POLYURETHANE COMPOSITION FOR PROTECTIVE COATING OF INTERNAL SURFACE OF OIL AND GAS EQUIPMENT Russian patent published in 2020 - IPC C09D175/04 

FIELD: paint and varnish materials.

SUBSTANCE: invention relates to paint materials and can be used for protection of inner surface of tanks, oil and gas pipelines, as well as other oil and gas equipment, in particular, internal surface of oil-field pipes from corrosion caused by action of water and aggressive chemical media, asphalt-resin-paraffin and salt deposits. Described is a polyurethane composition for protective coating of inner surface of oil and gas equipment, comprising a diisocyanate component, a hydroxyl-containing component and a solvent, where as a hydroxyl-containing component it contains pentaerythritol in ratio of diisocyanate component : pentaerythritol in terms of number of -NCO and -OH groups from 25:1 to 35:1, respectively, the solvent used is o-xylene and further includes a polyurethanation catalyst, a plasticiser and a wetting agent, with the following ratio of components, wt%: diisocyanate component 72.00–76.00, pentaerythritol 0.94–0.98, plasticiser 7.20–7.60, wetting agent 0.02–0.04, polyurethanation catalyst 0.05–0.06, o-xylene – balance.

EFFECT: high chemical resistance and strength properties of coatings.

1 cl, 2 tbl, 4 ex