Polymerization of α-pinene using Lewis acidic ionic liquid as catalyst for production of terpene resin

摘要

The polymerization of a-pinene was investigated in the presence of Lewis acidic ionic liquids (ILs). The results indicated that ILs 1-(1-ethyl acetate-yl)-3-methylimidazolium chloroaluminates ([EtOCOCH_2-mim]Cl-AlCl_3), especially molar fraction of AlCl_3 x = 0.67, had excellent catalytic performance for the polymerization of a-pinene. The yield and softening point of solid resin reached to 52.0% and 115 ℃, respectively, when the polymerization was carried out at -5 ℃ for 4 h. IL was reused for five times without a decrease in the catalytic performance. Compared with the traditional catalyst AlCl_3, IL exhibited some advantages such as simplicity and efficiency of the product isolation, higher yield and softening point of the product, and excellent reusability.