Processes of Ordered Structure Formation in Polypeptide Thin Film Solutions
An experimental study is presented on the hierarchical assembly of α-helical block copolymers polystyrene–poly(γ-benzyl-L-glutamate) into anisotropic ordered structures. We transformed thin solid films into solutions through exposure to solvent vapor and studied the nucleation and growth of ordered...
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Published in | Advances in polymer science Vol. 242; pp. 117 - 149 |
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Main Authors | , , |
Format | Book Chapter Journal Article |
Language | English |
Published |
Berlin, Heidelberg
Springer Berlin Heidelberg
01.01.2011
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Series | Advances in Polymer Science |
Subjects | |
Online Access | Get full text |
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Summary: | An experimental study is presented on the hierarchical assembly of α-helical block copolymers polystyrene–poly(γ-benzyl-L-glutamate) into anisotropic ordered structures. We transformed thin solid films into solutions through exposure to solvent vapor and studied the nucleation and growth of ordered three- dimensional structures in such solutions, with emphasis on the dependence of these processes on supersaturation with respect to the solubility limit. Interestingly, polymer solubility could be significantly influenced via variation of humidity in the surrounding gas phase. It is concluded that the interfacial tension between the ordered structures and the solution increased with humidity. The same effect was observed for other protic non-solvents in the surrounding gas phase and is attributed to a complexation of poly(γ-benzyl-L-glutamate) by protic non-solvent molecules (via hydrogen-bonding interactions). This change of polymer solubility was demonstrated to be reversible by addition or removal of small amounts of protic non-solvent in the surrounding gas phase. At a constant polymer concentration, ordered ellipsoidal structures could be dissolved by removing water or methanol present in the solution. Such structures formed once again when water or methanol was reintroduced via the vapor phase. |
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Bibliography: | USDOE Office of Science (SC) DE-AC02-06CH11357 ANL/CNM/JA-65135 |
ISBN: | 9783642222962 364222296X |
ISSN: | 0065-3195 1436-5030 |
DOI: | 10.1007/12_2010_67 |