GB766772A - An agglutinant and process for sticking together materials - Google Patents

Abstract

Adhesives for sticking materials of all kinds consist of a mixture of the epoxyalkyl ester of a polycarboxylic acid with an alkaline substance. The epoxy-containing esters may be prepared by reacting epichlorhydrin with alkali metal salts of polycarboxylic acids at raised temperatures and pressure or in the case of aromatic polycarboxylic acids by the action of the acid halide on glycide in the presence of an organic tertiary base. These processes are claimed in Specifications 735,001 and 766,771. A long list of polycarboxylic acids is given, and it is also stated that oleeylalcohol-9,10-epoxide may replace glycide in the preparation of the esters. The polycarboxylic acid may also be a high molecular weight carboxyl-terminated polyester. Suitable alkalies as hardening agents are piperidine, ethylenediamine, diethylenetriamine, triethylenetetramine, dicyandiamidine, diacetoneamine, benzidine, caprolactam, a condensate of dicyandiamide and diethylenetetramine, sodium or calcium hydroxide or quick lime. The preferred proportion of alkali is 5-20 per cent. Plasticizers, e.g. dibutyl phthalate or tricresylphosphate may be included in the adhesive compositions. The compositions may also include other epoxy compounds, e.g. glycidyl ethers of polyvalent phenols or mono-epoxy compounds, e.g. phenyl-glycidyl ether, glycidyl esters of fatty acids, or p-toluenesulphonic acid glycidyl ester. The esters may be used in solution in volatile solvents, e.g. esters or ketones. Other possible additives are wood dust, fibres or chips, stone dust, mica, animal glue, starch derivatives or melamine resins. The setting time may be reduced by heating. The adhesives may also be used as binders for moulded articles or for laminated material. A number of examples are given illustrating the use of various additives as mentioned above, together with resin intermediates prepared from dipotassium phthalate, dipotassium adipate or dipotassium maleate, and epichlorhydrin, or from terephthalic acid dichloride and glycide in presence of triethylamine.