Self-assembly of carbazole-based dendrimers by solvent vapor annealing: from fibers to spherulites.

Autor: Ding Z; State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences and Graduate University of the Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022, PR China., Xing R, Zheng L, Sun Y, Wang X, Ding J, Wang L, Han Y
Jazyk: angličtina
Zdroj: The journal of physical chemistry. B [J Phys Chem B] 2011 Dec 29; Vol. 115 (51), pp. 15159-66. Date of Electronic Publication: 2011 Dec 07.
DOI: 10.1021/jp2045492
Abstrakt: The self-assembly behavior of H1-BCz, a first-generation dendrimer with phenyl-carbazole as core and carbazole as dendrons, was systemically studied by solvent-vapor annealing. The morphologies of spin-coated H1-BCz film on various substrates changed from giant crystalline fibers of several millimeters to spherulites with a decrease in tetrahydrofuran vapor pressure. At high vapor pressure, dewetting easily took place in the amorphous films, and single fibers or fiber clusters formed. The fibers grew from nuclei formed at the place where it does not dewet. The fibers grew larger by continuous nucleation and growth at the growth front of the fiber until all the substance on the substrate was consumed. As the vapor pressure decreased, dewetting did not so easily happen, and fibers packed more tightly and spherulites were obtained. Through characterization of the crystals and films, we speculate that 3D H1-BCz crystal formed by overlapping 2D lamellar structure. The π-π interactions and van der Waals interactions among H1-BCz molecules and solvent may be the main force driving the self-assembly of H1-BCz.
(© 2011 American Chemical Society)
Databáze: MEDLINE