FIELD: agriculture.
SUBSTANCE: invention relates to block copolymers which form a polyelectrolyte layer adsorbed on a phase interface in a colloidal aqueous solution, which can be used in agrochemical compositions. Agrochemical composition containing particles of at least one agrochemical and a dispersing system containing a block copolymer forming a polyelectrolyte layer, wherein said block copolymer comprises (A) a hydrophobic anchor moiety and (B) at least one hydrophilic charged stabilizing moiety containing at least one charged monomer, where said block copolymer is adsorbed on hydrophobic surfaces of agrochemical particles, and where a) molar ratio of hydrophobic anchor fragment to hydrophilic charged stabilizing fragment is 1:2–4, and wherein (i) the weight of the block copolymer forming the polyelectrolyte layer is from 10,000 to 25,000 g/mol; (ii) the weight of the hydrophilic charged stabilizing moiety ranges from 5,000 to 100,000 g/mol; and/or (iii) hydrophobic anchor moiety contains alkyl acrylate monomers and weight of hydrophobic anchor moiety ranges from 1,500 to 3,500 g/mol; b) the weight ratio of the hydrophobic anchor moiety to the hydrophilic charged stabilizing moiety is less than 0.6, and/or c) at least 60 wt. % of the hydrophilic charged stabilizing moiety are charged monomers. Or, in the agrochemical composition, the block copolymer contains up to 150 monomers, the weight of the block copolymer ranges from 10,000 to 31,000 g/mol, c) the weight of the hydrophilic charged stabilizing fragment is from 5,000 to 100,000 g/mol, d) the weight of the hydrophobic anchor fragment is from 500 to 5,000 g/mol, wherein the hydrophobic anchor moiety contains alkyl acrylate monomers, e) the weight percentage of the stabilizing moiety is 65–90 % of the total weight of the block copolymer, and/or f) the concentration of the block copolymer in composition is 0.2–3 % w/w.
EFFECT: inclusion of a block copolymer in agrochemical compositions provides stabilization of an agricultural preparation in high concentrations against flocculation and coagulation at low concentration of a dispersant and reduces friction between particles, which facilitates the granulation process.
31 cl, 10 tbl, 8 dwg, 7 ex
