Olefin polymerization catalyst and process for preparing polyolefins with said catalyst

Abstract

An olefin polymerization catalyst is described which includes: (A) a solid catalyst component being prepared by copulverizing a magnesium compound, an aluminum compound, an electron donor and a titanium compound, and (B) an organoaluminum compound. The present invention is also directed to a process for preparing polyolefins using the aforesaid catalyst system to polymerize olefins.

What is claimed is:  
     
         1 . An olefin polymerization catalyst, comprising: 
 (A) a solid catalyst component being prepared by copulverizing a magnesium compound, an aluminum compound, an electron donor from organic compounds which contain at least one atom selected from oxygen, silicon, nitrogen, sulfur and phosphorus atoms, and a titanium compound; and    (B) an organoaluminum compound.    
     
     
         2 . A catalyst according to  claim 1  wherein said magnesium compound is represented by the general formula Mg(OR) 2-n X n  wherein R is an alkyl radical containing up to 12 carbon atoms, 0≦n≦2 and X is a halogen atom.  
     
     
         3 . A catalyst according to  claim 2  wherein said magnesium compound is selected from the group consisting of magnesium dichloride, magnesium dibromide, magnesium difluoride, magnesium diiodide, magnesium ethoxychloride, magnesium ethoxide and magnesium isopropoxide.  
     
     
         4 . A catalyst according to  claim 3  wherein said magnesium compound is magnesium dichloride.  
     
     
         5 . A catalyst according to  claim 1  wherein said aluminum compound is represented by the general formula Al(OR′) 3-m X m  wherein R′ is an alkyl radical containing up to 12 carbon atoms or an aryl group, 0≦m≦3 and X is a halogen atom.  
     
     
         6 . A catalyst according to  claim 5  wherein said aluminum compound is selected from the group consisting of aluminum trimethoxide, aluminum triethoxide, aluminum tri-n-propoxide, aluminum triisopropoxide, aluminum tri-n-butoxide, aluminum tri-sec-butoxide, aluminum tri-t-butoxide, ethoxyaluminum dichloride, diethoxyaluminum chloride, aluminum trichloride and aluminum phenoxide.  
     
     
         7 . The catalyst according to  claim 6  wherein said aluminim compound is selected from the group consisting of aluminum triethoxide and aluminum trimethoxide.  
     
     
         8 . A catalyst according to  claim 1  wherein said electron donor is selected from the goups consisting of ethers, alcohols esters, ketones, silanes, amines, acyl halides, phosphines, and phosphine amides.  
     
     
         9 . A catalyst according to  claim 8  wherein said esters are saturated or unsaturated eaters represented by the formula R 1 COOR 2  wherein R 1  and R 2  each is alkyl, alkenyl, aralkyl, cycloalkyl or aryl, or those substituted with halogen, or cyclic esters.  
     
     
         10 . A catalyst according to  claim 9  wherein said esters are selected from the group consisting of butyl formate, ethyl acetate, butyl acetate, ethyl acrylate, ethyl butyrate, isobutyl isobutyrate, methyl methacrylate, diethyl maleate, diethyl tartrate, ethyl cyclohexanecarbonate, ethyl benzoate, ethyl p-methoxybenoate, methyl p-methylbenzoate, ethyl p-tertbutylbenzoate, dialkyl phthalate, dially phthalate, and ethyl alpha-naphthoate.  
     
     
         11 . A catalyst according to  claim 8  wherein silanes are selected from the group consisting of tetrahydrocarbylsilanes and their halogen or alkoxy derivatives, linear or cyclic organopolysilanes, siloxane polymers, and other silicon-containing organic compounds.  
     
     
         12 . A catalyst according to  claim 11  wherein said silanes are selected from the group consisting of tetramethylsilane, trimethylphenylsilane, diethyldichlorosilane, phenyltrichlorosilane, diphenyldichlorsilane, trimethoxymethylsilane, diphenyldimethoxysilane, dimethyldiethoxysilane, diethyldiethoxysilane, triphenylethoxysilane, hexaphenyldisilane, dimethypolysiloxane, diphenylpolysiloxane, and 2(trimethoxysilyethyl)pyridine.  
     
     
         13 . A catalyst according to  claim 1  wherein said titanium compound is represented by the formula Ti(OR″) 4-p X p  wherein R″ is an alkyl radical containing up to 12 carbon atoms, 0≦p≦4 and X is a halogen atom.  
     
     
         14 . A catalyst according to  claim 15  wherein said titanium compound is selected from the group consisting of titanium tetrachloride, titanium tetraethoxide, diethoxytitanium dichloride, titanium tetrabutoxide, and ethoxytitanium trichloride.  
     
     
         15 . A catalyst according to  claim 1  wherein said catalyst components have ratios of: the mole ratio of the aluminum compound to the magnesium compound from 0.005:1 to 1:1, the mole ratio of the electron donor to the magnesium compound from 0.005:1 to 1:1, and the amount of titanium in the resulting solid from 0.5 to 10% by weight.  
     
     
         16 . A catalyst according to  claim 1  wherein said organoaluminum compound is represented by the formula AlR′″ q Y 3-q  wherein R′″ represents hydrogen or an alkyl radical containing up to 12 carbon atoms, Y represents a halogen or an alkoxy group having from about 1 to 12 carbon atoms and q is in a range of 1≦q≦3.  
     
     
         17 . A catalyst according to  claim 16  wherein said organoaluminum compound is selected from the group consisting of triethylaluminum, tri-n-propylaluminum, tri-iso-butylaluminum, tri-n-octylaluminum, tri(2-methylpentyl) aluminum, di-iso-butylaluminum hydride, ethylaluminum sesquichloride, diethylaluminum chloride, ethylaluminum dichloride, diethylaluminum ethoxide, diethylaluminum iodide, methylaluminoxane, and ethylaluminoxane, and among them trithylaluminum is particularly preferable.  
     
     
         18 . A catalyst according to  claim 1  wherein the molar ratio of the organoaluminum compound to the metal titanium in the solid catalyst component A may range 1000:1 to 0.5:1.  
     
     
         19 . A process for polymerization of olefins selected from the group consisting of ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-methyl 1-pentene, 4-methyl-1-heptene, 5-methyl-1-heptene, 6-methyl-1-heptene, and 4,4-dimenthyl-1-hexene, which comprises: reacting at least one of said olefins at elevated temperature in the presence of a catalyst, said catalyst being 
 (A) a solid catalyst component being prepared by copulverizing a magnesium compound, an aluminum compound, an electron donor selected from organic compounds which contain at least one atom selected from oxygen, silicon, nitrogen, sulfur and phosphorus atoms, and a titanium compound; and    (B) an organoaluminum compound.    
     
     
         20 . A process according to  claim 19  wherein said polymerization is conducted at a temperature in a range from 20° C. to 300° C. and a pressure in a range of 1 to 80 bar.