Polyethylene composition for biaxial orientation
AssigneeNOVA Chemicals (International) S.A.
InventorsMaryam Fereydoon, Shivendra Goyal, Sepideh Kasiri, Owen Lightbody, Norman Aubee, Bronwyn Gillon
Life of this patent
Estimating the term…
Abstract
A polyethylene composition has a density of from 0.941 to 0.962 g/cm3; a melt index, I2 of from 0.5 to 5.0 g/10 min; a melt flow ratio, I21/I2 of ≥40; a Z-average molecular weight distribution, Mz/Mw of ≥2.5; a comonomer distribution breadth index, CDBI50 of >50 wt %; and a long chain branching factor, LCBF of >0.0010. In a temperature rising elution fractionation (CTREF) analysis, the polyethylene composition has greater than 70 weight percent of material eluting at a temperature of greater than 90° C.
Claims28
A polyethylene composition comprising:
- (i) from 5 to 50 weight % of first ethylene copolymer having a weight average molecular weight, Mw of from 170,000 g/mol to 470,000 g/mol;
- and
- (ii) from 95 to 50 weight % of a second ethylene copolymer;
- wherein the first ethylene copolymer has a higher weight average molecular weight, Mw than the second ethylene copolymer;
- wherein the ratio (SCB1/SCB2) of the number of short chain branches per thousand carbon atoms in said first ethylene copolymer (SCB1) to the number of short chain branches per thousand carbon atoms in said second ethylene copolymer (SCB2) is from 0.8 to 3.5;
- wherein the polyethylene composition has a density of from 0.941 to 0.962 g/cm3;
- a melt index, I2 of from 0.5 to 5.0 g/10 min;
- a melt flow ratio, I21/I2 of ≥40;
- a Z-average molecular weight distribution, Mz/Mw of ≥2.5;
- a comonomer distribution breadth index, CDBI50 of >50 wt %;
- a long chain branching factor, LCBF of >0.0010;
- and
- wherein in a temperature rising elution fractionation (CTREF) analysis, the polyethylene composition has greater than 70 weight percent of material eluting at a temperature of greater than 90° C.
A biaxially oriented polyethylene film comprising a polyethylene composition, the polyethylene composition comprising:
- (i) from 5 to 50 weight % of first ethylene copolymer having a weight average molecular weight, Mw of from 170,000 g/mol to 470,000 g/mol;
- and
- (ii) from 95 to 50 weight % of a second ethylene copolymer;
- wherein the first ethylene copolymer has a higher weight average molecular weight, Mw than the second ethylene copolymer;
- wherein the ratio (SCB1/SCB2) of the number of short chain branches per thousand carbon atoms in said first ethylene copolymer (SCB1) to the number of short chain branches per thousand carbon atoms in said second ethylene copolymer (SCB2) is from 0.8 to 3.5;
- wherein the polyethylene composition has a density of from 0.941 to 0.962 g/cm3;
- a melt index, I2 of from 0.5 to 5.0 g/10 min;
- a melt flow ratio, I21/I2 of ≥40;
- a Z-average molecular weight distribution, Mz/Mw of ≥2.5;
- a comonomer distribution breadth index, CDBI50 of >50 wt %;
- a long chain branching factor, LCBF of >0.0010;
- and
- wherein in a temperature rising elution fractionation (CTREF) analysis, the polyethylene composition has greater than 70 weight percent of material eluting at a temperature of greater than 90° C.
Dependencies are inferred from the claim text.