| 摘要 |
A solid catalyst, for ethylene (co)polymerisation consists of (1) a Si02 support in particle form (50-90 wt. %) and (2) an active part (50-10 wt. %) contg. Ti, Mg, Cl and alkoxy gps. Prepn. of the catalyst comprises (a) prepn. of MgCl2 soln. in C2H5OH, (b) impregnation of Si02 particles by suspension in the soln. (c) elimination of unabsorbed C2H5OH by evapn. at up to 60 deg.C (no higher) and recovering a particulate solid contg. C2H5OH and MgCl2 in a molar ratio of 5/1-6/1, (d) heating the solid to up to 150 deg.C (no higher) and partially eliminating the absorbed C2H5OH by evapn. to a molar ratio of C2H5OH to MgCl2 of 1.5/1-4/1, (e) interacting the solid with titanium chlorides, alkoxy and chloroalkoxides to an atomic ratio of Mg to Ti or 0.5/1-8/1, (f) possibly interacting the solid from (e) with an alkylaluminium chloride to an atomic ratio of (c) to Ti of 10/1-16/1, and (g) recovering the catalyst. Also claimed is a catalyst formed from the described catalyst and an aluminium organometallic cpd. (co-catalyst) selected from aluminium trialkyls and alkylaluminium halides (chlorides) contg. 1-5C (pref.2-4C) alkyl, with an atomic ratio of Al (in the co-catalyst) to Ti (in the solid catalyst) of 20:1-200:1 (pref. 50:1-15:1). |
