Thiocarbamate preparation utilizing quaternary ammonium salt catalysts
申请人:STAUFFER CHEMICAL COMPANY
公开号:EP0004377A1
公开(公告)日:1979-10-03
Thiocarbamates are prepared by a process comprising reacting an aqueous solution of a thiocarbamate salt with an organic halide in the presence of a catalytic amount of a quaternary ammonium salt having the formula
in which R4 and R5 are independently selected from the group consisting of C1-C25 alkyl and C2-C25 alkenyl, R6 and R7 are independently selected from the group consisting of C6-C25 alkyl and C6-C25 alkenyl, and Y- is an anion selected from the group consisting of chloride and bromide; and separating the thiocarbamate from the aqueous solution.
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.