Thermal Analysis of Adsorbed PMMA on Silica

Abstract

Modulated differential scanning calorimetry has been used to quantify the glass transitions of small adsorbed amounts of poly(methyl methacrylate) (PMMA) on silica. While a relatively narrow, single glass transition was found for bulk PMMA, broader two-component transitions were found for the adsorbed polymer. A two-state model based on loosely bound polymer (glass transition similar to bulk) and more tightly bound polymer (glass transition centered around 156 C) was used to interpret the thermograms. On the basis of this model, the amount of tightly bound polymer was found to be approximately 1.3 mg/m2, corresponding to a 1.1 nm thick layer. The change in heat capacity for the tightly bound polymer at the glass transition temperature was estimated to be about 16% of that of the bulk polymer.

Department(s)

Chemistry

Second Department

Chemical and Biochemical Engineering

Sponsor(s)

National Science Foundation (U.S.)

International Standard Serial Number (ISSN)

0743-7463

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2006 American Chemical Society (ACS), All rights reserved.

Publication Date

07 Apr 2006

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