Patent GB-700822-A (GB)
Title: Improvements in or relating to a process of producing a condensation product having fire-resistant properties and to products incorporating said composition
IPC: D06M13/292
Filed: 1951-06-13
Abstract: A water - soluble nitrogen and phosphorus containing condensation product substantially free from chlorine obtained by reacting phosphorus oxychloride with an ammonia (see Group III) having a molecular weight 180-300 and a nitrogen-phosphorus atomic ratio of 2.1 - 2.3, yielding a solution having an alkaline pH 7.0 - 8.5, and being reactive with cellulose, may be used as a constituent of phenolic resins or aminoplasts, e.g. urea- or melamine-form-aldehyde, or urea-or-melamine-furfural resins, which in the case of aminoplasts, intumesce when heated, and may be used to impregnate fabrics, or may be applied, in combination with phenolic resins to a mass of glass fibres to bond them together and form a material suitable for insulating layers or air filters. Examples describe how (iv) cotton sheeting is impregnated with an aqueous solution containing 30 per cent. of the condensation product and 1.5 per cent. of a water soluble urea-formaldehyde condensation product and is cured at 140 DEG C. for 30 mins; (v) cloth is impregnated with a water solution of a resorcinol-formaldehyde resin (75 parts) containing the condensation product (5 parts) and a basic condensation catalyst (20 parts) and is cured at 150 DEG C.ALSO:A water-soluble nitrogen and phosphorus-containing condensation product, substantially free from chlorine, having a molecular weight 180-300, and a nitrogen-phosphorus atomic ratio of 2.1-2.3, and yielding a solution having an alkaline pH 7.0-8.5 is prepared by reacting phosphorus oxychloride with ammonia at a temperature below 100 DEG C. and then heating the product so formed to at least 110 DEG C., but below 150 DEG C.  The reaction may be carried out with at least the stoichiometric proportion of gaseous or liquid ammonia in an inert solvent, e.g. kerosene, naphtha, hexane, benzene, or acetone, in an autoclave to form an intermediate product soluble in anhydrous liquid ammonia.  The further heating for 30 minutes to 6 hours in the autoclave converts the nitrogen-phosphorus-containing intermediate product to a form insoluble in anhydrous liquid ammonia. After filtration, the inert solvent may be recovered by distillation, and resulting product may be separated from the ammonium chloride also formed by (i) treatment with water to dissolve the product, which is precipitated from the solution by methanol, (ii) treatment with anhydrous liquid ammonia to dissolve the ammonium chloride, or (iii) treatment with methanol to dissolve the ammonium chloride. The nitrogen-phosphorus-containing condensation product may be used to treat cellulose materials to form a cation exchange material, which after acid treatment, yields silica sols when contacted with sodium silicate solution.  The condensation products may also be used to render combustible materials, such as wood, paper or cotton fabric glowproof, and as constituents of aminoplast or phenolic resins.ALSO:A water-soluble nitrogen- and phosphorus-containing condensation product substantially free from chlorine obtained by reacting phosphorus oxychloride with ammonia (see Group III), having a molecular weight 180-300 and a nitrogen-phosphorus atomic ratio of 2.1-2.3, yielding a solution having an alkaline pH 7.0-8.5, and being reactive with cellulose, may be used to treat cellulose materials to form after heating to 100-200 DEG  C. and preferably after acid treatment, a cation exchange material. Examples describe how cotton fabric is impregnated with the condensation product, is soaked with a 5 per cent soluton of hydrochloric acid and is used as hydrogen ion exchange material for calcium chloride solution, the resulting acid being titrated against caustic soda to determine the cation exchange capacity.