Polymerization of acrylonitrile catalyzed by lanthanide-sodium alkoxide clusters Ln_2(OCH_2CH_2NMe_2

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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. 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.
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