Insecticidal suspension, preparation method and application

Abstract

The invention discloses an insecticidal suspension which comprises the following components in percentage by weight: 5-20% of chlorfenapyr, 10-40% of lufenuron, 1-5% of a modified rosin polyether modifier, 0.5-10% of sodium polycarboxylate, 0.1-2% of an organic silicon synergist, 0.1-1% of a light stabilizer, 0.3-1% of an anti-crystallization agent, 0.1-0.5% of nano titanium dioxide and the balance of deionized water. By adding the complexing agent, the settling suspension resistance and the photolysis resistance of the insecticidal suspension are improved through the mutual synergistic effect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of pesticide preparation, in particular to a kind of insecticidal suspension, preparation method and application. BACKGROUND

[0002] In the prior art, lufenuron, as a new generation of substituted urea insecticide, hinders the molting of larvae by inhibiting the activity of chitin synthase, and shows long-acting control advantage in controlling leaf-eating caterpillars of fruit trees; while chlorfenapyr, with pyrazole ring structure, inhibits the mitochondrial electron transport chain, and has a rapid knockdown effect on pests. When the two are used together to control lepidopteran pests such as Spodoptera exigua and vegetable leaf moth, etc.

[0003] The prior art CN115553297A discloses a kind of insecticidal suspension and its suspension agent, preparation method and application, which discloses a technical solution that lufenuron and chlorfenapyr are compounded at a weight ratio of 1:(2-10), a dispersing agent is compounded by modifying rosin polyether modifier and sodium polycarboxylate (such as SP-2700), and functional additives such as white carbon black and magnesium aluminum silicate are used. Although the storage stability of the suspension agent is improved to some extent, there are still technical defects.

[0004] For example, the experimental results show that when conventional 600-mesh white carbon black (particle size about 20 μm) is used as an anti-settling aid, the particle size D90 of the suspension agent prepared by a sand mill is 2.8 μm, and the sedimentation volume ratio reaches 35% after 14 days of hot storage at 54℃, and the particle size increases to 5.6 μm. This is because the three-dimensional network pores formed by the white carbon black are relatively large, and cannot effectively bind the micron-sized pesticide particles, with a settling speed of 0.1 mm / h, leading to particle aggregation. At the same time, the pyrazole ring structure of chlorfenapyr has a strong absorption peak in the ultraviolet light region of 320-400 nm, and the free radicals generated by photolysis can attack the ether bond structure in the dispersing agent molecules, reducing the zeta potential of the modified rosin polyether modifier from about 32 mV to about 15 mV, and further reducing the charge repulsion energy barrier between particles, thereby exacerbating the aggregation.

[0005] More importantly, without the introduction of a light shielding agent, the light transmittance of the suspension agent increases after particle aggregation caused by settling, and the penetration depth of ultraviolet light increases, leading to a shortening of the chlorfenapyr photolysis half-life, forming a vicious cycle of "settling-photolysis-dispersing agent failure-exacerbating settling". Field test data show that the control efficiency of the compound suspension agent is 92.47% 7 days after application, but the control efficiency decreases to 80.77% 14 days after application, and the active ingredient loss is more than 35% in 24 h, and the resistance factor of Spodoptera exigua to chlorfenapyr increases to 12.7 times after 8 generations of continuous use, exposing the shortcomings of the prior art in terms of anti-settling, light stability improvement and resistance management. SUMMARY

[0006] The present application intends to provide a kind of insecticidal suspension, preparation method and application, by adding complexing agent, synergistic effect improves the anti-settling suspension, anti photolysis performance of insecticidal suspension.

[0007] In order to achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0008] An insecticidal suspension, comprising the following components by weight percentage: 5-20% of imidacloprid, 10-40% of clofentezine, 1-5% of modified rosin polyether modifier, 0.5-10% of polycarboxylate sodium salt, 0.1-2% of silicone synergist, 0.1-1% of light stabilizer, 0.3-1% of anti-crystallization agent, 0.1-0.5% of nano titanium dioxide, and the rest is deionized water.

[0009] Optimally, the polycarboxylate sodium salt is SP-2700 or similar polycarboxylate salt dispersant, and the suspension further comprises 0.1-2% of silicone synergist by weight percentage, which is polyether modified trisiloxane or similar structure surfactant.

[0010] In some embodiments, the nano titanium dioxide has a particle size of 30-100 nm.

[0011] Additionally, the weight ratio of imidacloprid to clofentezine is 1:2-5.

[0012] Optimally, the light stabilizer is a complex of hindered amine light stabilizer and benzotriazole compound, with a weight ratio of 1:0.5-2.

[0013] In some embodiments, the hindered amine light stabilizer comprises hindered amine 770 and hindered amine 662, and the benzotriazole compound comprises UV-P and 2-(5-chloro-2H-benzotriazole-2-yl)-4-methyl-6-(tert-butyl) phenol.

[0014] Optimally, the anti-crystallization agent is a complex of hydroxypropyl-β-cyclodextrin and polyethylene glycol, with a weight ratio of 1:0.5-2.

[0015] A preparation method of a suspension, wherein imidacloprid, clofentezine and nano titanium dioxide are mixed, modified rosin polyether modifier, polycarboxylate sodium salt and deionized water are added, and then high-speed shearing dispersion is performed at 10,000-20,000 rpm for 20-40 min, and then high-pressure homogenization is performed 2-4 times at a pressure of 100-200 MPa to obtain a nano suspension.

[0016] Application of a kind of insecticidal suspension in preventing and treating Lepidoptera pests.

[0017] Working principle and beneficial effects of the present application:

[0018] As a mitochondrial electron transport inhibitor, chlorfenapyr paralyzes pests by blocking ATP synthesis, making their neuromuscular system paralyzed. Lufenuron inhibits chitin synthetase, interfering with the molting of pests. When the two are combined, synergistic insecticidal effects are produced due to different action sites, and the evolution of resistance is delayed.

[0019] The modified rosin polyether modifier and the sodium polycarboxylate (such as SP-2700) as dispersants, the former adsorbs the raw drug particles through the hydrophobic rosin skeleton, and forms a 5-10 nm steric hindrance layer with the hydrophilic polyether chain, and the latter provides negative charges as a comb polymer and enhances the steric stability. After the two are combined, a double-stabilizing mechanism of charge repulsion and steric hindrance is formed, making the particle size D90 of the suspension ≤120 nm, the sedimentation volume ratio ≤2% after 14 days of hot storage at 54°C, and the particle size growth rate only 5%, which is more than 80% higher than that of a single dispersant in improving stability.

[0020] The organosilicon synergist (such as polyether-modified trisiloxane) reduces the surface tension due to its unique trisiloxane structure, enabling the pesticide solution to achieve super-spreading penetration. At the same time, it synergizes with the modified rosin polyether modifier, which destroys the waxy layer of the pest's cuticle, and the former accelerates the penetration of the pesticide through the spiracles and body wall into the pest's body, thereby increasing the mortality rate.

[0021] The nano-titanium dioxide (10-100 nm) and the light stabilizer form a synergistic anti-photolysis system: nano-titanium dioxide reflects / scatters 280-400 nm ultraviolet light, hindered amine (such as Tinuvin770) captures photolysis free radicals, and benzotriazole (such as UV-P) absorbs ultraviolet light and releases energy in the form of heat. The three together extend the photolysis half-life of chlorfenapyr from the existing technology of 4.2 h to more than 15 h, greatly improve the 24 h active ingredient retention rate, and the surface of nano-titanium dioxide is coated with sodium polycarboxylate to form a protective layer, further inhibiting the damage of photolysis products to dispersants and maintaining system stability.

[0022] The anti-crystallization agent (hydroxypropyl-β-cyclodextrin + polyethylene glycol) synergistically inhibits crystallization at the molecular level: the cavity of hydroxypropyl-β-cyclodextrin precisely includes the molecules of chlorfenapyr / lufenuron, preventing the formation of crystal nuclei, and the long-chain molecules of polyethylene glycol insert into the crystal lattice gap to hinder crystal growth. The combination of the two reduces the crystallization rate to ≤0.3% at 0°C for 14 days, which is more than 70% lower than that of a single component, and improves the dispersibility of light stabilizers.

[0023] In summary, through the synergistic effects of dispersion stability, penetration enhancement, photolysis inhibition, and crystallization blocking, the anti-settling ability is improved, the photolysis half-life is extended, the low-temperature crystallization rate is reduced, and the efficacy duration is extended, and it is highly effective against both sensitive and resistant pests. The problems of poor stability, rapid efficacy decay, and rapid development of resistance in traditional suspensions are systematically solved. DETAILED DESCRIPTION

[0024] The following is further described in detail through specific embodiments:

[0025] An insecticidal suspension, comprising the following components by weight percentage: imicyaflo 5-20%, lufenuron 10-40%, modified rosin polyether modifier 1-5%, polycarboxylic acid sodium salt 0.5-10%, silicone synergist 0.1-2%, light stabilizer 0.1-1%, anti-crystallization agent 0.3-1%, nano-titanium dioxide 0.1-0.5%, and the balance being deionized water.

[0026] Mix imicyaflo, lufenuron and nano-titanium dioxide, add modified rosin polyether modifier, polycarboxylic acid sodium salt and deionized water, disperse at 10000 rpm for 30 min, and then pass through a high-pressure homogenizer for 3 times at a pressure of 150 MPa to obtain a nano-suspension.

[0027] Example 1: An insecticidal suspension, comprising the following components by weight percentage: imicyaflo 5%, lufenuron 10%, modified rosin polyether modifier 1%, polycarboxylic acid sodium salt 0.5%, silicone synergist 0.1%, light stabilizer 0.1%, anti-crystallization agent 0.3%, nano-titanium dioxide 0.1% (particle size 30 nm), and the balance being deionized water.

[0028] Among them, the polycarboxylic acid sodium salt is SP-2700, the silicone synergist is polyether modified trisiloxane, the light stabilizer is a compound of hindered amine 770 and UV-P with a weight ratio of 1:0.5, and the anti-crystallization agent is a compound of hydroxypropyl-β-cyclodextrin and polyethylene glycol with a weight ratio of 1:0.5.

[0029] Example 2: The difference from Example 1 is that imicyaflo is 10%, lufenuron is 20%, modified rosin polyether modifier is 3%, polycarboxylic acid sodium salt is 5%, silicone synergist is 1%, light stabilizer is 0.5%, anti-crystallization agent is 0.7%, and nano-titanium dioxide is 0.3%.

[0030] Example 3: The difference from Example 1 is that imicyaflo is 20%, lufenuron is 40%, modified rosin polyether modifier is 5%, polycarboxylic acid sodium salt is 10%, silicone synergist is 2%, light stabilizer is 1%, anti-crystallization agent is 1%, and nano-titanium dioxide is 0.5%.

[0031] Example 4: The difference from Example 2 is that the light stabilizer is a compound of hindered amine 770 and UV-P with a weight ratio of 1:1.

[0032] Example 5: The difference from Example 2 is that the light stabilizer is a compound of hindered amine 770 and UV-P with a weight ratio of 1:2.

[0033] Example 6: The difference from Example 2 is that the light stabilizer is a compound of Hostanox® 662 and 2-(5-chloro-2H-benzotriazol-2-yl)-4-methyl-6-(tert-butyl)phenol, the weight ratio is 1:0.5.

[0034] Example 7: The difference from Example 2 is that the light stabilizer is a compound of Hostanox® 662 and 2-(5-chloro-2H-benzotriazol-2-yl)-4-methyl-6-(tert-butyl)phenol, the weight ratio is 1:1.

[0035] Example 8: The difference from Example 2 is that the light stabilizer is a compound of Hostanox® 662 and 2-(5-chloro-2H-benzotriazol-2-yl)-4-methyl-6-(tert-butyl)phenol, the weight ratio is 1:2.

[0036] Example 9: The difference from Example 2 is that the anti-crystallization agent is a compound of hydroxypropyl-β-cyclodextrin and polyethylene glycol, the weight ratio is 1:1.

[0037] Example 10: The difference from Example 2 is that the anti-crystallization agent is a compound of hydroxypropyl-β-cyclodextrin and polyethylene glycol, the weight ratio is 1:2.

[0038] Example 11: The difference from Example 2 is that the silicone synergist is cancelled, the anti-crystallization agent, the light stabilizer, and the nano-titanium dioxide are retained.

[0039] Example 12: The difference from Example 2 is that the light stabilizer is cancelled, the silicone synergist, the anti-crystallization agent, and the nano-titanium dioxide are retained.

[0040] Example 13: The difference from Example 2 is that the anti-crystallization agent is cancelled, the silicone synergist, the light stabilizer, and the nano-titanium dioxide are retained.

[0041] Example 14: The difference from Example 2 is that the nano-titanium dioxide is cancelled, the silicone synergist, the anti-crystallization agent, and the light stabilizer are retained.

[0042] Example 15: The difference from Example 2 is that the nano-titanium dioxide and the silicone synergist are cancelled, the anti-crystallization agent and the light stabilizer are retained.

[0043] Example 16: The difference from Example 2 is that the anti-crystallization agent and the light stabilizer are cancelled, the nano-titanium dioxide and the silicone synergist are retained.

[0044] Example 17: The difference from Example 2 is that the nano-titanium dioxide is 0.1% (particle size 60 nm).

[0045] Example 18: The difference from Example 2 is that the nano-titanium dioxide is 0.1% (particle size 100 nm).

[0046] Controlled drug:

[0047] Blank control: deionized water

[0048] Prior art control 1: commercially available 20% buprofezin suspension concentrate (without lufenuron);

[0049] Prior art control 2: commercially available 10% lufenuron suspension concentrate (without buprofezin);

[0050] Prior art control 3: CN115553297A Example 1 formulation (buprofezin + lufenuron + conventional adjuvants).

[0051] Test insects: Spodoptera exigua 3rd instar larvae (sensitive strain and resistant strain);

[0052] Test crops: Brassica oleracea (3-4 leaf stage).

[0053] (1) Physical stability test Particle size distribution: D10, D50, D90 and PDI values were determined by laser particle size analyzer (Malvern Mastersizer 3000); Suspension rate: GB / T 14825-2006 "Pesticide Suspension Rate Determination Method"; Heat storage stability: stored at 54℃±2℃ for 14 days, and the water separation rate and particle size change rate were determined; Low temperature stability: stored at 0℃ for 7 days, and the crystallization was observed and the crystallization rate was determined. (2) Photolysis resistance test UV irradiation: irradiated by UV lamp (365nm, intensity 5000μW / cm 2 ) for 24h; HPLC analysis: the photolysis residual rates of buprofezin and lufenuron were determined; Photolysis kinetics: the photolysis half-life (t1 / 2) and degradation rate constant (k) were calculated. (3) Biological activity test Indoor toxicity determination: leaf immersion method, LC 50 and co-toxicity coefficient (CTC) were calculated; Penetration efficiency: the penetration amount of the agent in the insect body wall was determined by fluorescence labeling method; Persistence period determination: mortality was investigated at 1, 3, 7, 14, 21 days after treatment. (4) Field control effect test Test design: randomized block design, 4 times of repetition, plot area 20m 2 ; Application method: knapsack sprayer, dosage 1000 times dilution; Investigation method: pre-treatment insect population investigation, post-treatment live insect number investigation at 3, 7, 14 days.

[0054] The following data are shown in Tables 1-Table.

[0055] Table 1-Physical stability data

[0056]

[0057]

[0058]

[0059] Table 2-Photolysis resistance data

[0060]

[0061]

[0062] Table 3 - Bioactivity data

[0063]

[0064]

[0065] Table 4 - Field efficacy trials

[0066]

[0067]

[0068] From Table 1, physical stability data analysis:

[0069] (1) When the sodium polycarboxylate salt increased from 0.5% (Example 1) to 10% (Example 3), the particle size D90 decreased from 180 nm to 100 nm, the heat storage growth rate decreased from 8% to 4%, and the suspension rate increased from 95% to 99%. High concentration (10%) has a significant stabilizing effect on high content of technical material (spinetoram 20% + lufenuron 40%).

[0070] (2) Light stabilizer ratio variable

[0071] Example 4 (light stabilizer 1:1) compared with Example 2 (1:0.5), the particle size D90 increased from 120 nm to 125 nm, the heat storage growth rate increased from 5% to 6%, and the suspension rate decreased from 98% to 97%. The adjustment of the ratio of light stabilizers has a weak effect on physical stability, as the dispersion synergy of sodium polycarboxylate (5%) and modified rosin polyether (3%) dominates, proving that the light stabilizer compound ratio mainly affects photolysis resistance and has no significant interference with dispersion stability.

[0072] (3) Light stabilizer variety replacement (Examples 6-8)

[0073] Example 6 (hindered amine 662 + chlorobenzotriazole) has a particle size D90 of 122 nm, a heat storage growth rate of 5%, and is equivalent to Example 2; Example 8 (light stabilizer 1:2) has a particle size D90 of 123 nm and a suspension rate of 97%, which is slightly lower than Example 2. Light stabilizers of the same structure (such as 662 replacing 770) do not affect dispersion stability, verifying the functional equivalence of "compounds of the same type"; the light stabilizer 1:2 ratio does not exceed the dispersion agent synergy threshold, and the stability still meets the requirements.

[0074] (4) Anti-crystallization agent ratio

[0075] Example 9 (anti-crystallizer 1:1) 24h residual rate 89%, consistent with Example 2; Example 10 (1:2) residual rate 89%, photolytic product species still 1. Anti-crystallizer indirectly reduces photolytic reaction sites by inhibiting crystal growth, but has no direct effect on photolytic kinetics.

[0076] (5) absence of silicone synergist

[0077] Example 11 particle size D90 = 150 nm, thermal storage growth rate 12%, suspension rate 95%, crystallization rate 0.5%, all worse than Example 2, but better than prior art control 1 (D90 = 850 nm, crystallization rate 15%). It shows that the silicone synergist mainly affects the penetration efficiency, and has a secondary effect on the dispersion stability. Its absence leads to a slight increase in inter-particle interaction, but the dispersant synergy can still maintain basic stability.

[0078] (6) absence of light stabilizer (Example 12)

[0079] Example 12 imicyafos t1 / 2 = 8.0h, residual rate 60%, photolytic product species increased to 3, close to control 3 (t1 / 2 = 7.5h). It shows that the light stabilizer is the core component of photolytic protection. Its absence leads to the difficulty of "nano-TiO2 physical shielding", and the photolytic inhibition rate drops from 89% to 60%. This verifies the necessity of the triple light stabilizing mechanism.

[0080] (7) absence of anti-crystallizer (Example 13)

[0081] Example 13 imicyafos t1 / 2 = 15.2h, residual rate 89%, consistent with Example 2, photolytic product species still 1. It shows that the anti-crystallizer does not participate in photolytic protection, and its absence only affects the storage stability, without interfering with the light stabilizing synergy system, proving the modular design of multi-component synergy.

[0082] (8) absence of nano-titanium dioxide (Example 14)

[0083] Example 14 imicyafos t1 / 2 = 9.5h, residual rate 68%, photolytic inhibition rate 73%, down 18% from Example 2. It shows that the physical shielding of nano-titanium dioxide is the basis of light stabilizing synergy. Its absence leads to the direct exposure of light stabilizers to ultraviolet light, and the efficiency of free radical capture decreases, verifying the hierarchical synergy of "shielding-capture-transfer".

[0084] (9) absence of dual components (Example 15)

[0085] Example 15's imidacloprid t1 / 2 = 7.0h, residual rate 50%, close to control 2 (t1 / 2 = 5.2h), photoproduct species increased to 4. Illustrates that the dual absence of nano-TiO2 and organosilicon completely invalidates the synergistic effect of light stability, proving that the absence of core components will cause a cliff-like drop in performance.

[0086] (10) Nano-TiO2 particle size (Examples 17-18)

[0087] Example 17 (60nm) imidacloprid t1 / 2 = 15.0h, Example 18 (100nm) t1 / 2 = 14.5h, both slightly lower than Example 2 (15.2h).

[0088] Illustrates that 30nm nano-TiO2 has the optimal light reflection efficiency, 60-100nm has a decrease of about 5% in light shielding efficiency due to the decrease in specific surface area, but still meets the light stability requirements, proving the rationality of the 10-100nm particle size range.

[0089] Comparison with prior art controls:

[0090] Prior art control 1 / 2 (single agent) particle size > 850nm, crystallization rate > 15%, due to the lack of dispersion synergistic mechanism; control 3 (CN115553297A) particle size 550nm, crystallization rate 8%, still significantly higher than the present application (crystallization rate 0.3%).

[0091] Proves that the present application, through the ternary synergy of "modified rosin polyether modifier + sodium polycarboxylate + nano-TiO2", refines the particle size by 78% and reduces the crystallization rate by 96%.

[0092] Analysis of photolysis resistance data from Table 2:

[0093] (1) Active ingredient concentration gradient (Examples 1-3)

[0094] Example 1 (total content 15%) imidacloprid t1 / 1 = 12.0h, Example 3 (total content 60%) t1 / 2 = 14.8h, both lower than Example 2 (15.2h). High content of active ingredient (60%) due to the simultaneous increase in the content of nano-TiO2 (0.5%), the light reflection efficiency is enhanced, and the t1 / 2 is close to that of Example 2; low content system (15%) due to the insufficient relative concentration of light stabilizer, the photolysis resistance is slightly weaker, proving the "concentration-shielding" synergy of light stabilizer and nano-TiO2.

[0095] (2) Light stabilizer compounding ratio (Examples 4-5)

[0096] BHT: UV-P from 1 :0.5 (Example 2) to 1 :1 (4), 1 :2 (5), imicyafos t1 / 2 from 15.2 h to 14.5 h, 13.8 h, 24 h residual from 89% to 87%, 85%. At 1 :0.5, the hindered amine radical capture rate and the benzotriazole energy transfer efficiency reached a balance, and the excess benzotriazole would compete for the UV light absorption site, weakening the synergistic effect.

[0097] (3) Light stabilizer variety replacement (Examples 6-8)

[0098] Replacing 770 + UV-P with BHT + 2-(5-chlorobenzotriazole), imicyafos t1 / 2 remained 15.0 h, residual 88%, equivalent to the original system. Light stabilizers of similar structure (such as the piperidine ring structure of 662 and 770) have functional equivalence.

[0099] (4) Anti-crystallization agent ratio (Examples 9-10)

[0100] Example 9 (anti-crystallization agent 1 :1) 24 h residual 89%, consistent with Example 2; Example 10 (1 :2) residual 89%, the photolytic product species remained 1. It is shown that the anti-crystallization agent indirectly reduces the photolytic reaction site by inhibiting crystal growth.

[0101] (5) Silicone synergist absence (Example 11)

[0102] Example 11 imicyafos t1 / 2 = 15.0 h, residual 88%, close to Example 2.

[0103] (6) Light stabilizer absence (Example 12)

[0104] Example 12 imicyafos t1 / 2 = 8.0 h, residual 60%, the photolytic product species increased to 3, close to Control 3 (t1 / 2 = 7.5 h). It is shown that the light stabilizer is the core component of photolytic protection, and its absence leads to the difficulty of “nano-TiO2 physical shielding” alone, and the photolytic inhibition rate drops from 89% to 60%, verifying the necessity of the triple light stabilizing mechanism.

[0105] (7) Anti-crystallization agent absence (Example 13)

[0106] Example 13 imicyafos t1 / 2 = 15.2 h, residual 89%, consistent with Example 2, and the photolytic product species remained 1.

[0107] (8) Nano-titanium dioxide absence (Example 14)

[0108] Example 14's imidacloprid t1 / 2 = 9.5h, residual rate 68%, photolysis inhibition 73%, 18% lower than Example 2. Illustrates that the physical shielding of nano-Ti02 is the basis of the synergistic photostabilization, its absence results in direct exposure of the photostabilizer to UV light, and the efficiency of free radical capture decreases.

[0109] (9) Dual component absence (Example 15)

[0110] Example 15's imidacloprid t1 / 2 = 7.0h, residual rate 50%, close to control 2 (t1 / 2 = 5.2h), photolytic product species increased to 4. Illustrates that the dual absence of nano-Ti02 and organosilicon completely invalidates the synergistic photostabilization, proving that the absence of core components will result in a cliff-like performance decline.

[0111] (9) Nano-Ti02 particle size (Examples 17-18)

[0112] Example 17 (60nm) imidacloprid t1 / 2 = 15.0h, Example 18 (100nm) t1 / 2 = 14.5h, both slightly lower than Example 2 (15.2h).

[0113] 30nm nano-Ti02 has the best light reflection efficiency, 60-100nm due to the decrease in specific surface area, the light shielding efficiency decreases by about 5%, but still meets the photostabilization requirements, proving the reasonable inclusiveness of 10-100nm particle size range.

[0114] The photolytic half-life of the prior art controls 1 / 2 is < 5.2h, control 3 (single nano-Ti02 shielding) inhibition rate 65%; the present application through "nano-Ti02 reflection + hindered amine capture + benzotriazole transfer" triple synergy, the inhibition rate is increased to 89%, the half-life is extended to 15.2h.

[0115] Analysis from Table 3

[0116] (1) Active ingredient ratio (Examples 1-3)

[0117] Imidacloprid: Lufenuron from 1:2 (Example 2) to 1:2 (Example 3, 20%:40%), sensitive strain LC 50 From 0.8mg / L to 0.7mg / L, CTC from 156 to 160, efficacy from 90% to 92%.

[0118] (2) Photostabilizer ratio (Examples 4-5)

[0119] Example 4 (1:1) sensitive strain LC 50 = 0.85mg / L, resistant LC 50 = 8.5mg / L, CTC = 150, slightly lower than Example 2 (156); Example 5 (1:2) LC50 = 0.9 mg / L, CTC = 145.

[0120] When the stabilizer ratio deviates from 1:0.5, the mitochondrial inhibition efficiency of imicyafos decreases slightly due to accelerated photolysis, resulting in a small decrease in toxicity synergy, but it is still significantly better than control 3 (CTC = 130).

[0121] (3) Light stabilizer variety replacement (Examples 6-8)

[0122] LC of Example 6 (662 + chlorobenzotriazole) 50 = 0.82 mg / L, CTC = 153, equivalent to Example 2; LC of Example 8 (1:2) 50 = 0.85 mg / L, CTC = 150.

[0123] Replacing the same type of light stabilizer does not affect the toxicity synergy, verifying the "mechanism equivalence"; the light stabilizer 1:2 ratio does not break through the metabolic inhibition threshold, and the toxicity remains efficient.

[0124] (4) Anti-crystallization agent ratio (Examples 9-10)

[0125] LC of Example 9 (1:1) 50 = 0.8 mg / L, CTC = 156, consistent with Example 2; LC of Example 10 (1:2) 50 = 0.8 mg / L, 90% control effect.

[0126] The anti-crystallization agent indirectly ensures the stability of the toxicity by maintaining the uniform dispersion of the pesticide, and the change in its ratio does not directly affect the toxicity of the active ingredient, proving the "indirect synergy of anti-crystallization-toxicity".

[0127] (5) Light stabilizer absence (Example 12)

[0128] LC of sensitive strain of Example 12 50 = 1.0 mg / L, resistant LC 50 = 10 mg / L, CTC = 140, 80% control effect, 10% lower than Example 2.

[0129] The absence of light stabilizers leads to accelerated photolysis of imicyafos, and the effective concentration decays quickly. Although the penetration efficiency remains at 78%, the toxicity synergy is weakened due to the loss of active ingredients, verifying the "transmission synergy of light-toxicity".

[0130] (6) Anti-crystallization agent absence (Example 13)

[0131] LC of Example 13 50 = 0.8 mg / L, CTC = 156, 90% control effect, consistent with Example 2, only the low-temperature crystallization rate increases.

[0132] The anti-crystallization agent does not participate in the synergism of toxicity, and its absence does not affect the penetration and action mechanism of the active ingredient, proving the independence of the "anti-crystallization" function.

[0133] (7) Nanometer titanium dioxide deficiency (Example 14)

[0134] Sensitive strain LC of Example 14 50 = 1.2 mg / L, resistant LC 50 = 12 mg / L, CTC = 130, equivalent to control 3, control effect 65%.

[0135] The absence of nanometer titanium dioxide leads to accelerated photolysis, increased field loss of active ingredients, and degradation of synergism of "nanoparticle size-light stability-toxicity" to the level of control 3, verifying the three-level synergism of "nanoparticle size-light stability-toxicity".

[0136] (8) Double component deficiency (Example 15)

[0137] Sensitive strain LC of Example 15 50 = 2.0 mg / L, resistant LC 50 = 20 mg / L, CTC = 100, control effect 50%, close to controls 1 / 2.

[0138] The double deficiency of nanometer titanium dioxide and organosilicon completely invalidates the synergism of "light stability-penetration", and the toxicity degrades to the level of single agent, proving the indivisibility of multi-component synergism.

[0139] (9) Nanometer titanium dioxide particle size (Examples 17-18)

[0140] LC of Example 17 (60 nm) 50 = 0.82 mg / L, CTC = 153; LC of Example 18 (100 nm) 50 = 0.85 mg / L, CTC = 150, both slightly lower than Example 2.

[0141] The light stability efficiency of 30 nm nanometer TiO2 is the best, and 60-100 nm leads to a small decline in toxicity due to slightly accelerated photolysis, but still maintains high efficiency (CTC > 150), verifying the practicability of the particle size range.

[0142] The CTC of prior art control 3 is 130, and the penetration efficiency is 55%; through the synergism of "double targets + double penetration aids" in the present application, the CTC is improved to 156, and the penetration efficiency is improved by 42%, and the LC of the resistant population 50 is reduced by 33% (8 mg / L vs. 12 mg / L).

[0143] The prior art relies on single target + conventional aids, and the present application realizes double synergism of "toxicity-penetration", and the delay effect of resistance is improved by 50%.

[0144] From Table 4 analysis:

[0145] (1) Active ingredient concentration gradient (Examples 1-3)

[0146] Example 1 (15% total content) 14-day control efficiency 70%, duration 12 days; Example 3 (60%) 14-day control efficiency 90%, duration 20 days, 2-3 days longer than Example 2 (88% / 18 days).

[0147] It is shown that high content of active ingredient combined with high dose of nano-TiO2 (0.5%) can extend the duration to 20 days through the dual synergy of "toxicity enhancement + light stability enhancement", proving the positive synergy of concentration and light stability.

[0148] (2) Light stabilizer ratio (Examples 4-5)

[0149] Example 4 (1:1) 14-day control efficiency 85%, duration 16 days; Example 5 (1:2) 14-day control efficiency 82%, duration 15 days, both shorter than Example 2 (88% / 18 days). It is shown that a 1:2 ratio of light stabilizer leads to a decrease in free radical capture efficiency, accelerated loss of active ingredient in the field, and a synchronous reduction in control efficiency and duration, verifying the field criticality of light stabilizer ratio.

[0150] (3) Light stabilizer variety replacement (Examples 6-8)

[0151] Example 6 (662 + chlorobenzotriazole) 14-day control efficiency 87%, duration 17 days; Example 8 (1:2) 14-day control efficiency 85%, duration 16 days, close to Example 2. It is shown that similar light stabilizers have equivalent field control efficiency, and a 1:2 ratio does not exceed the light stabilizer threshold, still meeting field requirements.

[0152] (4) Anti-crystallization agent ratio (Examples 9-10)

[0153] Example 9 (1:1) 14-day control efficiency 88%, duration 18 days, consistent with Example 2; Example 10 (1:2) 14-day control efficiency 88%, duration 18 days. It is shown that the anti-crystallization agent ratio does not affect field control efficiency, and its function is mainly reflected in storage stability, verifying the transmission synergy of "laboratory stability - field efficacy".

[0154] (5) Absence of organosilicon synergist (Example 11)

[0155] Example 11 14-day control efficiency 65%, duration 10 days, equivalent to Control 3, 25% lower than Example 2. It is shown that the absence of organosilicon synergist leads to insufficient spreading of the pesticide on the leaf surface (contact angle > 40°), a decrease in penetration efficiency from 78% to 50%, and a significant decline in field control efficiency, verifying the direct synergy of "penetration - control efficiency".

[0156] (6) Light stabilizer deletion (Example 12)

[0157] Example 12 has 70% control efficiency at 14 days and a persistence of 12 days, which is 18% lower than Example 2 and close to Example 1. This shows that the absence of light stabilizer accelerates the photolysis of the active ingredient in the field, and the effective concentration drops below the lethal threshold after 7 days, and the persistence is shortened to 12 days, verifying the decisive role of "light stability-persistence".

[0158] (7) Anti-crystallization agent deletion (Example 13)

[0159] Example 13 has 88% control efficiency at 14 days and a persistence of 18 days, which is consistent with Example 2, and only the crystallization rate during storage increases. This shows that the anti-crystallization agent does not affect the field efficacy, and its absence does not interfere with the field action of the active ingredient, proving the functional separation of "storage-field".

[0160] (8) Nanometer titanium dioxide deletion (Example 14)

[0161] Example 14 has 55% control efficiency at 14 days and a persistence of 10 days, which is equivalent to Control 3 and 37% lower than Example 2. This shows that the deletion of nanometer titanium dioxide leads to the collapse of photolysis resistance, and the 7-day residual rate of the active ingredient is <50%, the control efficiency is flat with Control 3, verifying the basic role of "nanometer shielding-field persistence".

[0162] (9) Dual component deletion (Example 15)

[0163] Example 15 has 30% control efficiency at 14 days and a persistence of <7 days, which is close to Controls 1 / 2. This shows that the dual deletion of nanometer titanium dioxide and organosilicon completely disables the "light stability-permeation" synergy, and the decay rate of efficacy is consistent with single agents, proving the necessity of multi-component synergy in the field.

[0164] (10) Nanometer titanium dioxide particle size (Examples 17-18)

[0165] Example 17 (60nm) has 87% control efficiency at 14 days and a persistence of 17 days; Example 18 (100nm) has 85% control efficiency at 14 days and a persistence of 16 days, both of which are slightly lower than Example 2. This shows that 30nm nanometer TiO2 has the best light stability efficiency, and 60-100nm has a slightly accelerated photolysis, resulting in a 1-2 day shortening of the persistence, but still significantly better than Control 3, verifying the field applicability of the particle size range.

[0166] The post-treatment 14-day control 1 / 2 (single dose) prevention effects were 25% / 20%, and the persistence period was <7 days / <5 days, due to strong single-target resistance and fast photolysis; the post-treatment 14-day control 3 (CN115553297A) prevention effect was 55%, and the persistence period was 10 days, due to insufficient dispersion stability (particle size 550 nm) of the conventional adjuvant compounding system and a photolysis inhibition rate of only 65%.

[0167] In summary, the core creativity of the present application lies in that, through accurate component design and proportion optimization, four functional modules of dispersion stability, penetration enhancement, photolysis inhibition and crystallization blocking produce a synergistic effect. Each component is deeply coupled through interfacial chemistry, photochemistry and toxicology mechanisms, such as the dispersion agent improving the dispersion uniformity of the light stabilizer, the anti-crystallization agent indirectly reducing the photolysis reaction sites, forming a synergistic effect that cannot be expected by the prior art; compared with the prior art, the present application is excellent in core indicators such as physical stability, photolysis resistance and resistance management, and solves the problems of traditional suspensions such as "photolysis, low-temperature crystallization and strong resistance".

Claims

1. An insecticidal suspension, characterized in that: The invention comprises the following components in percentage by weight: 5-20% of chlorfenapyr, 10-40% of lufenuron, 1-5% of modified rosin polyether modifier, 0.5-10% of sodium polycarboxylate, 0.1-2% of organosilicon synergist, 0.1-1% of light stabilizer, 0.3-1% of anti-crystallization agent, 0.1-0.5% of nano titanium dioxide, and the balance is deionized water.

2. The insecticidal suspension according to claim 1, characterized in that The polycarboxylate sodium salt is SP-2700 or a similar polycarboxylate dispersant, and the suspending agent further comprises 0.1-2% by weight of an organosilicon synergist, which is a polyether-modified trisiloxane or a surfactant with a similar structure.

3. The insecticidal suspension according to claim 2, characterized in that The particle size of the nano titanium dioxide is 30 to 100 nm.

4. The insecticidal suspension according to claim 3, characterized in that The particle size D90 of the suspension is ≤200 nm.

5. The insecticidal suspension according to claim 4, characterized in that The weight ratio of chlorfenapyr to lufenuron is 1:2-5.

6. The insecticidal suspension according to claim 5, characterized in that The light stabilizer is a compound of a hindered amine light stabilizer and a benzotriazole compound, with a weight ratio of 1:0.5-2.

7. The insecticidal suspension according to claim 6, characterized in that The hindered amine light stabilizers include hindered amine 770 and hindered amine 662; the benzotriazole compounds include UV-P and 2-(5-chloro-2H-benzotriazole-2-yl)-4-methyl-6-(tert-butyl)phenol.

8. The insecticidal suspension according to claim 7, characterized in that The anti-crystallization agent is a compound of hydroxypropyl-β-cyclodextrin and polyethylene glycol, with a weight ratio of 1:0.5-2.

9. A method for preparing a suspension according to any one of claims 1 to 5, characterized in that: The nano suspension concentrate was prepared by mixing cypermethrin, lufenuron and nano titanium dioxide, adding modified rosin polyether modified product, polycarboxylic acid sodium salt and deionized water, and dispersing the mixture at a high-speed shearing speed of 10,000 to 20,000 rpm for 20 to 40 minutes, and then homogenizing the mixture 2 to 4 times in a high-pressure homogenizer at a pressure of 100 to 200 MPa to prepare the nano suspension concentrate.

10. Use of the suspension according to any one of claims 1 to 8 in controlling lepidopteran pests.

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