Abstract
The governing parameters controlling the glass transition temperature of polymer-grafted particle systems are analyzed for the particular case of polystyrene (PS)-grafted silica colloids in the dense grafting limit. At a given degree of polymerization of surface-grafted chains the glass transition temperature is found to increase as compared to linear chain polymers of equivalent degree of polymerization. The difference in the glass transition temperature between polymer-grafted particle systems and their respective linear polymer analogs increases with decreasing degree of polymerization of surface-grafted chains and levels off at similar plateau values for particle brushes of distinct particle core size. The trend toward increased glass transition temperature is interpreted as a consequence of the increased steric hindrance in polymer-grafted particles that counteracts the relaxation of surface-grafted polymer chains. The increase in glass transition temperature is shown to be approximately consistent with the chain conformational regimes that are predicted on the basis of a Daoud-Cotton type scaling model.
Original language | English |
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Pages (from-to) | 9-16 |
Number of pages | 8 |
Journal | Macromolecular Symposia |
Volume | 331-332 |
Issue number | 1 |
DOIs | |
State | Published - Oct 2013 |
Keywords
- ATRP
- Brush
- Glass transition
- Nanocomposite
- Silica