Application of wetting agent:
When the pesticide is hydrophobic solid powder, its surface is not easy to be wet, insoluble in water and sink. Add a wetting agent, due to the wetting molecules on the surface of the solid orientational, can reduce the surface of the water, making water wetting the solid, solid powder dispersed in the water become stable suspensions. For example, the plant leaves and insects have waxy on the surface of the plant, and the liquid is sprayed on the surface of the plant because it can not be moistened to form a ball rolling or evaporating. To make the liquid. In order to make the liquid have good wettability, it can be spread on plant leaves and insect surface to make full effect, often need to add wetting agent to pesticide. The wetting effect is more practical in chemical experiments. After the experiment, the glass instrument must be cleaned. Clean glass instrument wall should not hang water bead and spread a thin and even water film. If the glass is hung with water, the oil is not clean and must be rewashed.
Selection of wetting agent:
In general, the use of ethanol, propylene glycol, glycerin and other substances which are not very strong in hydrophobic substances can be used for wet purposes. In the case of hydrophobic drugs or drugs, the surface active agent between 6 and 15 is usually selected. You can choose from any of the following indicators:
Contact Angle: it is the Angle between the droplets and the surface of the paving. The wetting agent should reduce the contact Angle of the hydrophobic drug At 0, it's completely wet; When the contact Angle of 0 ~ 90 ° can wetting, for hydrophilic drugs; Contact Angle is less than 180 ° for greater than 90 ° when not wetting; When the contact Angle is 180 ° is completely not wetting, for hydrophobic drugs.
The interfacial tension
Contact Angle (interfacial tension) : some wetting agents change the interfacial tension of hydrophobic drugs and solvents.
Quantity of wetting
Wetting point: wetting point refers to the amount of solvent needed to wetting the water of 100g hydrophobic drugs. Adding wetting agent can reduce wet point and reduce the amount of solvent.
Shaoxing Shangyu Simo Research institute of organic Chemistry
Address: Room 1202, Jincheng Building, Shangyu City, Zhejiang Province, China