Abstract:

Using formaldehyde and melamine as wall materials, encapsulated emamectin benzoate-toluene microcapsules were prepared via an in-situ polymerization process. The experimental results show that well defined microcapsules with uniform particle size around 4.4 μm could be formed when the mass ratio of melamine to formaldehyde is 1∶2, core to wall is 3 to 2, using 1% mass fraction of HEC as emulsifying agent, the stirring ratio is 1000 r/min, pH value is 5.0, the temperature and heating time are 50 ℃ and 2 h, respectively. An improved photodegradation of emamectin benzoate microcapsules toward UV light could be achieved. Fourier-transform infrared spectroscopy(FT-IR) results also demonstrate the successful encapsulation of emamectin benzoate within the wall material.

Key words: emamectin benzoate, microcapsules, in-situ polymerization, preparation conditions, characterization