METHOD OF PREPARING COLD-HARDENING EPOXIDE RESIN HARDENERS Russian patent published in 2003 - IPC

FIELD: polymer materials. SUBSTANCE: cold-hardening epoxide resin hardeners useful in epoxide compounds intended for anticorrosive protection are prepared by mixing aromatic and aliphatic di- and polyamines with salicylic acid additive. Preliminarily, aromatic di- or polyamine is brought into reaction with salicylic acid dissolved in product of esterification of o-phthalic acid with hydroxyl- containing compound selected from group including butyl, isononyl, and benzyl alcohols by stirring components in reactor at 50-90 C for 6 to 40 min at ratio aromatic di- or polyamine/salicylic acid/hydroxyl-containing compound between 98:1:1 and 10:20:70. In another reactor, aliphatic di- or polyamine is brought into reaction with the same components by stirring mixture at 30-55 C for 3 to 25 min at ratio aliphatic di- or polyamine/salicylic acid/hydroxyl-containing compound between 96:2:2 and 4:16:80. Preliminarily prepared products based on aromatic and aliphatic amines are then combined and stirred at 15-60 C for 3 to 20 min at ratio from 95:5 to 5:95. EFFECT: enabled preparation of hardeners stable upon long storage and suitable for manufacturing high-strength polymers with elevated heat resistance. 3 tbl