Isotactic propylene copolymers, their preparation and use

A propylene/ethylene copolymer comprising at least about 60 weight percent of units derived from propylene and at least about 0.1 weight percent of units derived from ethylene, the copolymer characterized as having a skewness index, Six, greater than about −1.20.

A propylene/ethylene copolymer comprising at least about 60 weight percent of units derived from propylene and at least about 0.1 weight percent of units derived from ethylene, the copolymer characterized as having a DSC curve with a Tme that remains essentially the same and a Tmax that decreases as the amount of ethylene in the copolymer is increased.

A propylene/ethylene copolymer comprising at least about 60 weight percent of units derived from propylene and at least about 0.1 weight percent of units derived from ethylene, the copolymer characterized as having an X-ray diffraction pattern exhibiting more gamma-form crystals than a propylene/ethylene copolymer comparable in weight average molecular weight except that it is prepared with a Ziegler-Natta catalyst.

A propylene/ethylene copolymer comprising at least about 60 weight percent of units derived from propylene and at least about 0.1 weight percent of units derived from ethylene, the copolymer characterized as having a B-value greater than about 1.4 when the ethylene content of the copolymer is at least about 3 weight percent.

A copolymer of propylene and an unsaturated monomer other than ethylene, the copolymer comprising at least about 60 weight percent of units derived from propylene and at least about 0.1 weight percent of units derived from the unsaturated monomer, the copolymer characterized as having 13C NMR peaks corresponding to a regio-error at about 14.6 and about 15.7 ppm, the peaks of about equal intensity.

A copolymer of propylene and an unsaturated monomer other than ethylene, the copolymer comprising at least about 60 weight percent of units derived from propylene and at least about 0.1 weight percent of units derived from the unsaturated monomer, the copolymer characterized as having a skewness index, Six, greater than about −1.20.

A copolymer of propylene and an unsaturated monomer other than ethylene, the copolymer comprising at least about 60 weight percent of units derived from propylene and at least about 0.1 weight percent of units derived from the unsaturated monomer, the copolymer characterized as having a DSC curve with a Tme that remains essentially the same and a Tmax that decreases as the amount of ethylene in the copolymer is increased.

A copolymer of propylene and an unsaturated monomer other than ethylene, the copolymer comprising at least about 60 weight percent of units derived from propylene and at least about 0.1 weight percent of units derived from the unsaturated monomer, the copolymer characterized as having an X-ray diffraction pattern exhibiting more gamma-form crystals than a propylene/unsaturated copolymer comparable in monomer and weight average molecular weight except that it is prepared with a Ziegler-Natta catalyst.

A copolymer of propylene and an unsaturated monomer other than ethylene, the copolymer comprising at least about 60 weight percent of units derived from propylene and at least about 0.1 weight percent of units derived from the unsaturated monomer, the copolymer characterized as having a B-value greater than about 1.3 when the unsaturate monomer content of the copolymer is at least about 3 weight percent.

A blend of at least two polymers in which at least one polymer (a) comprises at least about 60 weight percent of units derived from propylene and at least about 0.1 weight percent of units derived from a comonomer selected from the group consisting of ethylene and an unsaturated monomer other than ethylene, and (b) is characterized as having at least one of the following properties:

• (i) 13 C NMR peaks corresponding to a regio-error at about 14.6 and about 15.7 ppm, the peaks of about equal intensity, (ii) a B-value greater than about 1.4 when the comonomer content of the copolymer is at least about 3 weight percent (iii) a skewness index, Six, greater than about −1.20, (iv) a DSC curve with a Tme that remains essentially the same and a Tmax that shifts to the left as the amount of comonomer in the copolymer is increased, and (v) an X-ray diffraction pattern that exhibits more gamma-form crystals than a copolymer comparable in all respects except that it is prepared with a Ziegler-Natta catalyst.

A blend of (A) at least one propylene homopolymer characterized as having

• 13C NMR peaks corresponding to a regio-error at about 14.6 and about 15.7 ppm, the peaks of about equal intensity, and (B) at least one polymer other than a copolymer (1) comprising at least about 60 weight percent of units derived from propylene and at least about 0.1 weight percent of units derived from a comonomer selected from the group consisting of ethylene and an unsaturated monomer other than ethylene, and (2) is characterized as having at least one of the following properties:
• (i) 13C NMR peaks corresponding to a regio-error at about 14.6 and about 15.7 ppm, the peaks of about equal intensity, (ii) a B-value greater than about 1.4 when the comonomer content of the copolymer is at least about 3 weight percent (iii) a skewness index, Six, greater than about −1.20, (iv) a DSC curve with a Tme that remains essentially the same and a Tmax that shifts to the left as the amount of comonomer in the copolymer is increased, and (v) an X-ray diffraction pattern that exhibits more gamma-form crystals than a copolymer comparable in all respects except that it is prepared with a Ziegler-Natta catalyst.

A process for making an polymer comprising propylene and ethylene, the polymer comprising at least about 60 weight percent of units derived from propylene and at least about 0.1 weight percent of units derived from ethylene, the process comprising contacting propylene and ethylene under polymerization conditions with a nonmetallocene, metal-centered, heteroaryl ligand catalyst in combination with at least one activator.

A process for making an polymer free of units derived from ethylene, the polymer comprising at least about 60 weight percent of units derived from propylene and at least about 0.1 weight percent of units derived from an unsaturated monomer other than ethylene, the process comprising contacting propylene and the unsaturated comonomer under polymerization conditions with a nonmetallocene, metal-centered, heteroaryl ligand catalyst in combination with at least one activator.

A process for making an isotactic propylene polymer, the polymer (A) comprising at least about 60 weight percent of units derived from propylene and at least about 0.1 weight percent of units derived from a comonomer of at least one of ethylene and an unsaturated monomer other than ethylene, and (B) characterized as having at least one of the following properties:

• (i) 13C NMR peaks corresponding to a regio-error at about 14.6 and about 15.7 ppm, the peaks of about equal intensity, (ii) a B-value greater than about 1.4 when the comonomer content of the copolymer is at least about 3 weight percent (iii) a skewness index, Six, greater than about −1.20, (iv) a DSC curve with a Tme that remains essentially the same and a Tmax that shifts to the left as the amount of comonomer in the copolymer is increased, and (v) an X-ray diffraction pattern that exhibits more gamma-form crystals than a copolymer comparable in all respects except that it is prepared with a Ziegler-Natta catalyst., the process comprising contacting under polymerization conditions propylene and ethylene with a nonmetallocene, metal-centered, heteroaryl ligand catalyst in combination with at least one activator.

A solution phase process for making a high weight average molecular weight (Mw), narrow molecular weight distribution (MWD) polymer, the polymer comprising at least about 60 weight percent of units derived from propylene and at least about 0.1 weight percent of units derived from a comonomer of at least one of ethylene and an unsaturated comonomer other than ethylene, the process comprising contacting propylene and at least one of ethylene and an unsaturated comonomer under solution phase polymerization conditions with a nonmetallocene, metal-centered, heteroaryl ligand catalyst.