Patent GB-905039-A (GB)
Title: Process of preparing resinous material
IPC: C08G12/36
Filed: 1958-11-04
Abstract: A resinous material is produced by condensing under alkaline conditions at least 1 mol. of a mono-aldehyde with 1 mol. of an aminotriazine, a urea or a phenol, and between 0,1 and 2 mols. of a methylol amino methane per mol. of free aldehyde calculated or determined in the manner hereinafter set forth.  The methylol amino methane may be added after initial reaction between the other two ingredients but while the resin still has a water tolerance of 100%, or in the case of melamine resins of at least 400%.  In this case the amount of free aldehyde present is determined by analysis, but, if desired all three reactants may be mixed at the same time, after a preliminary determination of the amount of free aldehyde left after a trial reaction of given duration without any methylol aminomethane present.  The methylolaminomethane corresponds with the formula <FORM:0905039/IV(a)/1> where n=0, 1 or 2, and R is methyl or ethyl. Suitable compounds are tris hydroxymethyl aminomethane; bis(hydroxymethyl) aminomethyl methane; bis(hydroxymethyl) aminoethyl methane; hydroxymethyl aminodimethyl methane; hydroxymethyl aminodiethyl methane; and hydroxymethyl aminoethyl methyl methane. Aldehydes mentioned are formaldehyde, acetaldehyde, benzaldehyde, furfural, acrolein, butyraldehyde, pentaldehyde or heptaldehyde. Suitable substances for reaction with the aldehyde are melamine, formoguanamine, acetoguanamine, benzoguanamine, ammeline and ammelide, urea, thiourea, methylene urea, ethylene urea, phenol, o, m, or p-cresol, resorcinol, xylenol, tert-butyl catechol, tert. butyl cresol, tert-butyl hydroquinone and the bis-phenols.  Aminoplast resins according to the invention may be alkylated or unalkylated. In the Examples (1), (2), (6) and (8) urea is reacted with formaldehyde in presence of triethanolamine and the product stabilized by addition of tris-hydroxymethylamino methane; (3) and (7) urea, formaldehyde, tris-hydroxymethylaminomethane and trithanolamine are all reacted together.  Example (4) is similar without the use of trithanolamine, and in Example (5) a second lot of tris-hydroxymethylaminomethane is added after 30 minutes refluxing. Examples (9) and (10) related to resorcinol-formaldehyde resins modified with trishydroxymethylaminomethane.  Examples (11)-(16) are broadly similar using phenol and formaldehyde, and Examples (17)-(22) relate to modified melamine-formaldehyde resins.  Uses.  The products may be used for making castings, paper or glass fabric laminates, for snagging wheels, as rock wool binders, for making insulation bats or particle boards. Resorcinolformaldyhyde resins are very reactive and gel quickly. They are useful as oil well cements or for filling subteranean cavities, e.g. in mines.  The urea resins are good for craze-resistant adhesives, for treating fabrics to give better handle or for treating paper or leather.  Other fillers mentioned for use with the resins of the invention are chopped rag, silica, slate dust, asbestos fibres, glass fibres, regenerated cellulose, rayon linen and kraft paper.  Conventional acid or latent acid curing catalysts may be used with the resins, or conventional modifiers, e.g. as described in Specifications 758,236 and 790,034.