Effect Of Different Factors On The Physical And Chemical Stability Of Pesticides Microemulsion

The prominent problem in the fluid formulation-emulsion is the great use of organic solvents that caused the pollution of environmentThe new formulation-microemulsion which contains less organic solvents and more water as the media has attracted people 'great intrest.However,because of the study of microemulsion is later, at present,pesticide microemulsion still has the problem of the phase separation.The effect of several factors such as surfactant,co-surfactant,water,pH on the chemical and physical stability of microemulsion was studied and the different kind of pesticide microemulsion was compared.The results show that as far as the different kind of pesticides is concerned,the value of HLB of surfactants plays important role in the formulation of microemulsion.To a given system,with the increase of the content of surfactant,the chemical and physical stability of microemulsion is also improved.The co-surfactant can improve the flubility of microemulsion system,but the cloud point of microemulsion will decrease if the content of co-surfactant exceeds a certain scope and it will affect the physical stability of the microemulsion system.Water should be suitable with the hydrophilic lipophilic balance value of surfactant,microemulsion system can form when the hardity of water is less 342mg/kg.In a word,the factors that affect the HLB value of surfactant will to great extent affect the cloud point of microemulsion and give different effect on the physical property of microemulsion.De-water method was proved to be a creative method in removing water in order to eliminate theainterference to the chromatography and gives a good result.