Patent GB-413624-A (GB)
Title: Manufacture of highly viscous products
IPC: D06M13/51
Filed: 1932-10-12
Abstract: Highly viscous products are manufactured by adding a boron compound, e.g. boric acid or salts thereof, boric anhydride, organic boron compounds such as boric acid esters, fluoboric acid or borofluoroacetic acid, to a solution of a polymeric compound containing free hydroxyl groups, e.g. polyvinyl alcohols, mixed polymerization products of the kind obtainable by saponifying a mixed polymerization product from vinyl acetate and, for instance, maleic anhydride, or derivatives of polyvinyl alcohols in which the hydroxy groups are partially etherified or esterified, in so far as such derivatives are still soluble in water.  The viscosity is increased to a greater extent if the mixture is maintained or rendered neutral or alkaline.  The products are useful as auxiliary products in the textile industry, e.g. for sizing.  In examples: (1) a polyvinyl alcohol (obtainable by saponifying polyvinyl acetate) is dissolved in water and a solution of borax is added, producing a jelly; (2) a polyvinyl alcohol (obtained by saponifying polyvinyl chloracetate by means of ammonia) is dissolved in water and a solution of sodium borate is added, producing a solid jelly; (3) polyvinyl acetate is dissolved in methanol and the solution heated to 70 DEG  C. with the addition of sulphuric acid and a solution of borofluoroacetic acid in glacial acetic acid, yielding a powder which is dried and dissolved in water to produce a viscous solution; when this solution is neutralized with caustic soda solution it sets to a solid jelly; (4) boric acid is added at 50 DEG  C. to an aqueous solution of the reaction product of ethylene oxide on polyvinyl alcohol and the solution is neutralized, whereupon it solidifies and becomes gelatinous; a methyl or ethyl alcoholic solution of the polymeric substance may be similarly treated; (5) a product obtained by saponification of the mixed polymerization product from vinyl acetate and maleic anhydride is dissolved in water and a solution of sodium borate is added, whereby the viscosity is increased; (6) a product obtained by partially saponifying polyvinyl acetate is dissolved in ethyl alcohol, and pyridine or another base is added followed by a solution of boric acid in alcohol, the viscosity being thus increased.ALSO:As sizes for textiles may be employed the highly viscous products obtained by adding a boron compound, e.g. boric acid or salts thereof, boric anhydride, organic boron compounds such as boric acid esters, fluoboric acid or borofluoroacetic acid, to a solution of a polymeric compound containing free hydroxyl groups, e.g. polyvinyl alcohols, mixed polymerization products of the kind obtainable by saponifying a mixed polymerization product from vinyl acetate and, for instance, maleic anhydride, or derivatives of polyvinyl alcohols in which the hydroxy groups are partially etherified or esterified, in so far as such derivatives are still soluble in water.  If desired the mixture may be maintained or rendered neutral or alkaline, the viscosity thus being increased to a greater extent.  In examples: (1) a solution of borax is added to an aqueous solution of a polyvinyl alcohol; (2) a solution of sodium borate is added to an aqueous solution of a polyvinyl alcohol; (3) polyvinyl acetate is saponified in methanol solution by means of sulphuric acid in the presence of a solution of borofluoroacetic acid in glacial acetic acid, the product is dissolved in water and the solution neutralized; (5) boric acid is added to a solution of the reaction product of ethylene oxide on polyvinyl alcohol, in water or methyl or ethyl alcohol; (5) a solution of sodium borate is added to an aqueous solution of the product obtained by saponifying the mixed polymerization product from vinyl acetate and maleic anhydride; (6) pyridine and an alcoholic solution of boric acid are added to an alcoholic solution of a product of partial saponification of polyvinyl acetate.