Catalyst combination and a process for preparing linear,...

Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – Polymers from only ethylenic monomers or processes of...

Reexamination Certificate

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Details

C526S131000, C526S133000, C526S134000, C526S165000, C526S351000, C526S943000, C502S103000, C502S152000

Reexamination Certificate

active

06576726

ABSTRACT:

FIELD OF THE INVENTION
The present invention relates to a new catalyst composition and a process for preparing linear, isotactic polymers, wherein the isotacticity of the linear polymers due to a statistic distribution of stereoscopic errors in the polymer chain, being within the range of from 25 to 60% of pentad concentration.
BACKGROUND OF THE INVENTION
For a long time, isotactic polymers have been of interest as plastic materials for manufacturing articles of relatively good deformation resistance, such as sheathings of household appliances. In general, such isotactic polymers with propylene as monomer are highly crystalline nature and, therefore, are relatively hard with little or no impact resistance such that they are useful only in applications in which hardness or low impact resistance is desirable.
Most recently, various attempts have been made, aiming at preparing polypropylene with elastic characteristics. EP 0 707 016 A1 specifies a catalyst composition and a process for preparing polyolefins. The catalysts specified in EP 0 707 016 A1 are, in substance, made up of a metallocene compound having an indene ring and a fluorene ring which are bridged via C, Si or Ge. In case of the metallocene compound, it is essential that, in the indene ring system, at least the residue denoted with R
4
not be hydrogen. When that residue R
4
is hydrogen, the effects will not be attained. The polymers specified in EP 0 707 016 A1 and prepared with metallocenes, especially the polypropylene prepared with those metallocenes, however, have shown unsatisfactory characteristics in regard of the elastic behavior.
BRIEF SUMMARY OF THE INVENTION
It is the object of the present invention to find a new catalyst and a process for making polymers from olefinically unsaturated compounds, which have not only thermoplastic characteristics, but also thermoplastic-elastic characteristics, thus making the polymers useful for many applications.


REFERENCES:
patent: 5747621 (1998-05-01), Resconi et al.
patent: 5840947 (1998-11-01), Kuber et al.
patent: 28 30 160 (1979-01-01), None
patent: 197 09 486 (1998-09-01), None
patent: 0 582 194 (1994-02-01), None
patent: 0 707 016 (1996-04-01), None
patent: 0 747 406 (1996-12-01), None
patent: 2 241 244 (1991-08-01), None
patent: PCT/EP95/05016 (1996-07-01), None
patent: PCT/US98/22028 (1999-04-01), None
Dietrich et al., “New Class of Thermoplastic Elastic Polypropenes Prepared with a High Activity ‘Dual Side’ Zirconocene Catalyst,”RAPRA Abstracts, 36 (1) (Jan., 1999).
Dietrich et al., “Control of Stereoerror Formation with High-Activity ‘Dual-Side’ Zirconocene Catalysts: A Novel Strategy to Design the Properties of Thermoplastic Elastic Polypropenes,”J. Am. Chem. Soc., 121 (18), 4348-4355 (1999).
Rieger et al., “Novel Metallocene Catalyzed Polypropene Homo-and Brush-Copolymers: Control of New Morphologies and Beyond,”Polym. Mater. Sci. Eng., 80, 51-52 (1999).
Rieger, B. “Stereospecific Propene Polymerization with rac-[1,2-bis(&eegr;5-(9-fluorenyl))-1-phenylethane]zirconium dichloride/methylalumoxane,”Polymer Bulletin, 32 (1), 41-46 (Jan. 1994).
Search Report for Application No. DE 198 16 154 A1 dated Oct. 21, 1999.
Search Report for Application No. PCT/EP99/02378 dated Sep. 17, 1999.
Keii et al.Catalytic Defin Polymerization, Tokyo: Kodanska Elsevier Pub., pp. 439-480, (1990).

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