| 摘要 |
A process for the preparation by ethylene polymerization of at least one dialkyl magnesium compound of formula R—(CH2—CH2)n—Mg—(CH2—CH2)m—R′ in which R and R′, identical or different, represent aryl, benzyl, allyl or alkyl groups and in which the integers n and m, identical or different, represent average —CH2—CH2— chain formation numbers greater than 1, the process including a single stage of mixing the following components: at least one ligand or one ligand precursor, at least one rare earth salt, at least one dialkyl magnesium compound of formula R—Mg—R′, and ethylene, in a medium allowing contact between the components of the above mixture. |
| 主权项 |
1. Process for the preparation by ethylene polymerization of at least one dialkyl magnesium compound of formula R—(CH2—CH2)n—Mg—(CH2—CH2)m—R′ in which R and R′, identical or different, represent cyclic or non-cyclic, substituted or unsubstituted, linear or branched aryl, benzyl, allyl or alkyl groups, comprising from 1 to 20 carbon atoms and in which the integers n and m, identical or different, represent average —CH2—CH2— chain formation numbers greater than 1, in particular from 20 to 200,said process comprising a single stage of mixing the following components:
at least one ligand or one ligand precursor, at least one rare earth salt of formula MX3 in which M represents the rare earth element in the cationic form chosen from scandium, yttrium or the lanthanides and X the anion which is associated therewith, at least one dialkyl magnesium compound of formula R—Mg—R′ in which R and R′, identical or different, represent cyclic or non-cyclic, substituted or unsubstituted, linear or branched aryl, benzyl, allyl or alkyl groups, comprising from 1 to 20 carbon atoms, and ethylene,in a medium allowing contact between the components of the above mixture,said contact allowing the formation of a catalyst between M, the magnesium and the ligand or the ligand precursor,said medium being compatible with ethylene polymerization, which leads to a polymerization product or mixture of products of formula R—(CH2—CH2)n—Mg—(CH2—CH2)m—R′ in which R, R′, n and m have the meanings given above. |
