writer：XL Zhu, G Wu, ZC Qiu, Y Zhou, J Gong, KK Yang, YZ Wang
keywords：kinetics (polym.)，lanthanum isopropoxide，polyesters，thermodynamics，1,4-dioxan-2-one
source：期刊
specific source：Journal of Polymer Science Part A: Polymer Chemistry
Issue time：2008年
Lanthanum isopropoxide (La(OiPr)(3)) has been synthesized and employed for ring-opening polymerization of 1,4-dioxan-2-one in bulk as a single-component initiator. The influences of reaction conditions such as initiator concentration, reaction time, and reaction temperature on the polymerization were investigated. The kinetics indicated that the polymerization is first-order with respect to the monomer concentration. The Mechanistic investigations according to H-1 NMR spectrum analysis demonstrated that the polymerization of PDO proceeded through a coordination-insertion mechanism with a rupture of the acyl-oxygen bond of the monomer rather than the alkyl-oxygen bond cleavage.