Contraction and reexpansion of polymer thin films

被引：50

作者：

Miyazaki, T

Nishida, K

Kanaya, T ^{[1
]}

机构：

[1] Kyoto Univ, Chem Res Inst, Kyoto 6110011, Japan

[2] Nitto Denko Corp, Ibaraki, Osaka 5678680, Japan

来源：

PHYSICAL REVIEW E | 2004年 / 69卷 / 02期

关键词：

D O I：

10.1103/PhysRevE.69.022801

中图分类号：

O35 [流体力学]; O53 [等离子体物理学];

学科分类号：

070204 ; 080103 ; 080704 ;

摘要：

We report x-ray reflectivity measurements on polystyrene thin films supported on silicon wafer. In annealing experiments, we found fast and slow contraction processes in the thin films above the glass transition temperature. The former is the normal relaxation (annealing) process observed in bulk, and the latter is unexpected and enhanced in thin films below similar to20 nm. In addition, we found unexpected extremely slow reexpansion processes in the glassy state. These unexpected very slow processes are discussed in terms of lateral contraction and expansion processes driven by entropic changes at the interfaces and the difference of the expansivities between polystyrene and silicon wafer.

引用

页码：022801 / 1

页数：4

共 20 条

[1] Molecular weight dependence of reductions in the glass transition temperature of thin, freely standing polymer films [J].