Xufeng Ni, Weiwei Zhu and Prof. Dr. Zhiquan Shen
Polymerization of n-octylallene was successfully carried out using a conventional binary rare earth catalytic system composed of rare earth tris(2- ethylhexylphosphonate) (Ln(P204)3) and tri-isobutyl aluminum (Al(i-Bu)3) for the first time. The effects of catalyst, solvent, reaction time and temperature on the polymerization of n-octylallene were studied. The resulting poly(n- octylallene) has weight-average molecular weight of 11000, molecular weight distribution of 1.4 and 96% yield under the moderate reaction conditions: [Al]/[Y] =50 (molar ratio), [n-octylallene]/[Y] =100 (molar ratio), polymerized at 80°C for 20 h in bulk. The poly(n-octylallene) obtained consisted of 1,2- and 2,3-polymerized units, and was characterized by FT-IR, 1H NMR and GPC. Further investigation shows that the polymerization of n-octylallene has some living polymerization characteristics, preparing the polymer with controlled molecular weight and narrower molecular weight distribution.