Polyolefin containing a terminal phenyl or substituted...

Details Polyolefin containing a terminal phenyl or substituted... Polyolefin containing a terminal phenyl or substituted...

2001-01-08

2002-11-12

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...

C526S127000, C526S134000, C526S279000, C526S293000, C526S296000, C526S318100, C526S310000, C526S347000, C526S347100, C526S348000, C526S905000

Reexamination Certificate

active

06479600

ABSTRACT:

FIELD OF THE INVENTION
This invention relates to functional polyolefiln material that contains a terminal phenyl or substituted phenyl group, and to a process for its preparation. More particularly, this invention relates to a functional polymer having a polyolefin polymer backbone that is a homopolymer or copolymer prepared by metallocene coordination polymerization of linear, branched or cyclic C
3
-C
18
alpha-olefins and/or diolefins, in which the molecular weight of polyolefin backbone is above about 500 g/mole, preferably from about 10,000 to 1,000,000 g/mole. The process by which the functional polymer material is prepared involves a novel sequential chain transfer reaction, first to styrene (or a styrene derivative) and then hydrogen, during the transition metal mediated olefin polymerization, to produce polyolefin having a terminal phenyl or substituted phenyl group.
BACKGROUND OF THE INVENTION
Although useful in many commercial applications, polyolefins suffer a major deficiency, i.e., poor interaction with other materials. The inert nature of polyolefins significantly limits their end uses, particularly those in which adhesion, dyeability, paintability, printability or compatibility with other functional polymers is paramount. Polymers containing a terminal functional group are particularly desirable materials. For example, they can be used as interfacial agents during reactive extrusion processes to improve adhesion and compatibility in polymer blends and composites. Polymers containing a terminal functional group also can serve as reactive building blocks for the preparation of block and graft copolymers.
In general, the chemistry for introducing a functional group to the chain end of a vinyl polymer is very limited. Usually, these polymers are prepared by terminating living polymers with suitable reagents. The anionic, cationic, and metathesis living polymerizations are particularly preferred because they provide a stable propagating active site that can be converted effectively to the desired functional group at the polymer chain end. [For examples of anionic living polymerization, see, e.g., U.S. Pat. No. 3,265,765 and D. E. Bergbreiter et al,
J. Am. Chem. Soc
., 109, 174, 1987; for cationic living polymerization, see, e.g., U.S. Pat. No. 4,946,899; and for metathesis living polymerization, see, e.g., R. H. Grubbs, et al,
Macromolecules
, 22, 1558, 1989]. However, a corresponding termination process in transition metal coordination polymerization of alpha-olefins is very rare due to the generally non-living nature of transition metal olefin catalysis. Only a few examples of living transition metal coordination polymerization have been reported, and those have been accomplished under very inconvenient reaction conditions and using specific catalysts [see Y. Doi, et al,
Makromol. Chem
., 188, 1273, 1987
; Makromol. Chem
., 186, 1825, 1985
; Makromol. Chem. Rapid Comm
., 5, 811, 1984; and H. Yasuda, et al,
Macromolecules
, 25, 5115, 1992].
Several years ago, a new living catalyst system, based on late transition metals, e.g., cobalt (III) complex, was reported as being useful in the preparation of functional group-terminated polyethylene [see, M. Brookhart, et al,
Macromolecules
, 28, 5378, 1995]. The metal complex was first reacted with a phenyl group before initiating ethylene polymerization. In other words, the functional group was introduced into the beginning of polymer chain. To prevent the deactivation of the active site, the functional group had to be blocked from the electrophilic Co (III) during the polymerization. Overall, the catalyst activity was relatively low because each catalyst active site produced only one polymer chain. In addition, the polymer structure was limited to the branched polyethylene. To date, the applicants are unaware of any late transition metal catalyst that has been shown to incorporate alpha-olefins, such as propylene and 1-butene, with isotactic insertion into an olefin polymer backbone.
Another approach toward preparing functional group terminated polyolefin was via in situ chain transfer reaction to a co-initiator during Ziegler-Natta polymerization. Several Al-alkyl co-initiators [see, U.S. Pat. No. 5,939,495] and Zn-alkyl co-initiators [sere, Shiono et al.,
Makromol. Chem
., 193, 2751, 1992 and
Makromol. Chem. Phys
., 195, 3303, 1994] were found to engage chain transfer reactions to obtain Al and Zn-terminated polyolefins, respectively. The Al and Zn-terminated polyolefins can be further modified to prepare polyolefins having other terminal functional groups. However, the products comprise a complex mixture of polymers containing various end groups, due to ill-defined catalyst systems that also involve other chain transfer reactions, such as &bgr;-hydride elimination and chain transfer to monomer.
Another method reported for the preparation of functional group terminated polyolefin is based on chemical modification of chain end unsaturated polypropylene (PP), which can be prepared by metallocene polymerization or thermal degradation of high molecular weight PP. [see Chung et al,
Macromolecules
, 32, 2525, 1999
; Macromolecules
, 31, 5943, 1998
; Polymer
, 38, 1495, 1997; Mulhaupt et al,
Polymers for Advanced Technologies
, 4, 439, 1993; and Shiono et al,
Macromolecules
, 25, 3356, 1992
; Macromolecules
, 26, 2085, 1993
; Macromolecules
, 30 5997, 1997]. The effectiveness of this chain end functionalization process is strongly dependent on (a) the percentage of polymer chains having a vinylidene terminal group and (b) the efficiency of functionalization reaction. It has been observed that the efficiency of the functionalization reaction decreases with an increase of PP molecular weight, due to the decrease of vinylidene concentration. Some functionalization reactions are very effective for low molecular weight PP. However, they become very ineffective for PP polymer having a molecular weight in excess of about 30,000 g/mole. Unfortunately, for many applications, such as for improving the interfacial interactions in PP blends and composites, a high molecular weight PP chain is essential. In addition, the availability of chain-end unsaturated polyolefins is very limited and most polyolefins, except polypropylene, have a low percentage of chain end unsaturation in their polymer chains.
In general, developments in homogeneous metallocene catalysis have provided a new era in polyolefin synthesis [see, e.g., U.S. Pat. No. 4,542,199; U.S. Pat. No. 4,530,914; U.S. Pat. No. 4,665,047; U.S. Pat. No. 4,752,597; U.S. Pat. No. 5,026,798 U.S. Pat. No. 5,272,236]. Thus, with well-designed, single-site catalysts having a constrained ligand geometry, the incorporation of higher alpha-olefins into a polymer chain has been greatly enhanced. This has significantly expanded the scope (composition and molecular structure) of polyolefin material, and has enabled the preparation of a variety of polymers having narrow molecular weight and composition distributions, including linear low density polyethylene (LLDPE), poly(ethylene-co-styrene) [see, e.g., U.S. Pat. No. 5,703,187], poly(ethylene-co-p-methylstyrene ), poly(ethylene-ter-propylene-ter-p-methylstyrene) and poly(ethylene-ter-1 -octene-ter-p-methylstyrene) [see, e.g., U.S. Pat. Nos. 5,543,484 and 5,866,659].
The narrow molecular weight and composition distributions of the metallocene-prepared polyolefins are the results of a well-defined polymerization mechanism, including initiation, propagation, termination, and chain transfer reactions. In recent years, Marks and Chung have applied the well-defined chain transfer reaction to terminate a propagating polyolefin chain with silane reagents [see Marks, T. J.,
J. Am. Chem. Soc
., 120, 4019, 1998
; J. Am. Chem. Soc
., 117, 10747, 1995
; Macromolecules
, 32, 981, 1999] and with borane reagents [see Chung, T. C.,
J. Am. Chem. Soc
., 121, 6764, 1999
; Macromolecules
, 32, 8689, 2000]. Several organosilanes having Si-H groups an

Affiliated with

Also associated with

Rating

Polyolefin containing a terminal phenyl or substituted... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Polyolefin containing a terminal phenyl or substituted..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Polyolefin containing a terminal phenyl or substituted... will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2982139