Producing polyolefin products

Abstract

Catalyst systems and methods for making and using the same. A method of polymerizing olefins to produce a polyolefin polymer with a multimodal composition distribution, includes contacting ethylene and a comonomer with a catalyst system. The catalyst system includes a first catalyst compound and a second catalyst compound that are co-supported to form a commonly supported catalyst system. The first catalyst compound includes a compound with the general formula (C5HaR1b)(C5HcR2d)HfX2. The second catalyst compound comprises the following formula:wherein each R3 or R4 is independently H, a hydrocarbyl group, a substituted hydrocarbyl group, or a heteroatom group, wherein each R3 or R4 may be the same or different, and each X is independently a leaving group selected from a labile hydrocarbyl, a substituted hydrocarbyl, a heteroatom group, or a divalent radical that links to an R3 group.

1 . A method of controlling a molecular weight distribution of a polyolefin polymer generated in a polymerization reactor, comprising:
 contacting ethylene and a comonomer with a catalyst system in the polymerization reactor, wherein the catalyst system comprises a first catalyst compound and a second catalyst compound that are co-supported to form a commonly supported catalyst system, wherein the first catalyst compound comprises the following formula:
   (C 5 H a R 1   b )(C 5 H c R 2   d )HfX 2    
   
       wherein each R 1  is independently H, a hydrocarbyl group, a substituted hydrocarbyl group, or a heteroatom group; each R 2  is independently H, a hydrocarbyl group, a substituted hydrocarbyl group, or a heteroatom group; a and c are ≥3; a+b=c+d=5; at least one R 1  and at least one R 2  is a hydrocarbyl or substituted hydrocarbyl group; adjacent R 1  and R 2  groups may be coupled to form a ring; and each X is independently a leaving group selected from a labile hydrocarbyl, substituted hydrocarbyl, or heteroatom group, or a divalent radical that links to an R 1 , or R 2  group; and the second catalyst compound comprises the following formula: 
       
         
           
           
               
               
           
         
       
       wherein each R 3  or R 4  is independently H, a hydrocarbyl group, a substituted hydrocarbyl group, or a heteroatom group, wherein each R 3  or R 4  are optionally the same or different; and each X is independently a leaving group selected from a labile hydrocarbyl, a substituted hydrocarbyl, a heteroatom group, or a divalent radical that links to an R 3  group; and
 combining a trim catalyst solution with the catalyst system prior to entering the polymerization reactor, wherein the trim catalyst solution includes an additional amount of the second catalyst in a non-reactive hydrocarbon and wherein the additional amount of the second catalyst in the trim catalyst solution controls the molecular weight distribution of the polyolefin polymer generated in the polymerization reactor. 
 
     
     
         2 . The method of  claim 1 , wherein a value of a comonomer/ethylene incorporation ratio for the second catalyst is less than about 0.8 as large as comonomer/ethylene incorporation ratio of the first catalyst. 
     
     
         3 . The method of  claim 1 , wherein a value of the comonomer/ethylene incorporation ratio for the second catalyst is less than about 0.25 as large as a comonomer/ethylene incorporation ratio of the first catalyst. 
     
     
         4 .- 14 . (canceled) 
     
     
         15 . The method of  claim 1 , comprising adjusting a ratio of the comonomer to ethylene within the polymerization reactor to control a composition distribution, the molecular weight distribution, a melt index (I 2 ), or a ratio of two melt indices, or any combinations thereof, of the polyolefin polymer. 
     
     
         16 . The method of  claim 1 , comprising adjusting a ratio of the hydrogen to ethylene within the polymerization reactor to control a composition distribution, the molecular weight distribution, a melt index (I 2 ), or a ratio of two melt indices, or any combinations thereof, of the polyolefin polymer. 
     
     
         17 .- 43 . (canceled) 
     
     
         44 . The method of  claim 1 , wherein combining the trim catalyst solution with the catalyst system occurs enroute to the polymerization reactor. 
     
     
         45 . The method of  claim 44 , wherein combining the trim catalyst solution with the catalyst system enroute to the polymerization reactor occurs in an in-line mixer immediately prior to entering the polymerization reactor. 
     
     
         46 . The method of  claim 1 , wherein the non-reactive hydrocarbon is selected from the group consisting of an alkane solvent, an aromatic solvent, mineral oil and combinations thereof. 
     
     
         47 . The method of  claim 1  wherein the second catalyst compound is predominantly meso in structure. 
     
     
         48 . The method of  claim 1 , wherein the second catalyst compound comprises at least one compound with the following formula: 
       
         
           
           
               
               
           
         
       
     
     
         49 . The method of  claim 1 , wherein the second catalyst compound comprises at least one compound with the following formula: 
       
         
           
           
               
               
           
         
       
     
     
         50 . The method of  claim 1 , wherein the molar ratio of the first catalyst compound to the second catalyst compound is 10:1 to 1:10. 
     
     
         51 . The method of  claim 1 , wherein the molar ratio of the first catalyst compound to the second catalyst compound is 3:1 to 1:3. 
     
     
         52 . The method of  claim 1 , wherein the trim catalyst solution includes an activator selected from the group consisting of an aluminoxane, a modified aluminoxane, an alkylaluminum and combinations thereof. 
     
     
         53 . The method of  claim 52 , wherein the trim catalyst solution has a ratio of metal from the activator to metal from the additional amount of the second catalyst of 1000:1 to 0.5:1.