GB720035A - Improvements in the production of hardenable resins - Google Patents

Abstract

Hardenable resins are prepared by condensing an aldehyde with a condensation product prepared from 40-200 parts of a phenol with 100 parts of an oxygen-containing reaction product of an aromatic hydrocarbon and an aldehyde. The aromatic hydrocarbon may be alkylated, e.g. xylene or polynuclear non-alkylated as in Specification 720,034. Preferably 50-200 parts of 30 per cent formaldehyde or an equivalent amount of a formaldehyde polymer or of a substance generating formaldehyde, e.g. hexamethylene-tetramine, are used per 100 parts of condensation product. Substances which can react with aldehydes to form resins, e.g. acid amides, phenols, amines, urethanes or ketones may be added to the condensation products prior to their further reaction with aldehyde. Fillers, dyestuffs or pigments, e.g. graphite or carbon black, may be added to the products during their working up. Small amounts of high molecular weight chlorinated aliphatic hydrocarbons may also be incorporated. The products are soluble in ethanol or toluene-alcohol mixtures. In the examples (1) a naphthalene formaldehyde resin is condensed with phenol and the product reacted with formaldehyde in presence of ammonia; (2) is similar, but the reaction with formaldehyde is performed under acid conditions; (3) a xylene-formaldehyde-phenol condensate is reacted with formaldehyde under acid conditions. In example (4) a naphthalene-formaldehyde-phenol condensate is worked up to a pressing mass with a novolac, wood meal, hexamethylene tetramine, magnesium oxide and bleached montan wax. In example (5) a product prepared as in example (2) is mixed with graphite, hexamethylene tetramine and highly chlorinated paraffin on mixing rollers and moulded at 170 DEG C. and 150 kgm/cm.2.