Supported, titanized chromium catalyst and its use for preparing homopolymers and copolymers of ethylene

Abstract

Novel supported, titanized chromium catalysts for the homopolymerization of ethylene and the copolymerization of ethylene with α-olefins, a process for preparing them and to their use for the polymerization of olefins.

1 - 11 . (canceled) 
     
     
         12 . A homopolymer of ethylene or a copolymer of ethylene with α-olefins obtained by a process comprising polymerizing ethylene or mixtures of ethylene and α-olefins in the presence of at least one supported, titanized chromium catalyst obtained by a process comprising:
 A) bringing a spherical, spray-dried, oxidic support material into contact with a titanium compound in a suspension,   B) bringing the support material which has been treated in this way into contact with a chromium salt solution in a suspension and subsequently removing the solvent,   C) if desired, calcining the precatalyst obtained in step B) at above 280° C. in an inert gas atmosphere and subsequently   D) activating the precatalyst obtained in step B) or C) at from 500° C. to 800° C. in an oxygen-containing atmosphere.   
     
     
         13 . A homopolymer or copolymer of ethylene with α-olefins obtained by a process comprising polymerizing ethylene or mixtures of ethylene and α-olefins in the presence of at least one supported, titanized chromium catalyst obtained by a process comprising:
 A) bringing a spherical, spray-dried, oxidic support material into contact with a titanium compound in a suspension,   B) bringing the support material which has been treated in this way into contact with a chromium salt solution in a suspension and subsequently removing the solvent,   C) if desired, calcining the precatalyst obtained in step B) at above 280° C. in an inert gas atmosphere and subsequently   D) activating the precatalys obtained in step B) or C) at from 500° C. to 800° C. in an oxygen-containing atmosphere,   
       wherein said homopolymer or copolymer has an HLMI of from 1 to 50 g/10 min, an MFI (190° C./2.16 kg) of from 0 to 10 g/10 min, a density of from 0.9 to 0.97 g/cm 3  and a molar mass distribution M w /M n  in the range from 3 to 50. 
     
     
         14 . A method for the production of films comprising utilizing a homopolymer or copolymer of ethylene as claimed in  claim 12 . 
     
     
         15 . A film comprising a homopolymer or copolymer of ethylene as claimed in  claim 12 . 
     
     
         16 . A process for the production of films, said process comprising extruding in blown film production the homopolymer or copolymer of  claim 12 . 
     
     
         17 . The homopolymer or copolymer of ethylene of  claim 12 , wherein the polymerization is carried out in the presence of a supported, titanized chromium catalyst and a supported, nontitanized chromium catalyst which can be prepared by a process in which a spherical, spray-dried support material is treated as described in steps B) to D). 
     
     
         18 . The homopolymer or copolymer of ethylene of  claim 12 , wherein the polymerization is carried out in the gas phase. 
     
     
         19 . A method for the production of films comprising utilizing a homopolymer or copolymer of ethylene as claimed in  claim 13 . 
     
     
         20 . A film comprising the homopolymer or copolymer of ethylene of  claim 13 . 
     
     
         21 . A process for the production of films, said process comprising extruding in blown film production the homopolymer or copolymer of  claim 13 . 
     
     
         22 . The homopolymer or copolymer of ethylene of  claim 13 , wherein the polymerization is carried out in the presence of a supported, titanized chromium catalyst and a supported, nontitanized chromium catalyst which can be prepared by a process in which a spherical, spray-dried support material is treated as described in steps B) to D). 
     
     
         23 . The homopolymer or copolymer of ethylene of  claim 13 , wherein the polymerization is carried out in the gas phase.