METHOD OF PRODUCING CURING AGENT Russian patent published in 2011 - IPC B01J31/06 C08G59/40 

FIELD: chemistry.

SUBSTANCE: invention relates to curing agents used in epoxide composite materials for acid curing. Disclosed is a method of producing a curing agent by reacting epoxide compounds with anhydrous orthophosphoric acid in molar ratio 3:1-9:1 mole of epoxide groups per mole of acid, in which a reactive solvent is added to both the epoxide compound and acid, where he said solvent is selected from ketones, dimethyl formamide or dimethyl sulphoxide, in amount of 0.2-0.5 pts.wt per 1 pts.wt of reagents. The acid solution is then heated to temperature 50-70°C and the epoxide compound is proportionally added. The orthophosphoric acid used is obtained by reacting aqueous sulphuric acid solution with phosphorus pentoxide, and the epoxide compounds used are selected from phenylglycidal or butylglycidal ether, epichlorohydrin, diane epoxide oligomers or mixtures thereof with aliphatic epoxide oligomers.

EFFECT: method enables to obtain a curing agent which increases the degree of cure and improves physical and mechanical properties of coatings, while preserving their processing properties (working life and stability) regardless of storage time before application onto an article.

1 cl, 2 tbl, 15 ex