Abstract: Modified melamine-formaldehyde resins are made of a condensate of formaldehyde, urea, melamine and modifying agents which contains: (a) a combination of 5 to 25 wt %, with respect to melamine, of dicyanodiamide and 8 to 30 wt %, with respect to melamine, of water-soluble polyalcohol with at least two hydroxyalkyl groups, and/or (b) 1.5 to 20 wt % amines having the formulas (Ia)NR.sub.4 R.sub.5 --R.sub.1 --X (Ia)and/or (Ib),NR.sub.4 R.sub.5 --R.sub.2 --Y--R.sub.3 --X (Ib)in which R.sub.1 and R.sub.3 are the same or different and depending on the meaning of X stand for a linear, branched or cyclic C.sub.1 -C.sub.12 alkyl or alkylene radical and R.sub.2 stands for a linear, branched or cyclic C.sub.1 -C.sub.12 alkylene radical; R.sub.4 and R.sub.5 can be the same or different and can stand for H or for a linear or branched C.sub.1 -C.sub.12 alkyl radical; and X can stand for hydrogen, OH or NR.sub.4 R.sub.5 and Y can stand for --O-- or --NH--. The molar ratio of melamine to formaldehyde ranges from 1:1.

Abstract: Aqueous dispersions of urethane-acrylic polymers, giving coatings resistant to alkalies and organic solvents, are obtained by starting from organic polyisocyanates and mixtures consisting of macroglycols and polyols containing ionizable groups and at least one ethylenic unsaturation.

Abstract: Composition based on a urea-formaldehyde polycondensate, suitable for the preparation of solid foams to be used as thermal insulating materials, characterized in that said composition contains hexamethylenetetramine in quantities comprised between 2% and 15% by weight with respect to the content of dry product of the composition.