T. Uozumi et al., Synthesis of ethylene-a-olefin alternating copolymers with Et(1-Ind)(9-Flu)ZrCl2-MAO catalyst system, MACRO CH P, 201(14), 2000, pp. 1748-1752
Full Paper: Copolymerizations of ethylene and alpha-olefins (4-methyl-1-pen
tene, 1-hexane, 1-decane and 1-hexadene) were carried out with Et(1-Ind)(9-
Flu)ZrCl2-MAO as the catalyst system. The degree of alternation in the resu
lting copolymers is higher than 92.1% for all the copolymers and close to 1
00% for ethylene-1-decene copolymer. Copolymerization behaviours focusing i
n the misinsertions during the polymerizations are investigated in detail f
rom dyad and triad distributions estimated by C-13 NMR analysis of copolyme
rs. A reactivity ratio, r(E)(B), was obtained for ethylene-1-hexane copolym
ers using a simplified two sites alternating mechanism and found to be 8.7,
which is the same order of that reported in ethylene-propene copolymerizat
ions with Me2C(3-RCp)(Flu)-ZrCl2-MAO as the catalyst system.