SEQUENCE DISTRIBUTION OF MONOMER UNITS IN BUTADIENE-ISOPRENE COPOLYMER PREPARED WITH LANTHANIDE CATALYSTS
稀土催化丁二烯-异戊二烯共聚物的序列分布

Monomer sequence distribution of copolymers of butadiene and isoprene prepared with lanthanide complexes LaCl2-C2H5OH-Al(C2H5)2 was determined by 13C-NMR spec-trometry.The dyad distribution and number-average sequence length of these copolymers were quantitatively determined. The results show that sequence distribution of monomer units in copolymers prepared with Nd, Pr and Ce catalysts follow Bernoullian statistical model, while copolymers prepared with Y, Sm, Dy and Gd catalysts show some deviation from it.