prepared as in Preparation Example 1-7.

[0066] Example 9 An environmentally friendly termite trapping strip is different from Example 1 in that the modified chitosan is prepared as in Preparation Example 1-8.

[0067] Example 10 An environmentally friendly termite trapping strip is different from Example 1 in that the modified chitosan is prepared as in Preparation Example 1-9.

[0068] Example 11 An environmentally friendly termite trapping strip, which differs from Example 1 in that the modified corn straw powder adopts the preparation example 2-2.

[0069] Example 12 An environmentally friendly termite trapping strip is different from Example 1 in that the modified corn straw powder is prepared as in Preparation Example 2-3.

[0070] Example 13 An environmentally friendly termite trapping strip is different from Example 1 in that the modified corn straw powder is prepared as in Preparation Example 2-4.

[0071] Example 14 An environmentally friendly termite trapping strip is different from Example 1 in that the modified corn straw powder is prepared as in Preparation Example 2-5.

[0072] Example 15 An environmentally friendly termite trapping strip is different from Example 1 in that the modified corn straw powder is prepared as in Preparation Example 2-6.

[0073] Example 16 An environmentally friendly termite trapping strip is different from Example 1 in that the modified corn straw powder is prepared as in Preparation Example 2-7.

[0074] Comparative Example Comparative Example 1 An environmentally friendly termite trapping strip, which differs from Example 1 in that modified chitosan is not added.

[0075] Comparative Example 2 An environmentally friendly termite trapping strip is different from Example 1 in that an equal amount of chitosan is used instead of modified chitosan.

[0076] Comparative Example 3 An environmentally friendly termite trapping strip differs from Example 1 in that modified corn straw powder is not added.

[0077] Comparative Example 4 An environmentally friendly termite trapping strip is different from Example 1 in that the modified corn straw powder is replaced by an equal amount of corn straw powder.

[0078] Performance testing The trapping strips and killing microcapsules prepared in Examples 1-16 and Comparative Examples 1-4 were subjected to performance tests; Mechanical Strength Test: The tablet press was used to compress the microcapsules of the Examples and Comparative Examples at a pressure of 6 MPa to observe the damage of the microcapsules. The lower the damage rate, the higher the mechanical strength of the microcapsules.

[0079] Embedding efficiency: The microcapsules used in the examples and comparative examples were tested for their embedding efficiency. The embedding efficiency refers to the ratio of the amount of core material embedded in the microcapsule to the total amount of core material added during embedding. The higher the embedding efficiency, the greater the amount of core material embedded, and the better the effect. Embedding efficiency = (total mass of core material in the microcapsule - mass of core material on the microcapsule surface) / total mass of core material in the microcapsule × 100%; Dispersion stability: The miasa microcapsules of the embodiment and the comparative example were ultrasonically dispersed in a 0.05 mol / L sodium hydroxide aqueous solution at a weight ratio of 1:100, and left at room temperature for 10 days and 20 days, respectively, to observe the stability.

[0080] Insecticidal performance test: The location is the forest land of Dushan Village, Hong'an, Hubei Province. The environmentally friendly termite trapping strips prepared in the examples and comparative examples are tied around tree trunks with mud blankets or mud lines. The height of the tie is 60 cm from the ground. Two layers of 12 cm wide transparent tape are wrapped around the outside to prevent rain and moisture. The tree species is Pinus massoniana, and the target of prevention and control is black-winged termites. The trapping effect is tested.

[0081] Damage reduction rate = (damage rate before trapping - damage rate after trapping) / damage rate before trapping × 100%; Trapping effect = (hazard reduction rate of the area - hazard reduction rate of the control area) / (1 - hazard reduction rate of the control area) × 100%; test results are shown in Table 1.

[0082] Table 1 Test data of embodiments and comparative examples Combining the examples and the data in Table 1, it can be seen that the environmentally friendly termite trapping strips prepared in Examples 1-2, Example 5, Example 9, and Example 13 have good mechanical properties, stability, and trapping effects. Among them, the breakage rate of Example 1 is 1.9%. In the accelerated test, the stability is excellent after 10 days and 20 days, and no sedimentation occurs. The trapping effect is 95.23%, indicating that the killing microcapsules prepared in this application have excellent mechanical properties, are not easy to break, and have good stability, which can enable the insecticide to exert its efficacy for a longer time. The killing microcapsules can slowly release the drug, thereby extending the insecticidal time and having a high insecticidal efficiency.

[0083] In the preparation method of modified chitosan in Example 3, carbon nanotubes are not added. As can be seen from Table 1, compared with Example 1, the breakage rate is 3.1%. In the accelerated test, the stability is better after 10 days, and there is slight sedimentation after 20 days. The trapping effect is 87.45%, indicating that carbon nanotubes have good mechanical properties and repairability, and can fill cracks. Subsequently, it helps to improve the mechanical properties of the microcapsule wall and repair cracks, thereby prolonging the insecticidal effect of the microcapsules.

[0084] In the preparation method of modified chitosan in Example 4, modified silver nanofibers are not added. As can be seen from Table 1, compared with Example 1, the breakage rate is 3.9%. In the accelerated test, the stability is better after 10 days, and there is slight sedimentation after 20 days. The trapping effect is 81.78%, indicating that the modified silver nanofibers can be loaded on the surface and pores of carbon nanotubes. The carbon nanotubes loaded with modified silver nanofibers are mixed with chitosan, which improves the mechanical properties and antibacterial properties of chitosan. In addition, the cracks in chitosan are effectively repaired subsequently, thereby prolonging the efficacy time of the killing microcapsules.

[0085] Example 6 changes the mass ratio of chitosan, carbon nanotubes and modified silver nanofibers. As can be seen from Table 1, compared with Example 1, the breakage rate and the trapping effect performance are worse than those of Examples 1-2 and Example 5, but better than those of Examples 3-4, indicating that the modified silver nanofibers can be loaded on the surface of the carbon nanotubes, thereby improving the filling capacity of the carbon nanotubes, so that the carbon nanotubes loaded with modified silver nanofibers can be loaded in the network pores of chitosan, thereby improving the mechanical properties of chitosan, and subsequently making the capsule wall have better mechanical properties and repairability, and not easy to rupture.

[0086] In the preparation method of the modified silver nanofibers in Example 7, no PVP is added, and in the preparation method of the modified silver nanofibers in Example 8, no silane coupling agent is added. As can be seen from Table 1, compared with Example 1, the breakage rate is significantly increased. In the accelerated test, the stability is better after 10 days, and there is slight sedimentation after 20 days, and the trapping effect is significantly reduced, indicating that PVP has good biocompatibility, chemical stability and strong bonding ability, can adjust the viscosity of the system, can coat silver nanofibers, and contribute to the film-forming property of the capsule wall; the cross-linking modification of the silane coupling agent and PVP makes the silver nanofibers have better mechanical properties, which contributes to the subsequent improvement of the mechanical properties and film-forming property of the capsule wall.

[0087] In Example 10, the mass ratio of silver nanofibers, PVP and silane coupling agent was changed. As can be seen from Table 1, compared with Example 1, the breakage rate and the trapping effect performance were worse than those of Examples 1-2 and Example 9, but better than those of Examples 7-8, indicating that the silver nanofibers, PVP and silane coupling agent had a synergistic effect. The silane coupling agent was cross-linked and modified with PVP to coat the silver nanofibers, so that the silver nanofibers had better mechanical properties, which was helpful to subsequently obtain a capsule wall with better mechanical properties and film-forming properties.

[0088] In the preparation method of modified corn straw powder in Example 11, modified diatomaceous earth is not added. As can be seen from Table 1, compared with Example 1, the breakage rate is 3.8%. In the accelerated test, the stability is better after 10 days, and there is slight sedimentation after 20 days. The trapping effect is 82.31%, indicating that the modified diatomaceous earth has good adsorption and filling properties. The straw particles can be loaded on the surface and pores of the modified diatomaceous earth, thereby improving the mechanical properties of the straw particles, which will help to improve the corresponding properties of the capsule wall later.

[0089] In the preparation method of modified corn straw powder in Example 12, no hydroxymethyl cellulose is added. As can be seen from Table 1, compared with Example 1, the breakage rate is 3.2%. In the accelerated test, the stability is better after 10 days, and there is slight sedimentation after 20 days. The trapping effect is 86.42%, indicating that methyl cellulose makes the modified diatomaceous earth and straw particles adhere tightly, and is subsequently applied to the capsule wall to effectively fill the gaps in the capsule wall and improve the mechanical properties of the capsule wall.

[0090] Example 14 changes the mass ratio of straw, modified diatomaceous earth and hydroxymethyl cellulose. As can be seen from Table 1, compared with Example 1, the breakage rate and the trapping effect performance are worse than those of Examples 1-2 and Example 13, but better than those of Examples 11-12, indicating that the modified diatomaceous earth has good adsorption and filling properties. The straw particles are loaded in the pores of the modified diatomaceous earth, and the hydroxymethyl cellulose makes the straw particles and the modified diatomaceous earth adhere tightly, thereby improving the performance stability of the modified straw powder. The subsequent filling in the capsule wall improves the mechanical properties of the capsule wall, which helps to kill the bactericidal persistence of the microcapsules.

[0091] In the preparation methods of modified diatomaceous earth in Examples 15-16, no phenolic resin and aloe extract were added. As can be seen from Table 1, compared with Example 1, the breakage rate was significantly increased and the trapping effect was significantly reduced, indicating that the phenolic resin modified diatomaceous earth improved the adhesion of the diatomaceous earth, which subsequently helped the diatomaceous earth to adhere to the straw particles. The aloe extract has good antioxidant properties and improves the biological activity of each component.

[0092] Comparative Example 1 does not add modified chitosan. As can be seen from Table 1, compared with Example 1, the breakage rate is 9.7%. In the accelerated test, there is sedimentation after 10 days, and serious sedimentation after 20 days. The trapping effect is 60.23%, indicating that the modified chitosan has good mechanical effect, film-forming property and biocompatibility, has good sustained-release effect, and improves the film-forming property and mechanical properties of the system.

[0093] Comparative Example 3 does not add modified corn straw powder. As can be seen from Table 1, compared with Example 1, the breakage rate is 9.1%. In the accelerated test, there is sedimentation after 10 days and severe sedimentation after 20 days. The trapping effect is 63.98%, indicating that the modified corn straw powder has more fibers and can be loaded in the cross-linked structure formed by modified chitosan and sodium alginate, thereby improving the mechanical properties of the system and making the prepared capsule wall have a better embedding rate.

[0094] Comparative Example 2 and Comparative Example 4 respectively replace the modified chitosan with an equal amount of chitosan and replace the modified corn straw powder with an equal amount of corn straw powder. As can be seen from Table 1, compared with Example 1, the breakage rate and the trapping effect are significantly worse than those of Examples 1-2, but better than Comparative Example 1 and Comparative Example 3. In the accelerated test, it is stable after 10 days and slightly precipitates after 20 days, indicating that the modified chitosan and modified corn straw powder prepared in this application have good mechanical properties, so that the capsule wall has a good embedding rate, and can subsequently kill insects for a long time.

[0095] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed, but as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. An environmentally friendly termite trapping strip, characterized in that: The raw materials include: microcrystalline cellulose, sodium carboxymethyl cellulose, potassium sorbate, pine sawdust, cassava flour, xanthan gum, and miasma microcapsules; The killing microcapsule comprises a capsule wall and a capsule core, wherein the capsule core comprises the following raw materials: triflumuron, diflubenzuron, ammonium chloride, petroleum ether, and sodium dodecylbenzenesulfonate; The capsule wall comprises the following raw materials: modified chitosan, sodium alginate, modified corn straw powder, gum arabic and sugarcane extract.

2. The environmentally friendly termite trapping strip according to claim 1, characterized in that: According to weight parts, 0.5-1.5 parts of microcrystalline cellulose, 2-3 parts of sodium carboxymethyl cellulose, 0.5-1 part of potassium sorbate, 2-4 parts of pine sawdust, 2-5 parts of cassava flour, 1-2 parts of xanthan gum, and 4-8 parts of miasma microcapsules; The capsule core contains 3-4 parts of triflumuron, 4-6 parts of diflubenzuron, 2-3 parts of ammonium chloride, 20-25 parts of petroleum ether, and 5-8 parts of sodium dodecylbenzenesulfonate; The capsule wall contains: 17-20 parts of modified chitosan, 10-13 parts of sodium alginate, 12-15 parts of modified corn straw powder, 2-5 parts of gum arabic, and 3-6 parts of sugarcane extract.

3. The environmentally friendly termite trapping strip according to claim 1, characterized in that: The preparation method of the modified chitosan comprises the following steps: (1) Dispersing chitosan in acetic acid solution, adding epichlorohydrin, and stirring at 50-55°C for 2-3 hours to obtain a reaction solution; (2) dispersing carbon nanotubes in deionized water, adding modified silver nanofibers and N,N-dimethylformamide, and stirring at a temperature of 60-65°C for 1-2 hours to obtain a mixed solution; (3) The reaction solution of step (1) and the mixed solution of step (2) are mixed, NaOH solution is added, the pH is adjusted to 10-11, stirred for 1-2 hours, cooled to 20-30°C, filtered, washed, and vacuum dried to obtain modified chitosan.

4. The environmentally friendly termite trapping strip according to claim 3, characterized in that: The mass ratio of the chitosan, carbon nanotubes and modified silver nanofibers is 1:0.6-0.9:0.2-0.

4.

5. The environmentally friendly termite trapping strip according to claim 3, characterized in that: The preparation method of the modified silver nanofiber comprises the following steps: dispersing the silver nanofiber in deionized water, adding lauric acid, PVP and a silane coupling agent, and ultrasonicating at a temperature of 60-65° C. for 1-2 hours to obtain the modified silver nanofiber.

6. The environmentally friendly termite trapping strip according to claim 5, characterized in that: The mass ratio of the silver nanofiber, PVP and silane coupling agent is 1:0.02-0.05:0.1-0.

3.

7. The environmentally friendly termite trapping strip according to claim 1, characterized in that: The preparation method of the modified corn straw powder comprises the following steps: (1) Crush the straw, sieve it, and then disperse it in a sodium hydroxide solution. Stir it at 80-85°C for 2-3 hours. Filter it, wash it with water, and then disperse it in deionized water. Add fish meal and stir it evenly to obtain a mixed solution. (2) Dispersing the modified diatomaceous earth in deionized water, adding the mixed solution of step (1), black fungus extract, sodium lauryl sulfate and hydroxymethyl cellulose, stirring evenly at 70-75° C., filtering, drying and grinding to obtain modified corn straw powder.

8. The environmentally friendly termite trapping strip according to claim 7, characterized in that: The mass ratio of the straw, modified diatomaceous earth and hydroxymethyl cellulose is 1:0.2-0.5:0.07-0.

09.

9. The environmentally friendly termite trapping strip according to claim 7, characterized in that: The preparation method of the modified diatomaceous earth comprises the following steps: grinding and sieving the diatomaceous earth, calcining the diatomaceous earth at a temperature of 300-320°C for 2-3 hours, dispersing the diatomaceous earth in a tartaric acid solution, stirring the diatomaceous earth for 1-2 hours, filtering the diatomaceous earth, dispersing the diatomaceous earth in deionized water, adding phenolic resin, aloe extract and hexaflumuron, stirring the diatomaceous earth uniformly, and drying the diatomaceous earth.

10. The method for preparing an environmentally friendly termite trapping strip according to claim 1, characterized in that: The steps include: The preparation method of the microcapsule of the invention comprises the following steps: uniformly mixing triflumuron, diflubenzuron, ammonium chloride, petroleum ether and sodium dodecylbenzenesulfonate to obtain a capsule core; Modified chitosan, sodium alginate, modified corn straw, gum arabic, sugarcane extract and water are mixed to obtain a capsule wall; The capsule core, capsule wall and emulsifier are mixed, homogenized under high pressure and spray-dried to obtain the killing microcapsules; Mix microcrystalline cellulose, sodium carboxymethyl cellulose, potassium sorbate, pine sawdust, cassava flour, xanthan gum, miasma microcapsules and water and stir for 25-30 minutes, press into shape, and dry to obtain the trapping strips.

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