Coating composition, method of preparation thereof and substrate coated therewith

摘要

A coating composition, a process for producing it and substrate coated therewith are described. The composition comprises a multimodal ethylene polymer, which contains from 80 to 99.8% by weight of ethylene repeating units and from 0.2 to 20% by weight of C3-C20 α-olefin repeating units, and is a blend of at least a first and a second ethylene polymer prepared by polymerization in the presence of a single site catalyst system.;The blend has a density of 0.915-0.955 g/cm3, a melt flow rate, MFR2, of 0.028-1.5 g/10 min., a molecular weight distribution, Mw/Mn, of 3-10, and a CTL 5.0 MPa-value according to ISO 6259 of at least 500 hrs.

主权项

1. A coating composition, comprising a multimodal ethylene polymer, containing from 80 to 99.8% by weight of ethylene repeating units and from 0.2 to 20% by weight of C3-C20 α-olefin repeating units, and is a blend of at least a first ethylene polymer and a second ethylene polymer resulting from a process comprising at least two steps in which:
said first ethylene polymer being a low molecular weight fraction and is prepared by polymerising ethylene and optional comonomer(s) in the presence of a single site catalyst system, wherein the first ethylene polymer has a melt flow rate, MFR2, of 100-300 g/10 min; and said second ethylene polymer being a high molecular weight fraction and is prepared by polymerising ethylene and optional comonomer(s) in the presence of a single site catalyst system; said steps being performed in any order and the ethylene polymer of each step being present in the following step(s), and producing a blend of from 40 to 60% by weight of said first ethylene polymer and from 60 to 40% by weight of said second ethylene polymer, said blend having a density of 0.915-0.955 g/cm3, a melt flow rate, MFR2, of 0.05-1 g/10 min., a molecular weight distribution, Mw/Mn, of 3-10, and a CTL 5.0 MPa-value according to ISO 6252 of at least 12000 hrs.