Authors
Douglas Dukes, Yu Li, Sarah Lewis, Brian Benicewicz, Linda Schadler, Sanat K Kumar
Publication date
2010/2/9
Journal
Macromolecules
Volume
43
Issue
3
Pages
1564-1570
Publisher
American Chemical Society
Description
We examine the structure of densely grafted polymer layers grown from the surfaces of spherical nanoparticles over a broad range of graft densities and chain lengths. Dynamic light scattering (DLS) experiments show that the hydrodynamic thickness of the polymer layer, h, scales as h ∝ N4/5 for short chains and high grafting densities, that is, in the concentrated polymer brush (CPB) regime, whereas h ∝ N3/5 for long enough chains (semidilute polymer brush, SDPB). The mean field theory of Wijmans and Zhulina is able to collapse approximately all of our data and those in the existing literature (even on other polymers) into an apparently universal form. From these findings, we conclude that the result h ∝ N4/5 for the CPB is an intermediate crossover scaling, relevant to particles of finite curvature, analogous to the h ∝ N observed for concentrated flat brushes. Second, the scaling h ∝ N3/5 uniquely reflects the …
Total citations
Scholar articles
D Dukes, Y Li, S Lewis, B Benicewicz, L Schadler… - Macromolecules, 2010