A method of dispersing an insoluble material in an aqueous solution comprising the following steps: (i) providing a formulation comprising at least one insoluble material and at least one dispersant comprising a water soluble agriculturally acceptable derivative of an alternating copolymer or an agriculturally acceptable salt thereof wherein said alternating copolymer comprises at least one residue of a first comonomer and at least one residue of a second comonomer, wherein said first comonomer comprises alpha,beta-unsaturated oxyacids or anhydrides and said second comonomer comprises olefinic compounds containing one or more polymerizable double bonds； and (ii) dispersing said formulation in an aqueous medium.
