| 摘要 |
The invention concerns the use of zinc derivatives of general formula (I) wherein: L<SUB>1 </SUB>represents a group of formula: -E<SUB>14</SUB>(R<SUB>14</SUB>)(R'<SUB>14</SUB>)(R''<SUB>14</SUB>), -E<SUB>15</SUB>(R<SUB>15</SUB>) (R'<SUB>15</SUB>) or -E<SUB>16</SUB>(R<SUB>16</SUB>); E is an atom of group 15; L<SUB>2 </SUB>and L<SUB>3 </SUB>independently represent a group of formula: -E<SUB>14</SUB>(R<SUB>14</SUB>)(R'<SUB>14</SUB>)(R''<SUB>14</SUB>), -E<SUB>15</SUB>(R<SUB>15</SUB>)(R'<SUB>15</SUB>) or -E<SUB>16</SUB>(R<SUB>16</SUB>), or together form a chain of formula -L'<SUB>2</SUB>-A-L'<SUB>3</SUB>-; A represents a saturated or unsaturated chain comprising one, two or three elements of group 14; L'<SUB>2 </SUB>and L'<SUB>3 </SUB>independently represent a group of formula -E<SUB>14</SUB>(R<SUB>14</SUB>)(R'<SUB>14</SUB>) -E<SUB>15</SUB>(R<SUB>15</SUB>) or -E<SUB>16</SUB>-; E<SUB>14 </SUB>is an element of group 14; E<SUB>15 </SUB>is an element of group 15; E<SUB>16 </SUB>is an element of group 16; R<SUB>14</SUB>, R'<SUB>14</SUB>, R''<SUB>14</SUB>, R<SUB>15</SUB>, R'<SUB>15 </SUB>and R<SUB>16 </SUB>represent various groups, as (co) polymerisation catalysts of cyclic esters |
