Details

Autor(en) / Beteiligte

• Qian, F
• Liu, K
• Ma, H

Titel

Polymerization of epsilon -Caprolactone and Copolymerization with rac-Lactide Catalyzed by Mono(amidinate) Aluminum Complexes

Ist Teil von

• Chinese journal of catalysis, 2011-01, Vol.32 (1), p.189-196

Erscheinungsjahr

2011

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Mono(amidinate) aluminum complexes showed high catalytic activity for the ring-opening polymerization of epsilon -caprolactone in toluene at ambient temperature. Monomer conversion up to 91% could be reached within 1 h when using [{PhC(N-2,6- super(i)Pr sub(2)C sub(6)H sub(3)) sub(2)}AlMe sub(2)] (C1) as initiator at 25 degree C. The electron-donating groups on the ortho-positions of the N-substituted phenyl ring were superior to the electron-withdrawing groups for the enhancement of the catalytic activity, but both brought an increase in activity when compared with the un-substituted complex C7. The complexes bearing two ortho-substituents on one of the N-phenyl rings were more active than the analogues bearing one orrto-substituent. Although high molecular weight poly( epsilon -caprolactone)s were obtained by using these aluminum catalysts, the polymerization of epsilon -caprolactone was not well controlled as indicated by the broad molecular weight distributions (PDI = 1.43-1.85) and the deviation of the n