Article (Scientific journals)
SAXS analysis of the morphology of biocompatible and biodegradable poly(ε-caprolactone-b-glycolide) copolymers1
Sobry, R.; Van den Bossche, Guy; Fontaine, F. et al.
1996In Journal of Molecular Structure, 383 (1-3), p. 63-68
Peer Reviewed verified by ORBi
 

Files


Full Text
Sobry_R_1996_J mol structure_383_1-3_63.pdf
Author postprint (191.78 kB)
Download
Full Text Parts
Sobry R 1996 J Mol Structure 63.pdf
Publisher postprint (458.02 kB)
Request a copy

The authors acknowledge Journal of Molecular Structure (Elsevier) for allowing them to archive this paper.


All documents in ORBi are protected by a user license.

Send to



Details



Keywords :
ring-opening polymerization (ROP); lactone
Abstract :
[en] Poly(epsilon-caprolacrone-b-glycolide) diblock copolyesters have been synthesized by the sequential polymerization of epsilon-caprolactone and glycolide as initiated by aluminium alkoxides. Copolymerization is typically ''living'' and yields copolyesters of perfectly controlled molecular weight and composition. Diblock molecular weight (Mn-PGA+Mn-PCL) ranges from 5700 to 42000 and the rho = Mn-PCL/Mn-PGA ratio varies from 1.5 to 13.1. Due to the inherent insolubility of the polyglycolide (PGA) segment in common organic solvent, the diblock copolyesters form stable non-aqueous colloidal dispersions e.g. in toluene, the stability of which results from the soluble poly(epsilon-caprolactone) (PCL) block. Combining all the experimental observations (PCS, TEM, WAXS, SAXS, AFM), a micelle model has been proposed which consists of a polyglycolide core surrounded with a corona of polycaprolactone (PCL). Both constituents are semi crystalline. From SAXS observations, the PGA core is better described by two concentric spheres. The internal sphere of a 5-6.7 nn diameter would essentially contain crystalline PGA. The diameter of the external sphere, D-PGA, is in the range from 6.2 to 9.6 nm, at least for the investigated diblock copolymers. As a rule, this diameter increases as rho decreases at constant molecular weight and as the diblock molecular weight increases at constant rho. A scattering peak (weak) is observed in the range from 10.8 to 15.5 nm and the Bragg distance is close mu D-PGA, where mu is equal to (1+3 rho/2)(1/3). From steric considerations, mu is the ratio between the diameter of the micelle and the diameter of the PGA core, so that this peak has been assigned to the characteristic intermicellar distance. At very small angles, several additional peaks are the signature of a hyperstructure which is possibly lamellar.
Research center :
Center for Education and Research on Macromolecules (CERM)
Disciplines :
Chemistry
Materials science & engineering
Author, co-author :
Sobry, R.;  Université de Liège - ULiège > Department of Physics > Laboratory of Experimental Physics
Van den Bossche, Guy ;  Université de Liège - ULiège > Department of Physics > Laboratory of Experimental Physics
Fontaine, F.;  Université de Liège - ULiège > Department of Physics > Laboratory of Experimental Physics
Barakat, Ibrahim;  Université de Liège - ULiège > Department of Chemistry > Center for Education and Research on Macromolecules (CERM)
Dubois, Philippe ;  Université de Liège - ULiège > Department of Chemistry > Center for Education and Research on Macromolecules (CERM)
Jérôme, Robert ;  Université de Liège - ULiège > Department of Chemistry > Center for Education and Research on Macromolecules (CERM)
Language :
English
Title :
SAXS analysis of the morphology of biocompatible and biodegradable poly(ε-caprolactone-b-glycolide) copolymers1
Publication date :
30 September 1996
Journal title :
Journal of Molecular Structure
ISSN :
0022-2860
eISSN :
1872-8014
Publisher :
Elsevier Science Bv, Amsterdam, Netherlands
Volume :
383
Issue :
1-3
Pages :
63-68
Peer reviewed :
Peer Reviewed verified by ORBi
Funders :
BELSPO - SPP Politique scientifique - Service Public Fédéral de Programmation Politique scientifique
F.R.S.-FNRS - Fonds de la Recherche Scientifique [BE]
3M Belgium
Available on ORBi :
since 29 June 2009

Statistics


Number of views
109 (13 by ULiège)
Number of downloads
209 (6 by ULiège)

Scopus citations®
 
7
Scopus citations®
without self-citations
4
OpenCitations
 
6

Bibliography


Similar publications



Contact ORBi