Novel High Clarity Low Haze Compositions

Abstract

A first embodiment which is a bimodal polymer having a weight fraction of a lower molecular weight (LMW) component ranging from about 0.25 to about 0.45, a weight fraction of a higher molecular weight (HMW) component ranging from about 0.55 to about 0.75 and a density of from about 0.931 g/cc to about 0.955 g/cc which when tested in accordance with ASTM D1003 using a 1 mil test specimen displays a haze characterized by equation: % Haze=2145−2216*Fraction LMW −181*a molecular weight distribution of the LMW component (MWD LMW )−932*a molecular weight distribution of the HMW component (MWD HMW )+27*(Fraction LMW *MWD LMW )+1019*(Fraction LMW *MWD HMW )+73*(MWD LMW *MWD HMW ) wherein fraction refers to the weight fraction of the component in the polymer as a whole.

What is claimed is: 
     
         1 . A metallocene catalyst compound having a formula:
   (X 1 R 1 )(X 2 R 2   2 )(X 3 )(X 4 )M 1 ,   wherein:
 (X 1 ) is cyclopentadienyl, indenyl, or fluorenyl; 
 (X 2 ) is fluorenyl; 
 (X 3 ) and (X 4 ) are independently an aliphatic group, an aromatic group, a cyclic group, a combination of aliphatic and cyclic groups, a substituted derivative of an aliphatic group, a substituted derivative of an aromatic group, a substituted derivative of a cyclic group, a substituted derivative of a combination of aliphatic and cyclic groups, an unsaturated aliphatic group having from 1 to about 20 carbon atoms, or a halide; 
 R 1  is H or an unsaturated aliphatic group having from 3 to about 10 carbon atoms; 
 R 2  is H, an alkyl group having from 1 to about 12 carbon atoms, or an aryl group; and 
 M 1  is Zr or Hf; 
   wherein (X 1 ) and (X 2 ) are connected by a disubstituted bridging group comprising a first substituent which is an aromatic group or an unsaturated aliphatic group having from 1 to about 20 carbon atoms, and a second substituent which is an aromatic group or an unsaturated aliphatic group having from 1 to about 20 carbon atoms.   
     
     
         2 . The metallocene catalyst compound of  claim 1 , wherein the first substituent is a phenyl group. 
     
     
         3 . The metallocene catalyst compound of  claim 1 , wherein the second substituent is a phenyl group, an alkyl group, a butenyl group, a pentenyl group, or a hexenyl group. 
     
     
         4 . The metallocene catalyst compound of  claim 1 , wherein the second substituent is an unsaturated aliphatic group having from 3 to about 10 carbon atoms. 
     
     
         5 . The metallocene catalyst compound of  claim 1 , wherein the disubstituted bridging group further comprises one atom bonded to both (X 1 ) and (X 2 ). 
     
     
         6 . The metallocene catalyst compound of  claim 5 , wherein the one atom is carbon or silicon. 
     
     
         7 . A polymerization catalyst composition comprising:
 a first metallocene compound having a formula:
   (X 1 R 1 )(X 2 R 2   2 )(X 3 )(X 4 )M 1 , 
 wherein:
 (X 1 ) is cyclopentadienyl, indenyl, or fluorenyl; 
 (X 2 ) is fluorenyl; 
 (X 3 ) and (X 4 ) are independently an aliphatic group, an aromatic group, a cyclic group, a combination of aliphatic and cyclic groups, a substituted derivative of an aliphatic group, a substituted derivative of an aromatic group, a substituted derivative of a cyclic group, a substituted derivative of a combination of aliphatic and cyclic groups, an unsaturated aliphatic group having from 1 to about 20 carbon atoms, or a halide; 
 R 1  is H or an unsaturated aliphatic group having from 3 to about 10 carbon atoms; 
 R 2  is H, an alkyl group having from 1 to about 12 carbon atoms, or an aryl group; and 
 M 1  is Zr or Hf; 
 wherein (X 1 ) and (X 2 ) are connected by a disubstituted bridging group comprising a first substituent which is an aromatic group or an unsaturated aliphatic group having from 1 to about 20 carbon atoms, and a second substituent which is an aromatic group or an unsaturated aliphatic group having from 1 to about 20 carbon atoms; and 
 
   a second metallocene compound.   
     
     
         8 . The polymerization catalyst composition of  claim 7 , wherein the first substituent is a phenyl group. 
     
     
         9 . The polymerization catalyst composition of  claim 7 , wherein the second substituent is a phenyl group, an alkyl group, a butenyl group, a pentenyl group, or a hexenyl group. 
     
     
         10 . The polymerization catalyst composition of  claim 7 , wherein the second substituent is an unsaturated aliphatic group having from 3 to about 10 carbon atoms. 
     
     
         11 . The polymerization catalyst composition of  claim 7 , wherein the disubstituted bridging group of the first metallocene compound further comprises one atom bonded to both (X 1 ) and (X 2 ). 
     
     
         12 . The polymerization catalyst composition of  claim 11 , wherein the one atom is carbon or silicon. 
     
     
         13 . The polymerization catalyst composition of  claim 7 , the second metallocene compound having a formula:
   (X 5 )(X 6 )(X 7 )(X 8 )M 2 ,   wherein:
 (X 5 ) and (X 6 ) are independently cyclopentadienyl, indenyl, substituted cyclopentadienyl, or substituted indenyl; 
 (X 7 ) and (X 8 ) are independently an aliphatic group, an aromatic group, a cyclic group, a combination of aliphatic and cyclic groups, a substituted derivative of an aliphatic group, a substituted derivative of an aromatic group, a substituted derivative of a cyclic group, a substituted derivative of a combination of aliphatic and cyclic groups, an unsaturated aliphatic group having from 1 to about 20 carbon atoms, or a halide; and 
 M 2  is Zr or Hf. 
   
     
     
         14 . The polymerization catalyst composition of  claim 13 , wherein each substituent on (X 5 ) and (X 6 ) is independently selected from a linear or branched alkyl group, or a linear or branched alkenyl group. 
     
     
         15 . The polymerization catalyst composition of  claim 14 , wherein the alkyl group or the alkenyl group is unsubstituted or substituted. 
     
     
         16 . The polymerization catalyst composition of  claim 13 , wherein any substituent on (X 5 ) and (X 6 ) has from 1 to about 20 carbon atoms. 
     
     
         17 . The polymerization catalyst composition of  claim 7 , wherein the ratio of the first metallocene compound to the second metallocene compound is from about 1:10 to about 10:1. 
     
     
         18 . The polymerization catalyst composition of  claim 7 , further comprising an activator. 
     
     
         19 . The polymerization catalyst composition of  claim 18 , wherein the activator is a solid oxide activator-support, a chemically treated solid oxide, a clay mineral, a pillared clay, an exfoliated clay, an exfoliated clay gelled into another oxide matrix, a layered silicate mineral, a non-layered silicate mineral, a layered aluminosilicate mineral, a non-layered aluminosilicate mineral, an aluminoxane, a supported aluminoxane, an ionizing ionic compound, an organoboron compound, or any combination thereof. 
     
     
         20 . The polymerization catalyst composition of  claim 7 , further comprising an organoaluminum compound.