What are the main factors affecting the application of pesticide auxiliaries

Surfactants are composed of hydrophilic and hydrophobic parts. the ability to reduce surface tension depends on the hydrophilic and hydrophobic correlation and the distribution of molecules in different phases (droplets and plant or animal surfaces). The wet spreading performance of the agent on the target and the retention on the target surface directly affect the penetration and biological activity of the target surface, so the addition of surfactant can enhance the distribution of drug molecules on the leaf surface or insect body. so as to promote the absorption of the drug. The effect is also related to the temperature, concentration and atmospheric pressure of the solution.

Effects of structure, polarity and concentration of Surfactants on absorption

Syuan Tan et al found that polyoxyethylene glycol (PEG) series of surfactants can greatly improve the penetration of some spray pesticides on paraxial apple leaf epidermis, but the effect on adsorption is not obvious. It was also pointed out that the hydrophilic and lipophilic balance value (HLB) of PEG surfactants was negatively correlated with the adsorption of surfactants by leaf epidermis and the osmotic effect of 24Mel D. The addition of surfactant can improve the permeability of 24MuthD to stratum corneum membrane, and the permeability decreases with the increase of HLB value of surfactant. Therefore, the change of hydrophilic lipophilic balance value (HLB) of surfactant is an important factor for the change of permeability of 24MuthD.

Penetration of solute in compounds

In the process of evaporation, the amount of matter (composition) permeating into the epidermis has nothing to do with the total amount of solution. The absorption of solute is related to the coefficient and concentration between epidermis and residues, and the permeation rate depends on the affinity between solute and surfactant. The permeation rate of the compound is related not only to the solubility of wax in the epidermis, but also to the evaporation rate of the solvent. After evaporation, the permeation rate of the compound will be affected by the concentration in the horny wax layer and epidermis. Surfactants may have the effect of dredging transport obstacles, hinder the dispersion of compounds, transfer their absorbed sites, change the properties of compounds, reduce their resistance, and create conditions for plants to inhale active compounds. The improvement of osmotic performance, according to the physical and chemical interaction (joint dissolution or infiltration mechanism) between the active components of the drug and the surfactant into the leaves, or the change of transport obstacles in plants induced by special surfactants, thus making it easier for them to carry out particle infiltration.