GB924561A - Improvements in or relating to herbicidal compositions containing polychlorophenylacetic acids and salts thereof - Google Patents

Abstract

2,3,6-, or 2,3,5-trichlorophenylacetic acid or 2,3,5,6-tetrachloro-phenylacetic acid or mixtures thereof are prepared by treating benzyl chloride or toluene with chlorine to form the appropriate polychlorinated benzyl chloride, reacting the latter with sodium cyanide to form the corresponding chlorinated phenyl acetonitrile and hydrolysing the latter to the polychlorinated phenylacetic acid.ALSO:A herbicidal composition comprises a mixture containing at least 50% 2,3,6 trichloro phenyl acetic acid or a salt thereof together with 2,35-trichlorophenyl acetic acid or a salt thereof or 2,3,5,6-tetrachlorophenyl acetic acid or a salt thereof and a herbicidal adjuvant. Specified salts are the alkali metal such as sodium or potassium salts, the ammonium, or substituted ammonium salts such as the dimethylamine, trimethylamine ethylene diamine, hydroxyethylethylenediame, diethylene triamine, propylene diamine or triethanolamine salts. Solid formulations may be in the form of powder concentrates containing 5 to 95% of the active ingredients and a conditioning agent such as attapulgite, china clays, diatomaceous earth, walnut shell flour, redwood flour, synthetic fine silica or calcium silicate. The powders may be diluted to form dusts with talc, pyrophyllite tobacco dust or volcanic ash or suspended in liquids to form sprays. The particle size of the solid formulations should be less than 50 m . Liquid suspensions or solutions are prepared in diluents such as water, kerosene, Stoddard solvent, xylene, alcohols, alkylated naphthalenes, glycols, ketones e.g. di-isobutyl ketone or cyclohexanone, diesel oil, or other aromatic herbicidal oils and contain preferably 0.5 to 50% of the active ingredients. Compositions in the form of wettable powders or liquid suspensions may be prepared containing one or more surface active agents e.g. sodium oleate, sulphonated petroleum oils alkyl aryl sulphonates e.g. the sodium salt of an alkyl naphthalene sulphonic acid, polyosyethylene ester of mixed fatty and resin acids concretion with urea, sodium lignin sulphonate or an alkyl aryl polyether alcohol. Other additives include methyl cellulose.