A-B-A-Triblock and multiblock copolyesters prepared from ε-caprolactone, glycolide and l-lactide by means of bismuth subsalicylate

Autor:	Simon Rost, Hans R. Kricheldorf
Rok vydání:	2005
Předmět:	Materials science Lactide Polymers and Plastics Organic Chemistry chemistry.chemical_element Transesterification Amorphous solid Bismuth Catalysis chemistry.chemical_compound chemistry Polymer chemistry Materials Chemistry Copolymer Glass transition Caprolactone
Zdroj:	Polymer. 46:3248-3256
ISSN:	0032-3861
DOI:	10.1016/j.polymer.2005.02.004
Popis:	Bismuth (III) subsalicylate, a commercial drug, was used as catalyst for 1,4-butanediol-initiated copolymerizations of e-caprolactone (eCL) and glycolide (GL). Telechelic copolyesters having two OH-endgroups and predominantly alternating sequences were obtained. These copolyesters are amorphous with glass transition temperatures (Tgs) below −30 °C. In a second series of polymerizations, in situ chain extension with l -lactide (LLA) was performed, whereby A-B-A triblock copolymers were obtained without significant transesterification between A- and B-blocks. Finally, these A-B-A triblock copolymers were transformed into multiblock copolymers by chain extension with 1,6-hexamethylene diisocyanate. The block copolymers were characterized by 1H and 13C NMR spectroscopy, by viscosity, SEC and DSC measurements.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::116cd3fca8f93af3d2c91c1252a3e349 https://doi.org/10.1016/j.polymer.2005.02.004 Zobrazit plný text záznamu Full Text from ScienceDirect