Related Experiment Videos
Effect of density fluctuating supercritical carbon dioxide on polymer interfaces
Tadanori Koga1, J L Jerome, Y-S Seo
1Department of Materials Science & Engineering, State University of New York at Stony Brook, Stony Brook, New York 11794-2275, USA. tkoga@notes.cc.sunsyb.edu
Langmuir : the ACS Journal of Surfaces and Colloids
|June 29, 2005
Summary
Carbon dioxide (CO2) sorption significantly enhances the compatibility of immiscible polystyrene (PS) and polybutadiene (PB) polymer blends. This CO2 sorption dramatically increases the interfacial width between PS and PB layers, even at room temperature.
Area of Science:
- Polymer Science
- Materials Science
- Physical Chemistry
Background:
- Immiscible polymer blends often exhibit poor compatibility, limiting their applications.
- Understanding interfacial behavior is crucial for tailoring material properties.
Purpose of the Study:
- To investigate the impact of carbon dioxide (CO2) sorption on the interfacial compatibility of immiscible polystyrene (PS) and polybutadiene (PB) bilayers.
- To quantify changes in interfacial width induced by CO2 exposure.
Main Methods:
- In situ neutron reflectivity measurements were employed.
- Deuterium labeling of either polystyrene or polybutadiene was used to track polymer distribution.
- Bilayer samples were exposed to CO2 under specific temperature and pressure conditions near the critical point of CO2.
Main Results:
- Excess CO2 molecules were found to adsorb to both the polystyrene and polybutadiene layers.
- CO2 sorption significantly increased the interfacial width between the PS and PB layers, reaching up to 100 angstroms.
- This widening occurred even near room temperature, a substantial increase compared to the ~40 angstroms observed without CO2.
Conclusions:
- CO2 sorption acts as a plasticizer, enhancing the miscibility and compatibility of immiscible PS/PB bilayers.
- The observed increase in interfacial width demonstrates a significant alteration of polymer chain mobility and interfacial structure due to CO2 presence.
- This finding opens possibilities for using CO2 as a processing aid to improve polymer blend properties.