GB413345A - Improvements in the manufacture and production of resinous condensation products - Google Patents

Abstract

Resinous condensation products are made by heating polyamides of carboxylic acids containing more than four carbon atoms with formaldehyde substances, which include formaldehyde, its polymers such as tri- or poly-oxymethylene, para- and meta-formaldehyde and substances yielding formaldehyde such as hexamethylenetetramine and acetals. If the reaction is carried out in a weakly alkaline medium, N-methylol compounds of the polyamides are formed, which are further condensed to resinous products. Suitable polyamides are those of open chain and cycloaliphatic, aliphatic-aromatic and aromatic polycarboxylic acids, for example adipic, methyl-adipic, suberic, sebacic, phthalic, hexahydro-o-phthalic, chlorinated phthalic, phenylene di-acetic, naphthalic, citric and diphenic acids; of acids obtained by addition of hydrocyanic acid to unsaturated fatty acids with subsequent saponification of the nitrile group; of acids obtained by oxidation of substances such as waxes, e.g. paraffin wax, oils, fats, fatty acids; distillation residues from the refining of fatty acids, hydrogenated mono- or poly-nuclear aromatic hydrocarbons or their derivatives with the aid of oxygen-containing or -supplying substances, e.g. nitric acid and nitrous gases; of polybasic ether carboxylic acids such as diglycollic or dilactylic acids; of oxidation products of polyalkylene glycols; of sulphur-containing acids such as thiodiglycollic or dithiodiglycollic; or of nitrogen-substituted acids such as imino-a a <1> dipropionic and trimethylamine tricarboxylic acids. The formaldehyde substance may be used in the vapour or solid form or dissolved in water or organic solvents, especially those containing oxygen, e.g. esters such as butyl acetate, dioxane, ketones, methyl, ethyl, propyl, butyl, amyl or benzyl alcohols and ethylene glycol mono-phenyl ether. The reaction is carried out preferably at temperatures of between 120 DEG and 130 DEG C. There may be added organic liquids, especially those containing hydroxyl groups, for example ethyl, butyl or benzyl alcohol, ethylene glycol, glycerol, ethylene glycol monoethyl, monophenyl, or monocresyl ethers, ethylene glycol monoacetate, oleic acid, linoleic acid, china wood oil acid or ricinoleic acid mono- and di-glycerides, castor oil, and hydroxy-ketones. Acid or other usual condensing agents may be used. Substances capable of reacting with formaldehyde, such as urea and its derivatives and amines such as aniline may be added before, during or after the condensation. The products may be hardened by heating to temperatures above those used in the condensation, and hardening accelerators, for example acids or substances capable of splitting off acids, such as ammonium chloride or benzalchloride may be used. The resins may be added to resinous materials to reduce their brittleness and may be used in making lacquers and varnishes, artificial leather, laminated sheets and foils, pressed articles and as impregnating agents for textiles and binding agents for abrasive materials. Specifications 17414/11, [Class 2 (iii)], and 395,340 are referred to.