Patent GB-849036-A (GB)
Title: Improvements in or relating to a process for preparing glycidyl ethers of phenols
IPC: H01J25/00
Filed: 1958-10-02
Abstract: A glycidyl polyether of a polyhydric phenol is prepared in a continuous manner by continuously introducing as a feed mixture epichlorohydrin or glycerol dichlorohydrin, a polyhydric phenol, an aliphatic ketone containing no more than 4 carbon atoms and water into an elongated reactor where as an intimate mixture the components are heated in the presence of an alkali metal hydroxide at a temperature above about 70 DEG C., continuously withdrawing the reaction mixture to a phase separator, separating the organic phase and recovering the glycidyl polyether therefrom. Suitable polyhydric phenols are a long list of dihydric phenols including halo-phenols, phenol alcohols, phenol ketones, 3-hydroxy phenyl salicylate, and 4-salicoylaminophenol; phloroglucinol, novolac resins obtainable by acid catalyst condensation of phenol, p-cresol or other substituted phenols with aldehydes such as formaldehyde, acetaldehyde and crotonaldehyde; condensates of phenols with cardanol, aliphatic diols, or unsaturated fatty oils.  The preferred ketones are acetone and methyl ethyl ketone, used in amounts of 25 to 50% by weight of the reaction mixture. The alkali metal hydroxide is preferably added as a 5 to 45% aqueous solution and may be added at several points along the reactor or all at the input end.  Glycidyl polyethers prepared from 2,2-bis (4 hydroxyphenyl) propane and epichlorohydrin by processes similar to the above (see also Group IV(b) are used in examples to form dehydrated castor oil fatty acid esters which are used in melamine formaldehyde white baking enamels.  The glycidyl polyether of 2,2-bis (4-hydroxyphenyl) propane is also cured with metaphenylene diamine, or with an adduct of metaphenylene diamine and phenyl glycidyl ether, to form a tough casting.  Specification 401,237 is referred to.ALSO:A glycidyl ether of a phenol is prepared by continuously introducing as a feed mixture, epichlorohydrin or glycerol dichlorohydrin, a phenol, an aliphatic ketone containing no more than 4 carbon atoms, and water into an elongated reactor where as an intimate mixture the components are heated in the presence of an alkali metal hydroxide at a temperature above about 70 DEG  C., continuously withdrawing the reaction mixture to a phase separator, separating the organic phase and recovering the glycidyl ether therefrom.  Any phenol may be used but polyhydric phenols especially dihydric phenols are preferred.  The glycidyl polyethers of polyhydric phenols are solid when the mol ratio of chlorohydrin to phenol is from 1,05 : 1 to 2 : 1, and liquid when the mol ratio is from 5 : 1 to 20 : 1.  The amount of ketone (e.g., acetone or methyl ethyl ketone) used is preferably 25 to 50% by weight of the reaction mixture and the amount of water is at least 2,5%, preferably at least 18% of the mixture.  The alkali metal hydroxide is preferably added as a 5 to 45% aqueous solution and may be added at several points along the reactor when making liquid glycidyl ethers or all at the input end of the reactor when making solid glycidyl ethers.  The temperature used may vary from 70 DEG  C. to 200 DEG  C. and the residence time from 1 minute to 20 minutes.  The mixture recovered from the reactor is allowed to separate into an aqueous phase and an organic phase and the glycidyl ether is recovered from the latter, preferably by distilling under vacuum and recovering the ether as bottoms product.  Specification 401,237 is referred to.