Summary
A commercial calcium dimethoxide and an in-situ generated calcium methoxide prepared from bis(tetrahydrofuran)calcium bis[bis(trimethylsilyl)amide] and methanol, were investigated as initiators for the ring-opening polymerization of ε-caprolactone and L-lactide. Commercial calcium dimethoxide initiated rapid ε-caprolactone polymerization at 120°C in bulk to give quantitatively a polymer with a polydispersity index around 1.3. Significant racemization was observed for L-lactide polymerization. The In-situ formed calcium methoxide promoted the solution polymerization of both ε-caprolactone and L-lactide to high conversion at room temperature over a short time period, yielding the corresponding polyesters with narrow molecular weight distribution. NMR spectra showed that the poly(L-lactide) isolated had a purely isotactic microstructure. The initiator efficiency could be tuned by varying the molar ratio of methanol and bis(tetrahydrofuran)calcium bis[bis(trimethylsilyl)amide].
Similar content being viewed by others
Author information
Authors and Affiliations
Additional information
Received: 11 August 2000/Revised version: 21 December 2000/Accepted: 3 January 2001
Rights and permissions
About this article
Cite this article
Zhong, Z., Ankoné, M., Dijkstra, P. et al. Calcium methoxide initiated ring-opening polymerization of ε-caprolactone and L-lactide. Polymer Bulletin 46, 51–57 (2001). https://doi.org/10.1007/s002890170088
Issue Date:
DOI: https://doi.org/10.1007/s002890170088