PROTECTIVE COATINGS AND PAINTS WITH LOW CONTENT OF VOLATILE ORGANIC COMPOUNDS Russian patent published in 2010 - IPC C09D133/06 C09D133/02 C09D109/00 C09D5/02 C08L101/00 C08F2/22 C08F220/62 C08K5/10 

FIELD: chemistry.

SUBSTANCE: invention relates to protective coating compositions. The self-oxidisable protective coating composition contains a liquid aqueous dispersion medium and binder. The binder contains an unsaturated copolymer which contains i) not less than one unsaturated fatty acid of drying oil obtained from a reaction of an unsaturated fatty acid with the epoxy group of an ethylene unsaturated monomer and ii) one or more monomers which copolymerise with i), where not less than 15% of the mass of the binder is in form of microgel. Particles of the microgel have size of 20-750 nm. The unsaturated copolymer has maximum calculated Fox glass transition temperature (T_g) of 8°C. The copolymerising monomer is an acrylic monomer obtained from esters of acrylic and methacrylic acids, esters of acrylic and methacrylic acids and aliphatic or aromatic alcohols, styrene, substituted styrene, vinylcarboxylate esters and olefins selected from ethylene, propylene, butene-1 and styrenes and homopolymers thereof. Described also is a dispersion of particles of an unsaturated copolymer for a self-oxidisable coating, method of preparing the dispersion and a protective coating made from the self-oxidisable composition described above. The method of preparing a dispersion of particles of an unsaturated copolymer involves emulsion copolymerisation of an unsaturated fatty acid of drying oil and copolymerisable monomers using a redox initiation system. Polymerisation takes place at 30-45°C. The redox initiation system is taken in amount of 0.15-0.50% of the total mass of the monomers.

EFFECT: disclosed self-oxidisable composition enables to obtain a protective coating with good physical and mechanical characteristics.

23 cl, 5 tbl, 24 ex