COMPOSITION FOR COATING, METHOD OF PRODUCTION THEREOF AND SUBSTRATE WITH COATING MADE THEREFROM Russian patent published in 2008 - IPC C09D123/08 C08F210/16 

FIELD: chemistry.

SUBSTANCE: composition includes multimodal ethylene polymer, containing 80 to 99.8% weight of repeating ethylene units and 0.2 to 20% weight of repeating C₃-C₂₀ α-olefine units, and represents a mixture of, at least, the first and the second polymers, which can be obtained by method including at least two stages, in which the first ethylene polymer is obtained by polymerisation of ethylene and possible co-monomer(s) in presence of catalytic system of metallocene type with one active centre, the second ethylene polymer being obtained by polymerisation of ethylene and possible co-monomer(s) in presence of catalytic system of metallocene type with one active centre. The said stages are carried out in any sequence and ethylene polymer of each stage is present at the following stage(s). Mixture of 20 to 80% weight, of the first ethelene polymer and 80 to 20% weight, of the second one is obtained, where fraction of low-molecular ethylene polymer belonging to any of the aforesaid first and second ethylene polymers has the rate of melt flow MFR₂ 50-500 g/10 minute, the said mixture having density of 0.915 to 0.955 g/cm³, rate of melt flow, MFR₂, from 0.028 to 1.5 g/10 minutes, molecular-mass distribution, Mw/Mn, from 3 to 10, and the value of burst strength of 5.0 MPa according to ISO 6259, at least, 500 hrs. Substrate covered with the composition for coating is preferably a metal pipe.

EFFECT: obtaining new composition for coating with high density and rate of melt flow.

27 cl, 2 ex