| People | Locations | Statistics |
|---|---|---|
| Naji, M. |
| |
| Motta, Antonella |
| |
| Aletan, Dirar |
| |
| Mohamed, Tarek |
| |
| Ertürk, Emre |
| |
| Taccardi, Nicola |
| |
| Kononenko, Denys |
| |
| Petrov, R. H. | Madrid |
|
| Alshaaer, Mazen | Brussels |
|
| Bih, L. |
| |
| Casati, R. |
| |
| Muller, Hermance |
| |
| Kočí, Jan | Prague |
|
| Šuljagić, Marija |
| |
| Kalteremidou, Kalliopi-Artemi | Brussels |
|
| Azam, Siraj |
| |
| Ospanova, Alyiya |
| |
| Blanpain, Bart |
| |
| Ali, M. A. |
| |
| Popa, V. |
| |
| Rančić, M. |
| |
| Ollier, Nadège |
| |
| Azevedo, Nuno Monteiro |
| |
| Landes, Michael |
| |
| Rignanese, Gian-Marco |
|
Tsui, Ophelia Kwan Chui
in Cooperation with on an Cooperation-Score of 37%
Topics
Publications (3/3 displayed)
- 2013Glass Transition Temperature of Polymer-Nanoparticle Composites: Effect of Polymer-Particle Interfacial Energycitations
- 2004Effect of Polymer-Substrate Interactions on the Glass Transition of Polymer Thin Films
- 2001Effect of Interfacial Interactions on the Glass Transition of Polymer Thin Filmscitations
Places of action
| Organizations | Location | People |
|---|
document
Effect of Polymer-Substrate Interactions on the Glass Transition of Polymer Thin Films
Abstract
It has been suggested that when the polymer-substrate interaction, s, in a polymer film supported by substrate is strongly favorable, the Tg of the polymer film may increase with decreasing film thickness; but the opposite prevails if the interaction is less than weakly favorable. We present a quantitative study of the glass transition temperature, Tg, in thin films of polystyrene (PS) as a function of s by measuring the change in the thermal expansion using x-ray reflectivity. Using random copolymer of styrene and methylmethacryalte anchored to the substrate, s could be varied by varying the styrene content, f. With a fixed PS film thickness of 33 nm, the Tg was depressed by ~20 deg C as f was decreased from 1 to 0.7. An analysis analogous to the Gibbs-Thompson model indicated that the surface energy was not a suitable parameter to use to describe the effect of interfacial interactions on the Tg of polymer thin films. Instead, an associated local fractional change in the polymer mass density at the substrate interface was introduced to describe the observed change in Tg with different s.