| 摘要 |
A process for the preparation of solid polyglycidyl ethers of polyhydric alcohols, which ethers have a Durrans melting point of at least 50 DEG C., by reacting not more than 1.75 mol of an epihalohydrin or a glycerin halohydrin with one mol of a polyhydric phenol is characterized in that an aqueous alkali hydroxide solution is added to a mixture of the halohydrin, the polyhydric phenol and water. The preparation may be carried out in an oxygen-free or substantially oxygen-free atmosphere (e.g. nitrogen) and/or in the presence of sodium dithionite. The alkali hydroxide specified is sodium hydroxide and the halohydrin is epichlorohydrin. Many polyhydric phenols are specified including monomeric polyhydric phenols; novolac resins from the reaction of phenols with, for example, formaldehyde, acetaldehyde and crotonaldehyde; and the condensates of phenols with cardanol, aliphatic diols or unsaturated fatty oils. For the purposes of comparison a polyglycidyl ether is prepared by adding epichlorohydrin to a solution of diphenylalpropane in aqueous sodium hydroxide. The products of the invention are useful in the preparation of light-coloured coating compositions. |
