Polymerization of acrylonitrile catalyzed by lanthanide-sodium alkoxide clusters Ln_2(OCH_2CH_2NMe_2)_(12)(OH)_2Na_8 Ln=Yb (1),Nd (2) and Sm (3)

摘要

Polymerization of acrylonitrile was carried out using,for the first time,the lanthanide-sodium alkoxide clusters Ln2(OCH2CH2NMe2)12(OH)2Na8 [Ln=Yb (1),Nd (2) and Sm (3)] as single component catalysts.These heterobimetallic complexes exhibit high activity and give atactic polyacrylonitriles with high molecular weight.The polymerization temperature can be varied over the range ?78 to 50°C.The solvent has a substantial effect on the polymerization activity.The order of activity for solvents is DMF>DME≈toluene≈THF>hexane.