Abstract
Dielectric spectroscopy is used to measure polymer relaxation in styrene-butadiene rubber (SBR) composites. In addition to the bulk polymer relaxation, the SBR nanocomposites also exhibit a slower relaxation attributed to polymer relaxation at the polymer-nanoparticle interface. The glass transition temperature associated with the slower relaxation is used as a way to quantify the interaction strength between the polymer and the surface. Comparisons were made among composites containing nanoclay, silica, and carbon black. The interfacial relaxation glass transition temperature of SBR-clay nanocomposites is more than 80 °C higher than the SBR bulk glass transition temperature. An interfacial mode was also observed for SBR-silica nanocomposites, but the interfacial glass transition temperature of SBR-silica nanocomposite is somewhat lower than that of clay nanocomposites. An interfacial mode is also seen in the carbon black filled system, but the signal is too weak to analyze quantitatively. The interfacial polymer relaxation in SBR-clay nanocomposites is stronger compared to both SBR-carbon black and SBR-silica composites indicating a stronger interfacial interaction in the nanocomposites containing clay. These results are consistent with dynamic shear rheology and dynamic mechanical analysis measurements showing a more pronounced reinforcement for the clay nanocomposites. Comparisons were also made among clay nanocomposites using different SBRs of varying styrene concentration and architecture. The interfacial glass transition temperature of SBR-clay nanocomposites increases as the amount of styrene in SBR increases indicating that styrene interacts more strongly than butadiene with clay. © 2011 American Chemical Society.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 6162-6171 |
| Number of pages | 10 |
| Journal | Macromolecules |
| Volume | 44 |
| Issue number | 15 |
| DOIs | |
| State | Published - Aug 9 2011 |
| Externally published | Yes |
Bibliographical note
KAUST Repository Item: Exported on 2020-10-01Acknowledged KAUST grant number(s): KUS-C1-018-02
Acknowledgements: This publication is based on work supported in part by Award No. KUS-C1-018-02, made by King Abdullah University of Science and Technology. Additional support was provided by Michelin under the guidance of Julie McCormick, Stephanie Nesbitt, and Aiying Wang. L.V. also gratefully acknowledges support from the NSFGRP fellowship. This work made use of the Cornell Center for Materials Research Experimental Facilities. S.H.A. would like to acknowledge that part of this research was sponsored by the Greek General Secretariat of Research and Technology (ΠΕΝΕΔ 2003 programme, project 03EΔ581) and by the European Union (STREP Programme, project NMP3-CT-2005-506621). We thank Haris Retsos for his contribution to the initial work in dielectric spectroscopy, Antonios Kelarakis for his work on rheological and DMA measurements, and Luis Estevez for his work in TEM imaging. We also thank Richard Vaia and Creighton Thomas for helpful discussions.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.