Stereocomplex formation in ABA triblock copolymers of poly(lactide) (A) and poly(ethylene glycol) (B)

Stevels, Willem M. and Ankone, Marc J.K. and Dijkstra, Pieter J. and Feijen, Jan (1995) Stereocomplex formation in ABA triblock copolymers of poly(lactide) (A) and poly(ethylene glycol) (B). Macromolecular Chemistry and Physics, 196 (11). pp. 3687-3694. ISSN 1022-1352

Preview

PDF
415Kb

Abstract:	Two series of triblock copolymers of poly(ethylene glycol) (PEG, number-average molecular weight [bar M ]n = 6000) and poly(L-lactide) (PLLA) or poly(D-lactide) (PDLA) were prepared by ring-opening polymerization of lactide initiated by PEG end groups using stannous octoate as a catalyst, either in refluxing toluene or in the melt at 175°C. The weight percentage of PLA in the polymers varied between 15 and 75 wt.-%. Blends of polymers containing blocks of opposite chirality were prepared by co-precipitation from homogeneous solutions. The melting temperatures of the crystalline PEG and PLA phases strongly depended on the composition of the polymers. The melting temperature of the PLA phase in the blends was approximately 40°C higher than that of the single block copolymers. Stereocomplex formation between blocks of enantiomeric poly(lactides) in PEG/PLA block copolymers was established for the first time. Water uptake of polymeric films prepared by solution casting was solely determined by the PEG content of the film.
Item Type:	Article
Copyright:	© 1995 Wiley InterScience
Faculty:	Science and Technology (TNW)
Research Group:	Polymer Chemistry and BioMaterials (PBM)
Link to this item:	http://purl.utwente.nl/publications/71209
Official URL:	http://dx.doi.org/10.1002/macp.1995.021961121
Export this item as:	BibTeX EndNote HTML Citation Reference Manager

Show download statistics for this publication

Repository Staff Only: item control page

Metis ID: 105352