Patent GB-700809-A (GB)
Title: Improvements in or relating to nitrogen-containing thermosetting resins including organic sulphonate residues and to a process for preparing the same
IPC: C08G12/40
Filed: 1950-10-16
Abstract: Nitrogen containing thermosetting resins containing organic sulphonate residues are prepared by condensing in water urea, thiourea, cyanamide, dicyandiamide, guanidine, or an aminototriazine, with an aldehyde and ,05-,5 mol. per mol. of the NH2 compound of a water soluble salt of a phenol sulphonic acid or of a hydroxy sulphonic acid of the general formula Y - CH (R) - CH2 - SO3H (when Y = OH and R = phenyl; or Y = H and R = hydroxy alkoxy with not more than 4 carbon atoms).  Amino - triazines mentioned are melamine, 2 - chloro - 4.6 - diamino - 1, 3, 5, - triazine, and 2 - hydroxy - 4, 6 - diamino - 1, 3, 5 - triazine.  Mixtures of the NH2 - containing compounds may be employed.  Aldehydes mentioned are formaldehyde, its polymers, acetaldehyde, propionaldehyde, benzaldehyde and furfural. Sulphonic acids mentioned are phenol sulphonic acids (p and/or o, or mixtures of o, m and p), phenyl isothionic acid and b  - hydrox - b 1 - sulpho - diethyl ether or its propyl or butyl analogues.  Sodium, potassium or lithium salts may be used.  Preferred proportions are 2 - 6 mols. of aldehyde mol. of NH2-containing compound.  Preferably the methylol compound is formed in alkaline solution, concentrated and reacted with the salt in acid medium.  With urea and similar compounds the pH of the reaction mixture is preferably 7.0-8.5 initially and 4.0 - 6.0 after addition of the salt.  With melamine and like compounds the pH may be 7.0 - 10.0.  Products may be used for ion-exchange, treating textiles (see Group IV (c)) and especially for addition to paper pulp (see Group VIII).  The methylol compound is concentrated before reaction with the salt preferably by flash evaporation, e.g. by passage through a heated pipe so that a small portion of the issuing solution is rapidly concentrated.  Vacuum may be employed.  After concentration the solution is acidified with, e.g. sulphuric or phosphoric acid. Resin solutions for addition to paper pulp are stabilized by neutralization.  They may be evaporated to dryness to yield solid products.  In examples (1) 1 mol. urea, 2.7 mols. aqueous formaldehyde were adjusted with caustic soda to a pH of 7.5 - 7.9 and heated.  A mixture of o and p-phenol sodium sulphonate (98 per cent. p - isomer) was added and the solution concentrated under reduced pressure to 60 per cent. solids.  Sulphonic acid was added to pH5 and the mixture refluxed with stirring to a viscosity of 5 poises.  The product was neutralized with caustic soda and cooled. It was added to paper pulp for high wet strength paper. Other examples are similar but employ: (2) melamine in place of urea, (3) the sodium salt of phenyl isothionic acid, (4) b  - hydroxy - b 1 - sodium sulpho - diethyl ether, (5) melamine, formaldehyde and b  - hydroxy - b  - sodium sulphodiethyl ether.ALSO:Water soluble condensation products of an aldehyde with urea, thiourea, cyanamide, dicyandiamide, guanidine or an aminotriazine and a water-soluble salt of certain hydroxy sulphonic acids [see Group IV(a)] are used for treating textiles such as cotton or wool yarns or fabrics.  In examples II an aqueous solution of a condensation product of melamine, formaldehyde and the sodium salt of mixed o- and p-phenol sulphonic acids (98 per cent para isomer) was used to provide a shrinkproof finish on textile fabrics.  V The condensate was prepared from melamine, formaldehyde and b -hydroxy-b \sv-sodium sulpho-diethyl ether.