Issue 13, 2017

Grafting density dominant glass transition of dry polystyrene brushes

Abstract

The effects of the grafting densities (σp), molecular weights (Mn) and thicknesses of dry polystyrene (PS) brushes on their glass transition temperature (Tbrushg) were investigated by ellipsometry. The results show that Tbrushg strongly depends on the grafting density of the PS brushes. The Tbrushg of the PS brushes with σp > 0.30 increases with decreasing Mn (or brush thickness) and is mainly dominated by entropic effects, in which the grafted chains are highly extended along the film thickness direction resulting in a sharp reduction in configurational entropy. The Tbrushg of PS brushes with σp < 0.30 decreases with decreasing Mn (or brush thickness) which is mainly dominated by surface effects. For intermediate-density brushes (σp = 0.30), Tbrushg becomes independent of Mn or brush thickness. The reason for this grafting density dependence of Tbrushg is attributed to the transition of the PS brush conformation from mushroom-to-brush.

Graphical abstract: Grafting density dominant glass transition of dry polystyrene brushes

Supplementary files

Article information

Article type
Paper
Submitted
15 Dec 2016
Accepted
25 Jan 2017
First published
26 Jan 2017

Soft Matter, 2017,13, 2426-2436

Grafting density dominant glass transition of dry polystyrene brushes

B. Zuo, S. Zhang, C. Niu, H. Zhou, S. Sun and X. Wang, Soft Matter, 2017, 13, 2426 DOI: 10.1039/C6SM02790C

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements