US 7,321,015 B2
Adjusting polymer characteristics through process control
Peter Phung Minh Hoang, Calgary (Canada); Cliff Robert Baar, Calgary (Canada); Victoria Ker, Calgary (Canada); Peter Zoricak, Calgary (Canada); and Paul Mesquita, Calgary (Canada)
Assigned to Nova Chemicals (International) S.A., (Switzerland)
Filed on Dec. 07, 2004, as Appl. No. 11/6,075.
Prior Publication US 2006/0122342 A1, Jun. 08, 2006
Int. Cl. C08F 4/64 (2006.01); C08F 2/34 (2006.01); C08F 2/38 (2006.01)
U.S. Cl. 526—73  [526/113; 526/114; 526/118; 526/119; 526/901; 526/905] 18 Claims
 
1. A process for controlling one or more of the ratio of high molecular weight polymer to low molecular weight polymer and the comonomer distribution in a continuous fluidized bed gas phase polymerization at a temperature from 50 to 120° C. of a reaction mixture comprising one or more of hydrogen, C1-7 non polymerizable hydrocarbons, and C2-8 olefins polymerized in the presence of a dual catalyst wherein both catalyst components are on the same support:
(i) the first component of which comprises a catalyst of the formula:

OG Complex Work Unit Drawing
wherein M is Zr; R1 and R6 are independently selected from the group consisting of C1-6 alkyl and C6-10 aryl radicals; R2 and R7 are independently selected from the group consisting of C 3-5 secondary and tertiary alkyl radicals; R3, R4, R5, R8, R9 and R10 are independently selected from the group consisting of a hydrogen atom, C1-4 alkyl radicals, C6-10 aryl radicals, C1-C4 alkoxy radicals which substituents have a Hammett σσρρ value of less than 0.2; and X and X′ are selected from the group consisting of a halogen atom, C1-4 alkyl radicals, C7-12 arylalkyl radicals, C6-10 phenoxy radicals, amido radicals which may be substituted by up to two C1-4 alkyl radicals and C1-4 alkoxy radicals; and
(ii) the second component of which comprises a catalyst of the formula:

OG Complex Work Unit Drawing
wherein M is a group 4 metal; Pl is a phosphinimine ligand; L is a monoanionic ligand selected from the group consisting of a cyclopentadienyl-type ligand; Y is an activatable ligand; m is 1 or 2; n is 0 or 1; and p is an integer and the sum of m+n+p equals the valence state of M;and an activator,which comprises one or more steps selected from the group consisting of:
(a) altering the temperature of the reaction by at least 2° C. within the range from 50 to 120° C.;
(b) altering the partial pressure of the hydrogen component of the reaction mixture by at least 0.02 psi;
(c) altering the partial pressure of ethylene in the reaction mixture by not less than 20 psi; and
(d) altering the amount of non polymerizable hydrocarbon in the reaction mixture by not less than 0.5 mole %.