1
John A Ewen, Abbas Razavi: Process and catalyst for producing syndiotactic polyolefins. Fina Technology, Stuart L Watt, John K Abokhair, M Norwood Cheairs, January 9, 1990: US04892851 (286 worldwide citation)

The invention provides a metallocene catalyst for use in preparing syndiotactic polyolefins. The catalyst comprises a bridged metallocene in which one of the cyclopentadienyl rings is substituted in a substantially different manner from the other ring. It was discovered that this type of catalyst is ...


2
Michael J Elder, Abbas Razavi, John A Ewen: Process and catalyst for producing syndiotactic polyolefins. Fina Technology, William D Jackson, Jim D Wheelington, October 13, 1992: US05155080 (134 worldwide citation)

Syndiospecific catalysts and processes for the syndiotactic propagation of a polymer chain derived from an ethylenically unsaturated monomer which contains 3 or more carbon atoms or is a substituted vinyl compound. The catalysts comprise an unbalanced metallocene cation, characterized by a cationic ...


3
Michael J Elder, Abbas Razavi, John A Ewen: Process and catalyst for producing syndiotactic polyolefins. Fina Technology, William D Jackson, Jim D Wheelington, M Norwood Cheairs, July 6, 1993: US05225500 (72 worldwide citation)

Syndiospecific catalysts and processes for the syndiotactic propagation of a polymer chain derived from an ethylenically unsaturated monomer which contains 3 or more carbon atoms or is a substituted vinyl compound. The catalysts comprise an unbalanced metallocene cation, characterized by a cationic ...


4
Guy Debras, Abbas Razavi, Jacques Michel: Production of multimodal polythylene. Fina Research, Gilbreth & Associates, February 12, 2002: US06346575 (55 worldwide citation)

A process for the preparation of polyethylene resins having a multimodal molecular weight distribution which comprises:


5
Abbas Razavi: Non-bridged syndiospecific metallocene catalysts and polymerization process. Fina Technology, William D Jackson, Jim D Wheelington, November 10, 1992: US05162278 (52 worldwide citation)

Syndiospecific catalysts and processes for the syndiotactic propagation of a polymer chain derived from an ethylenically unsaturated monomer which contains 3 or more carbon atoms or is substituted vinyl compound. The catalysts comprise unbalanced stereorigid metallocenes in which a structural bridge ...


6
Abbas Razavi, John A Ewen: Process for producing syndiotactic polyolefins. Fina Technology, Jim D Wheelington, John K Abokhair, M Norwood Cheairs, August 2, 1994: US05334677 (46 worldwide citation)

The invention provides a metallocene catalyst for use in preparing syndiotactic polyolefins. The catalyst comprises a bridged metallocene in which one of the cyclopentadienyl rings is substituted in a substantially different manner from the other ring. It was discovered that this type of catalyst is ...


7
Abbas Razavi, Guy L G Debras: Process for producing polyolefins and polyolefin catalyst. Fina Research, M Norwood Cheairs, Jim Wheelington, February 17, 1998: US05719241 (43 worldwide citation)

The present invention provides a process for preparing polyolefins having a multimodal or at least bimodal molecular weight distribution by contacting in a reaction mixture under polymerization conditions at least one olefin and a catalyst system comprising a supported catalyst-component comprising ...


8
John A Ewen, Abbas Razavi: Syndiotactic polypropylene. Fina Technology, Jim D Wheelington, M Norwood Cheairs, December 19, 1995: US05476914 (42 worldwide citation)

The invention provides for highly crystalline syndiotactic polypropylene comprising a high percentage of racemic (r) dyads. The high crystallinity may be due to the polymerization mechanism of metallocene catalysts of a particular structure which appear to produce syndiotactic polypropylene of a new ...


9
Abbas Razavi, John A Ewen: Syndiotactic polypropylene. Fina Technology, Jim D Wheelington, February 6, 2001: US06184326 (39 worldwide citation)

The invention provides for highly crystalline syndiotactic polypropylene comprising a high percentage of racemic (r) dyads. The high crystallinity may be due to the polymerization mechanism of metallocene catalysts of a particular structure which appear to produce syndiotactic polypropylene of a new ...


10
Abbas Razavi: Polyolefin production. Fina Research, Hitt Gaines & Boisbrun, February 4, 2003: US06515086 (39 worldwide citation)

A process for preparing polyolefins having a monomer length of up to C10, which comprises first contacting: (1) a metallocene catalyst component for the preparation of a polyolefin which comprises an isotactic polyolefin or syndiotactic/isotactic block polyolefin having a monomer length of up to C