Propylene polymers incorporating macromers

Details Propylene polymers incorporating macromers Propylene polymers incorporating macromers

2001-03-26

2002-01-29

Wu, David W. (Department: 1713)

Synthetic resins or natural rubbers -- part of the class 520 ser

Synthetic resins

Polymers from only ethylenic monomers or processes of...

C160S348000, C160S903000

Reexamination Certificate

active

06342574

ABSTRACT:

FIELD OF THE INVENTION
The present invention relates to propylene polymers incorporating macromers and a method for the preparation of branched polypropylene utilizing chiral, stereorigid transition metal catalyst compounds.
BACKGROUND OF THE INVENTION
Polypropylene and related polymers are known to have low melt strength. This is a significant deficiency in key application areas such as thermoforming and blow molding. Polyethylene on the other hand is used extensively in blown film applications requiring good melt strength. The limitations in the melt strength of polypropylenes show up as excess sag in sheet extrusion, rapid thinning of walls in parts thermoformed in the melt phase, low draw-down ratios in extrusion coating, poor bubble formation in extrusion foam materials, and relative weakness in large-part blow molding. Thus, it would be highly desirable to produce polypropylene and related polymers having enhanced melt strength as well as commercially valuable processability.
Increasing the melt strength of polymers such as polypropylene has been an industrial goal for well over ten years, however, success has been limited. The desirable properties that have made low density polyethylene commercially successful are attributed in large part to high melt strength and excellent processability. Both of these properties are attributed to the presence of long chain branching which is thought to occur under high pressure polymerization conditions.
There has been some success in increasing the melt strength of polypropylene. For example, EP 190 889 A2 discloses high energy irradiation of polypropylene to create what is believed to be polypropylene having substantial free-end long branches of propylene units. EP 384 431 discloses the use of peroxide decomposition of polypropylene in the substantial absence of oxygen to obtain a similar product.
Other attempts to improve the melt properties of polypropylene include U.S. Pat. No. 5,541,236, which introduces long chain branching by bridging two PP backbones to form H-type polymers, and U.S. Pat. No. 5,514,761, which uses dienes incorporated in the backbones to achieve a similar effect. However, it is difficult to avoid cross-linking and gel formation in such processes.
Thus, there is still a need for propylene polymers having improved melt strength and good processability.
SUMMARY OF THE INVENTION
The present invention meets that need by providing a polyolefin composition consisting essentially of isotactic polypropylene and, optionally, one or more comonomers, wherein the total comonomer content of the polyolefin composition is from 0 to 20 mole percent, and further, wherein the weight average branching index g′ for the lower molecular weight region of the polyolefin composition is less than 0.93. Additionally, a process is provided for producing a polyolefin composition comprising:
a) contacting, in solution, at a temperature from about 90° C. to about 120° C., propylene monomers with a catalyst composition comprising a first chiral, stereorigid transition metal catalyst compound capable of producing isotactic polypropylene;
b) copolymerizing the product of a) with propylene and, optionally, one or more copolymerizable monomers, in a polymerization reactor under suitable polypropylene polymerization conditions using a second chiral, stereorigid transition metal catalyst capable of producing isotactic polypropylene; and
c) recovering a branched olefin polymer.


REFERENCES:
patent: 4530914 (1985-07-01), Ewen et al.
patent: 4542199 (1985-09-01), Kaminsky et al.
patent: 4543399 (1985-09-01), Jenkins, III et al.
patent: 4588790 (1986-05-01), Jenkins, III et al.
patent: 4665208 (1987-05-01), Welborn, Jr. et al.
patent: 4701432 (1987-10-01), Welborn, Jr.
patent: 4769910 (1988-09-01), Noon
patent: 4808561 (1989-02-01), Welborn, Jr.
patent: 4871705 (1989-10-01), Hoel
patent: 4874734 (1989-10-01), Kioka et al.
patent: 4892851 (1990-01-01), Ewen et al.
patent: 4908463 (1990-03-01), Bottleberghe
patent: 4916198 (1990-04-01), Scheve et al.
patent: 4921825 (1990-05-01), Kioka et al.
patent: 4923833 (1990-05-01), Kioka et al.
patent: 4924018 (1990-05-01), Bottleberghe
patent: 4933403 (1990-06-01), Kaminsky et al.
patent: 4937299 (1990-06-01), Ewen et al.
patent: 4952540 (1990-08-01), Kioka et al.
patent: 4968827 (1990-11-01), Davis
patent: 5017714 (1991-05-01), Welborn, Jr.
patent: 5028670 (1991-07-01), Chinh et al.
patent: 5057475 (1991-10-01), Canich et al.
patent: 5091352 (1992-02-01), Kioka et al.
patent: 5103031 (1992-04-01), Smith, Jr.
patent: 5120867 (1992-06-01), Welborn, Jr.
patent: 5132281 (1992-07-01), Chevallier et al.
patent: 5132381 (1992-07-01), Winter et al.
patent: 5149819 (1992-09-01), Satoh et al.
patent: 5155080 (1992-10-01), Elder et al.
patent: 5157137 (1992-10-01), Sangokoya
patent: 5198401 (1993-03-01), Turner et al.
patent: 5204419 (1993-04-01), Tsutsui et al.
patent: 5206199 (1993-04-01), Kioka et al.
patent: 5235081 (1993-08-01), Sangokoya
patent: 5239022 (1993-08-01), Winter et al.
patent: 5240894 (1993-08-01), Burkhardt et al.
patent: 5243001 (1993-09-01), Winter et al.
patent: 5248801 (1993-09-01), Sangokoya
patent: 5276208 (1994-01-01), Winter et al.
patent: 5278119 (1994-01-01), Turner et al.
patent: 5278264 (1994-01-01), Spaleck et al.
patent: 5296434 (1994-03-01), Karl et al.
patent: 5304614 (1994-04-01), Winter et al.
patent: 5308815 (1994-05-01), Sangokoya
patent: 5318935 (1994-06-01), Canich et al.
patent: 5324800 (1994-06-01), Welborn, Jr. et al.
patent: 5350723 (1994-09-01), Dyer
patent: 5352749 (1994-10-01), DeChellis et al.
patent: 5391790 (1995-02-01), Rohrmann et al.
patent: 5405922 (1995-04-01), DeChellis et al.
patent: 5436304 (1995-07-01), Griffin et al.
patent: 5504171 (1996-04-01), Etherton et al.
patent: 5510502 (1996-04-01), Sugano et al.
patent: 5514761 (1996-05-01), Etherton et al.
patent: 5516848 (1996-05-01), Canich et al.
patent: 5541236 (1996-07-01), DeNicola, Jr. et al.
patent: 5554668 (1996-09-01), Scheve et al.
patent: 5589549 (1996-12-01), Govoni et al.
patent: 5591785 (1997-01-01), Scheve et al.
patent: 5643847 (1997-07-01), Walzer, Jr.
patent: 5747160 (1998-05-01), Pinoca et al.
patent: 5955557 (1999-09-01), Machida et al.
patent: 6117962 (2000-09-01), Weng et al.
patent: 0 190889 (1986-08-01), None
patent: 0 277 003 (1988-03-01), None
patent: 0 277 004 (1988-03-01), None
patent: 0 279 586 (1988-08-01), None
patent: 0 279 863 (1988-08-01), None
patent: 0 320 762 (1989-06-01), None
patent: 0 354 893 (1990-02-01), None
patent: 0 426 637 (1991-05-01), None
patent: 0 495 375 (1992-07-01), None
patent: 0 500 944 (1992-09-01), None
patent: 0 520 732 (1992-12-01), None
patent: 0 561 476 (1993-09-01), None
patent: 0 570 982 (1993-11-01), None
patent: 0 573 403 (1993-12-01), None
patent: 0 577 581 (1994-01-01), None
patent: 0 578 838 (1994-01-01), None
patent: 0 594 218 (1994-04-01), None
patent: 0 384 431 b (1994-11-01), None
patent: WO 91/09882 (1991-11-01), None
patent: WO 92/00333 (1992-09-01), None
patent: WO 92/10066 (1992-11-01), None
patent: WO 93/19108 (1993-09-01), None
patent: WO 94/03506 (1994-02-01), None
patent: WO-94/07930 (1994-04-01), None
patent: WO 94/07930 (1994-04-01), None
patent: WO 95/11931 (1994-04-01), None
patent: WO 94/10180 (1994-05-01), None
patent: WO 94/28034 (1994-08-01), None
patent: WO 96/00243 (1996-01-01), None
patent: WO 96/00245 (1996-01-01), None
patent: WO 96/04319 (1996-02-01), None
patent: WO 96/23010 (1996-08-01), None
Experimental Methods in Catalyst Research, vol. 1, Academic Press, 1968, pp. 67-96.
Journal of Organometallic Chemistry, v. 288, pp. 63-67 (1958).
“The Influence of Aromatic Substituents on the Polymerization Behavior of Bridged Zirconocene Catalysts”, W. Spaleck, et al.,Organometallics, 1994, 13, 954-963.
“ansa-Zironocene Polymerization Catalysts with Annelated Ring Ligands-Effects on Catalytic Activity and Polymer Chain Lengths”, H. Brinzinger, et al.,Organometallic, 1994, 13, 964-970.
Journal of Chem. Phys., B. H. Zimm and W. H. Stockmayer, 17, 1301 (1949).
“Bivariate Chain Length and Long Chain Branching Distribution for Co

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