GB601101A - Improvements in or relating to synthetic resins - Google Patents

Abstract

Combustible synthetic resins are produced by condensation of a compound of formula RCX2NO2 (where R is H, alkyl, alkylol or aryl, and X is H or CH2OH with an aliphatic aldehyde in neutral, acid or alkaline medium at a temperature between room temperature and 150 DEG C. Suitable compounds are nitro-paraffins, e.g. nitromethane, nitroethane or 1-nitropropane; phenylnitromethane, or nitro alcohols containing secondary or tertiary nitro groups such as b -nitro-ethanol; b -nitro-propanol; di-methylol nitro-ethane; di-methylol nitro-propane. Mixtures of compounds may be used. Formaldehyde is the preferred aldehyde. Strong or weak alkalies, basic salts and/or nitrogen bases or salts of nitrogen bases may be used to adjust the reaction medium to the desired pH. Nitrogenous bases are said to take part in the formation of the resin. The reaction may be performed in aqueous or non-aqueous solvents or the reactants may be emulsified. In example I a resin is prepared from formaldehyde, ammonia and 1-nitropropane, the reaction medium becoming neutral or even slightly acidic as the ammonia is taken up by the resin. Example II is similar but has an alkaline reaction medium due to a greater proportion of ammonia. Example III is similar, oily products formed as a result of the initial stages of the reaction being removed before completion of resinification. In example IV hexamethylenetetramine is present to produce an alkaline medium. In example V an ammonium salt and some free acid is present to yield an acid reaction medium. In example VI sodium bicarbonate is used to make the medium alkaline. Example VII is similar to example I but performs the reaction in water-xylene emulsion. In example VIII the reaction medium is alkaline and alcoholic. In example IX, dimethylol nitropropane, formaldehyde and ammonia are condensed together. Example X uses dimethylol nitroethane, example XI b -nitrobutanol and example XII a mixture of b -nitrobutanol and dimethylolpropane. In example XIII dimethylol nitropropane is employed and in example XIV a mixture of dimethylol nitropropane and monomethylol nitropropane. The resins are soluble in liquid aromatic nitrocompounds, e.g. nitrobenzenes, nitrotoluenes, nitroxylenes and nitrophenols and in liquid nitric acid esters, e.g. nitroglycol nitroglycerine and molten pentaerythritol tetranitrate. They may be used as ingredients of high explosives, propellants or pyrotechnic mixtures.