GB969221A - Improvements in or relating to hardenable condensation products - Google Patents

Abstract

Hardenable condensation products are prepared by reacting, in an alkaline medium and in the absence of free phenolic compounds of phenyl glycidyl ether, a chlorine-containing epoxy compound and a substantially anhydrous novolak formed from more than 3 mols of o-cresol with 2 mols formaldehyde and containing fewer than 3 o-cresol nuclei per molecule. Suitable epoxy compounds are epichlorhydrin and glycerol dichlorhydrin. The o-cresol starting material may contain small amounts of phenol, m or p-cresol, or xylenol. The alkali is preferably added to the mixture of novolak and epoxy compound and may be added in stages. Reaction may be in a solvent, which may be an excess of the epoxy compound.ALSO:Hardenable condensation products are prepared by reacting, in an alkaline medium and in the absence of free phenolic compounds of phenyl glycidyl ether, a chlorine-containing epoxy compound and a substantially anhydrous novolak formed from acid condensation of more than 3 mols of o-cresol with 2 mols of formaldehyde, said novolak containing fewer than three o-cresol nuclei per molecule. Suitable epoxy compound are epichlorohydrin and glycerol dichlorohydrin. The o-cresol used for making the novolak may contain small amounts of phenol, m-cresol, p-cresol, or xylenol. The alkali is preferably added to the mixture of novolak and epoxy compound. Reaction may be performed in a solvent, which may be provided as an excess of epoxy compound-afterwards removed by distillation. The products may be hardened with bases, acids, acid anhydrides or Friedel-Crafts catalysts. They may be processed together with phenol-, melamine-, or urea-aldehyde resins or with other epoxy resins and may be used for lacquers, adhesives, casting or moulding.