Patent GB-906322-A (GB)
Title: Improvements in production of composite epoxy resins
Inventor: PRICE HERBERT PETER
IPC: C08G59/04
Filed: 1959-11-13
Abstract: Epoxide resins are made by subjecting mixtures of (1) chlorohydrin ethers of alcohols, (2) polyhydric phenols or partial chlorohydrin ethers of a polyhydric phenol and (3) epichlorohydrin to dehydrohalogenation in the presence of an alkaline dehydrohalogenating agent.  In the absence of an excess of epichlorohydrin, high molecular weight aliphatic-modified epoxy resins are produced.  The chlorohydrin ethers of aliphatic alcohols include monochlorohydrin ethers of monohydric alcohols and mono- or dichlorohydrin ethers of dihydric, trihydric or polyhydric alcohols, which includes dihydroxyalkyl ethers of dihydric phenols.  The polyhydric phenols include resorcinol, hydroquinone and bisphenol. Suitable dehydrohalogenating agents are sodium silicate, aluminate or zincate or caustic alkali in aqueous solution.  Solvents such as dioxane, methyl isobutyl ketone or xylol may be used.  Examples describe the preparation of epoxide resins from bisphenol, epichlorohydrin and (a) the dichlorohydrin ether of 1,4-butanediol, (b) the dichlorohydrin ether of trimethylol propane or (c) the dichlorohydrin ether of polypropylene glycol (1,200 or 400), the dehydrohalogenation being effected by NaOH in water.  The epoxide resins may be cured with amine catalysts such as diethylene triamine or metaphenylene diamine or other curing agents such as urea-formaldehyde resins, melamine formaldehyde resins or toluene diisocyanate.  By using an excess of epichlorohydrin in the above process, monomeric glycidyl polyethers are obtained which also may be cured with the amine catalysts.ALSO:Glycidyl polyethers are made by subjecting mixtures of (1) chlorohydrin ethers of aliphatic alcohols, (2) polyhydric phenols or partial chlorohydrin ethers of a polyhydric phenol and (3) epichlorohydrin to dehydrohalogenation in the presence of an alkaline dehydrohalogenating agent.  The chlorohydrin ethers of aliphatic alcohols include monochlorohydrin ethers of monohydrin alcohols and mono- or dichlorohydrin ethers of dihydric, trihydric or polyhydric alcohols, which include dihydroxyalkyl ethers of dihydric phenols.  Such chlorohydrin ethers are made by reacting the alcohol with epichlorohydrin in the presence of a condensation catalyst, e.g. BF3 ether complex.  The polyhydric phenols include resorcinol, hydroquinone and bisphenol.  When a mixture of a dichlorohydrin ether of a polyhydric alcohol, a dihydric phenol and epichlorohydrin is dehydrohalogenated, the mol proportions of dichlorohydrin ether to epichlorohydrin can vary from 9:1 to 1:9 and the mol proportions of dichlorohydrin ether plus epichlorohydrin to dihydric phenol can vary from 1:1 to not more than 3:1.  The dehydrohalogenation can be effected using excess of epichlorohydrin as a solvent, and the products formed are largely monomeric glycide ethers of the alcohol and phenol.  Suitable dehydrohalogenating agents include aqueous caustic soda, alkali metal complexes and salts such as sodium silicate, sodium aluminate and sodium zincate. Organic solvents such as dioxane, methyl isobutyl ketone and xylol may be used.