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Stacking of main chain-crown ether polymers in thin films
Daniel R Rueda1, Aurora Nogales, Jaime J Hernandez
1Instituto de Estructura de la Materia, CSIC, Serrano 119, 28006, Madrid, Spain. emdaniel@iem.cfmac.csic.es
Langmuir : the ACS Journal of Surfaces and Colloids
|November 2, 2007
Summary
This study developed polymer thin films with dibenzo-18-crown-6 ether units. Thermal treatment enhanced nanostructure and molecular column orientation in these polymer films.
Area of Science:
- Polymer Science
- Materials Science
- Nanotechnology
Background:
- Dibenzo-18-crown-6 ether (DB18C6) units incorporated into polymer main chains offer unique properties.
- Aliphatic spacers of varying lengths (10C, 14C) influence polymer chain behavior.
- Thin film fabrication is crucial for advanced material applications.
Purpose of the Study:
- To synthesize and characterize polymer thin films containing DB18C6 units.
- To investigate the effect of aliphatic spacer length on film nanostructure.
- To evaluate the impact of thermal treatment on film morphology and molecular orientation.
Main Methods:
- Spin coating of polymer solutions in chloroform onto silicon substrates.
- Characterization using reflectivity spectra and atomic force microscopy (AFM) for film quality.
- Grazing incidence small-angle X-ray scattering (GISAXS) to analyze nanostructure and molecular orientation.
Main Results:
- Homogeneous polymer thin films (9-70 nm) were successfully prepared.
- GISAXS revealed out-of-plane structure correlations related to polymer repeating unit length.
- Stacked molecular columns within the polymer films exhibited orientation.
- Thermal treatment improved nanostructure, increasing lamellar coherence and vertical molecular orientation.
Conclusions:
- Polymer thin films with DB18C6 units can be controllably fabricated.
- Spacer length and thermal treatment are key factors in controlling nanostructure.
- Enhanced molecular ordering in thin films can be achieved through post-fabrication processing.
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