Propylene polymers incorporating macromers

Details Propylene polymers incorporating macromers Propylene polymers incorporating macromers

1998-02-06

2001-03-06

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...

C526S348000, C526S943000

Reexamination Certificate

active

06197910

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, repeating units of one or more comonomers, wherein the total comonomer repeating unit 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: 4335225 (1982-06-01), Collette et al.
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: 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), Bottelberghe
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), Bottelberghe
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: 5026789 (1991-06-01), Canich
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: 5132381 (1992-07-01), Winter 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: 5329032 (1994-07-01), Tran et al.
patent: 5352749 (1994-10-01), DeChellis et al.
patent: 5391629 (1995-02-01), Turner 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: 5504169 (1996-04-01), Canich
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: 5539056 (1996-07-01), Yang 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: 0 190 889 B1 (1986-08-01), None
patent: 190889 (1986-08-01), None
patent: 0 279 863 B1 (1988-08-01), None
patent: 0 277 003 A1 (1988-08-01), None
patent: 0 279 586 B1 (1988-08-01), None
patent: 0 277 004 A1 (1988-08-01), None
patent: 0 320 762 B1 (1989-06-01), None
patent: 0 354 893 B1 (1990-02-01), None
patent: 0 366 411 A2 (1990-05-01), None
patent: 0 426 637 A2 (1991-05-01), None
patent: 0 495 375 A2 (1992-07-01), None
patent: 0 500 944 A1 (1992-09-01), None
patent: 0 520 732 A1 (1992-12-01), None
patent: 0 573 403 (1993-08-01), None
patent: 0 561 476 A1 (1993-09-01), None
patent: 0 570 982 A1 (1993-11-01), None
patent: 0 573 403 A2 (1993-12-01), None
patent: 0 578 838 A1 (1994-01-01), None
patent: 0 577 581 A2 (1994-01-01), None
patent: 0 594 218 A1 (1994-04-01), None
patent: 0 384 431 B1 (1994-11-01), None
patent: 384431 (1994-11-01), None
patent: H4-337308 (1992-01-01), None
patent: WO 91/09882 (1991-07-01), None
patent: WO 92/00333 (1992-01-01), None
patent: WO 93/19103 (1993-09-01), None
patent: WO 94/07930 (1994-04-01), None
patent: WO 95/11931 (1994-04-01), None
patent: WO 94/07928 A1 (1994-04-01), None
patent: WO 94/03506 (1994-05-01), None
patent: WO 94/10180 (1994-05-01), None
patent: WO 94/28034 (1994-12-01), None
patent: WO 95/25757 (1995-09-01), None
patent: WO 96/23010 (1996-01-01), None
patent: WO 96/00243 (1996-01-01), None
patent: WO 96/04319 (1996-02-01), None
patent: WO 96/00245 (1996-04-01), None
patent: WO 96/23838 A1 (1996-08-01), None
patent: WO 97/43321 A1 (1997-11-01), None
patent: WO 98/34970 (1998-08-01), None
“Structures and Properties of Block Polymers and Multiphase Polymer Systems: An overview of Present Status and Future Potential”, S.L. Aggarwal, Sicth Biennial Manchester Polymer Symposium (UMIST Manchester, Mar. 1976).
“Properties of Isota

Affiliated with

Also associated with

Rating

Propylene polymers incorporating macromers does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Propylene polymers incorporating macromers, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Propylene polymers incorporating macromers will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2496198