Process for producing multiple types of microcapsules
申请人:STAUFFER CHEMICAL COMPANY
公开号:EP0148769A1
公开(公告)日:1985-07-17
A process of encapsulating water-immiscible material within discrete capsules of polyurea without addition of a second reactant, whereby hydrolysis of an isocyanate mo- nomertoform an amine takes place, which in turn reacts with another isocyanate monomer to form polyurea, which comprises the steps of
(a) providing at room temperature, a dispersion of
(i) a plurality of water-immiscible phases, each phase comprising the water-immiscible material to be encapsulated and at least one organic polyisocyanate in
(ii) an aqueous phase comprising a solution of water, a surfactant and a protective colloid; and
(b) heating and maintaining said dispersion in a temperature range of about 40° C to about 90° C, whereupon said water-immisicible material is encapsulated within discrete polyurea capsuler enclosures directly usable without further separation or purification.
A pesticidal formulation having a rapid efficacy and residual activity, comprising a mixture of a part of a poorly water-soluble pesticide encapsulated in water-insoluble polymer coatings with the remaining part of said pesticide emulsified or suspended in water.
Pest control compositions and methods for forming a pest control composition, comprising the steps of providing a lower polymer weave; providing an upper polymer film; and mixing a pest control agent with a polymer and extruding the resulting mixture between the lower polymer weave and the upper polymer film are discussed. In addition, methods of forming a pest control composition comprising providing a lower polymer weave layer and mixing a pest control agent with a polymer and extruding the resulting mixture on the lower polymer weave layer and pest control compositions formed by such processes are discussed. Also described are pellets and monolayer films of pest control agent and polymer.