Patent GB-877827-A (GB)
Title: Improvements in the curing of epoxide resins
IPC: C08G59/50
Filed: 1957-09-16
Abstract: A polyepoxide having a 1- 2-epoxy equivalency greater than one is cured with 0,5-1,5 equivalents per epoxy group of a halohydrin etheramine condensate prepared by reacting 0,55-1 mol of ammonia or an amine having at least two amino hydrogen atoms per halogen atom of a halohydrin ether of an alcohol and neutralizing the resulting hydrohalide salt.  When the halohydrin ether contains more than two halogen atoms, one mol of the nitrogen compound is used for each halogen atom.  In examples, curing agents are prepared: (1) from the dichlorhydrin ether of 1, 5-pentanediol and tetraethylene pentamine and neutralization of the hydrochloride with caustic soda; (2) from 0,5 mol of a trichlorhydrin ether of a trimethylol propane, 1,5 mols of diethylene triamine and 1,5 mols of caustic soda; (3), (4) from a dichlorhydrin ether of a polyethylene glycol, hexamethylene diamine and caustic soda; (5) from one mol of a dichlorhydrin ether of 1, 5-pentanediol, 1,25 mols of m-xylylene diamine and 2 mols of sodium hydroxide.  It is also stated that halohydrin ethers of monohydric alcohols, e.g. propanol, butanol, hexanol or lauryl alcohol may be condensed with amines.  Particularly useful curing agents may be employed from halohydrin ethers of polyethylene glycols having molecular weights of several hundred or even of two thousand.  The epoxide resin may be cured in presence of monoepoxides, e.g. butyl glycidyl ether or of polysulphide resins containing terminal H groups.  In examples of curing epoxide resins:-(6) a film is formed from a solution in xylene butanol and 2-ethoxy ethanol of an epoxide resin from bisphenol A and epichlorhydrin and of a butylated urea-formaldehyde resin and of the condensate of Example (1).  It is cured by baking; (7) is similar using the curing agent of Example (2), and Example (8) uses the curing agent of Example (3). In Example (9) the curing agent of Example (4) is used; (10) a mixture of an epoxide resin 'A' with a product obtained by modifying that resin with butyl glycidyl ether is cured with a neutralized condensate from the monochlorhydrin ether of lauryl alcohol and diethylene triamine; (11) is similar to (10) using a curing agent from the monochlorhydrin ether of n-butyl alcohol, tetraethylene pentamine and caustic soda. In Example (12) Resin 'A' was cured with an agent from a dichlorhydrin ether of polyethylene glycol, diethylene triamine, metaphenylene diamine and caustic soda.  Tables are given of the physical properties obtained by curing epoxide resins with various curing agents according to the invention alone or in combination with conventional amine curing agents.  The cured products are particularly flexible.  The cured products are useful as films, laminates, cast or moulded articles.  Specification 679,536 and U.S.A.  Specifications 2,467,171, 2,538,072, 2,581,464, 2,615,007, 2,615,008 and 2,698,315 are referred to.ALSO:Curing agents for epoxide resins are neutralised condensates of 0.55-1 mol of ammonia or an amine having at least two amino hydrogen atoms with a halohydrin ether of a mono- or poly-alcohol.  In Examples (1), one mol of the di-(chlorhydrin) ether of 1,5-pentanediol (formed from the diol and epichlorhydrin) is reacted with two mols of tetraethylene pentamino and 2 mols of caustic soda.  Water is removed after reaction by azeotropic distillation with toluene, sodium chloride removed by filtration, and the condensate (M.P. 17 DEG C.; 21.9% N) recovered by distilling off toluene.  (2) The tri(chlorhydrin) ether of trimethylol propane is condensed with diethylene triamine and caustic soda. (3) The di-(chlorhydrin) ether of a polyethylene glycol (M.W. 400) is condensed with hexamethylene diamine and the resulting hydrochloride converted to free base with caustic soda.  (4) is similar to (3) using a polyethylene glycol with M.W. of 600.