Preparation Method Of Catalyst For Ethylene Polymerization
Disclosed is a method for preparing a solid catalyst capable of controlling a molecular weight distribution and polydispersity according to an organic compound as used in a polymerization reaction, in which the solid catalyst contains titanium tetrachloride and a diester or diether organic compound. The catalyst having excellent polymerization activity, and allowing uniform particle size and high apparent density of the ultra-high molecular weight polyethylene, and easily controlling the molecular weight distribution and polydispersity of the ultra-high molecular weight polyethylene may be prepared simply and efficiently.
1 . A preparation method of a catalyst for producing ultra-high molecular weight polyethylene, the method comprising:
(1) reacting magnesium dichloride (MgCl 2 ) with alcohol to prepare a magnesium compound solution;
(2) reacting titanium tetrachloride with the magnesium compound solution prepared in the step (1) to prepare a precursor; and
(3) reacting the precursor with the titanium tetrachloride to form a first reacted precursor, and then secondarily reacting the first reacted precursor with a diether compound represented by a following general formula (I) or a diester compound represented by a following general formula (II) or a mixture of the diether compound and the diester compound to prepare the catalyst:
R 1 OCR 2 COR 3 (I)
R 1 OOCR 2 COOR 3 (II)
where each of R 1 and R 3 represents a linear or branched alkyl group having 1 to 10 carbon atoms, and R 2 represents a linear or branched alkyl group having 1 to 20 carbon atoms.
2 . The method of claim 1 , wherein the alcohol is a primary alcohol having 2 to 10 carbon atoms.