GB724099A - Improvements relating to adhesives - Google Patents

Abstract

A homogeneous and stable adhesive composition is made by reacting a polyvalent metal compound with one or more different metal compounds, to form an inorganic precipitate, in an aqueous solution of a cellulose ether carboxylic acid or an organic derivative thereof or a salt of either. When such a salt is used it may be reckoned as one of the aforesaid different metal compounds. Casein may be added. The ingredients may be stirred during the reaction, and they may be heated, particularly during its final phases. The ingredients may be intimately mixed in the dry state, e.g. as powders, and a desired amount of water may then be added. In examples (1) a dry mix is made by mixing the sodium salt of carboxymethylcellulose with either aluminium sulphate and magnesium oxide or with calcium hydroxide; (2) aluminium sulphate and slaked lime are reacted together in the product obtained by etherifying cellulose with monochlorpropionic acid; (3) chalk is added to an aqueous solution of cellulose glycollic acid and sodium sulphate, made by reacting the sodium salt of carboxymethylcellulose with dilute sulphuric acid; urea or melamine may be added; (4) a solution of copper sulphate in ammonia is added to an aqueous solution of the sodium salt of carboxymethylcellulose, and the mixture is heated to drive off ammonia and precipitate a copper compound; aluminium sulphate or hydroxide may be added; (5) iron hydroxide is precipitated from a solution of iron sulphate by adding sodium carbonate in the presence of the crude product obtained by etherifying wood with mono-chloracetic acid, and the resulting mixture is made homogeneous by heating it.ALSO:A homogeneous and stable adhesive composition is made by reacting a polyvalent metal compound with one or more different metal compounds, to form a precipitate, in an aqueous solution of a carbohydrate ether carboxylic acid or an organic derivative thereof or a salt of either (see Group V). In an example, aluminium sulphate and slaked lime are reacted together in the product obtained by etherifying starch with monochloracetic acid.ALSO:A homogeneous and stable adhesive composition is made by reacting a polyvalent metal compound with one or more different metal compounds, to form an inorganic precipitate, in an aqueous solution of a carbohydrate ether carboxylic acid or an organic derivative thereof or a salt of either. When such a salt is used, it may be reckoned as one of the aforesaid different metal compounds. Casein may be added. The ingredients may be stirred during the reaction. They may be heated, particularly during its final phases. The components may be intimately mixed in the dry state, e.g. as powders, and a desired amount of water may then be added. In examples: (1) The sodium salt of carboxymethylcellulose is mixed either with aluminium sulphate and magnesium oxide or with calcium hydroxide to form a dry mix; (2) aluminium sulphate and slaked lime are reacted together either in the product obtained by etherifying cellulose with mono-chlorpropionic acid or in the product obtained by etherifying starch with mono-chloracetic acid; (3) chalk is added to an aqueous solution of cellulose glycollic acid and sodium sulphate, obtained by reacting the sodium salt of carboxymethylcellulose with dilute sulphuric acid; urea or melamine may be added; (4) a solution of copper sulphate in ammonia is added to an aqueous solution of the sodium salt of carboxymethylcellulose and the mixture is heated to drive off ammonia and precipitate a copper compound; aluminium sulphate or hydroxide may be added; (5) iron hydroxide is precipitated from a solution of iron sulphate by adding sodium carbonate in the presence of the crude product obtained by etherifying wood with mono-chloracetic acid and the resulting mixture is heated until it becomes homogeneous.