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An AFM Study of Poly( L ‐lactic acid) and Poly( D ‐lactic acid) Macromolecules and Their Stereocomplexes at the Solid‐Air Interface
Author(s) -
Narladkar Ashok,
Balnois Eric,
Grohens Yves
Publication year - 2006
Publication title -
macromolecular symposia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.257
H-Index - 76
eISSN - 1521-3900
pISSN - 1022-1360
DOI - 10.1002/masy.200650906
Subject(s) - nucleation , enantiomer , nanometre , macromolecule , atomic force microscopy , lactic acid , chemical engineering , fibril , chemistry , crystallography , materials science , polymer chemistry , nanotechnology , stereochemistry , composite material , organic chemistry , bacteria , biochemistry , genetics , biology , engineering
The self assembly of PLA enantiomers have been studied at the nanometer scale using atomic force microscopy. At first, the conformation of D and L PLA macromolecules in dilute regime and the initial state of aggregation of both enantiomers were successively observed and compared with the aggregation of PLLA/PDLA blends. Our results points out differences in the aggregates structure between the homo‐aggregates of each enantiomers and the 3 Dimensional stereocomplexes formed with racemic mixture of D and L entities. On the one hand, D or L PLA chains, which adopt a rigid conformation in dilute regime, form gradually aggregates that tend to grow from a nucleation center. On the other hand, stereocomplexes have a non‐compact structure and are elongated with height variations within the fibrils that support the side by side aggregation of D and L helical structures to form thicker fibrils.