Insecticide formulations

A method of forming an insecticide formulation, comprising:

• combining an aqueous phase and an oil phase comprising an isocyanate monomer and at least one insecticide;
• emulsifying the oil phase and the aqueous phase to form a mixture;
• adding a cross-linking ethylenediamine to the mixture, the mixture comprising a molar ratio of ethylenediamine to isocyanate groups of between 0.3 to 1 and 0.8 to 1;
• and
• reacting the isocyanate monomer with the cross-linking ethylenediamine to form the insecticide formulation.

A method of forming an insecticide formulation, comprising:

• forming an oil phase consisting of an aromatic isocyanate monomer, at least one insecticide composition, at least one solvent, and at least one preservative;
• combining the oil phase with an aqueous phase to form a mixture;
• and
• combining ethylenediamine with the mixture to form the insecticide formulation, wherein a molar ratio of the ethylenediamine:aromatic isocyanate monomer is between 0.3 to 1 and 0.8 to 1.

A method for controlling an insect population, comprising:

• forming an insecticide formulation, comprising:
• combining an aqueous phase and an oil phase comprising a hydrophobic isocyanate monomer and at least one insecticide to form a mixture;
• adding a cross-linking ethylenediamine to the mixture, forming a reaction mixture comprising a molar ratio of ethylenediamine to isocyanate groups of between 0.3:1 and 0.8:1;
• and
• reacting the hydrophobic isocyanate monomer with the cross-linking ethylenediamine to form the insecticide formulation;
• and
• applying the insecticide formulation to an area containing or adjacent to a population of insects.

A stable aqueous insecticide formulation comprising:

• a) a microcapsule, having a water insoluble polyurea shell wall prepared by an interfacial polycondensation reaction between a water soluble cross-linking ethylenediamine and an oil soluble isocyanate monomer in which
• (i) the molar ratio of ethylenediamine to isocyanate groups is between 0.3 to 1 and 0.8 to 1,
• (ii) the polyurea shell has a thickness of greater than about 2 nanometers (nm) and less than about 50 nm,
• (iii) the average particle size is from 1 micrometer (μm) to 30 μm, and
• (iv) containing an inner liquid core comprised of an insecticide at least partially encapsulated by the polymer shell;
• and
• b) a continuous aqueous phase.