期刊
JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS
卷 52, 期 22, 页码 1462-1468出版社
WILEY
DOI: 10.1002/polb.23583
关键词
differential scanning calorimetry (DSC); glass transition; polycarbonate; thin films
资金
- Office of Naval Research [N00014-11-1-0424]
- John R. Bradford endowment at Texas Tech University
- ACS-PRF [52426-ND7]
Flash differential scanning calorimetry was used to study the glass transition temperature T-g of polycarbonate ultrathin films. The investigation was made as a function of film thickness from 22 to 350 nm and over a range of cooling rates from 0.1 to 1000 K/s. Polycarbonate spin cast films were floated on a layer of grease on the calorimetric chip. The results show a greatly reduced glass temperature for the thinnest films relative to the macroscopic value. We also observed that the magnitude of the glass temperature reduction decreases as the cooling rate increases with the highest cooling rates showing little thickness dependence of the T-g. Dynamic fragility and activation energy at T-g were found to decrease with decreasing film thickness. The results are discussed in the context of literature reports for supported and freely standing polycarbonate films. (c) 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014, 52, 1462-1468
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据