Studies on cloud point of agrochemical microemulsions

As part of our studies on green agrochemical formulations, four o/w agroche mical microemulsions have been prepared using five non-ionic surfactants wi th various hydrophilities and one co-surfactant. The effects of various for mulation conditions, including surfactants, surfactant concentration, mixtu re of surfactant with various concentrations, pesticides in oil phase and w ater quality in the continuous medium on the cloud points of microemulsions have been investigated. The results showed that the values of the cloud po int of microemulsions were depended on the nature of agrochemical, the surf actants used and the concentration of surfactants. Surfactants with higher HLB value at same concentration produce more stable agrochemical microemuls ions, i.e. with higher cloud point. The results showed that the match betwe en surfactant and oil phase or pesticide oil phase was the key to formulate stable microemulsions, However, the water quality was showed almost no eff ect on the cloud point of the agrochemical microemulsions in the studies. ( C) 2000 Elsevier Science B.V. All rights reserved.