Characterization of Heterogeneous Regions in Polymer Systems Using Tapping Mode and Force Mode Atomic Force Microscopy

Published

November 1, 2000

Author(s)

R Raghavan, Mark R. VanLandingham, Xiaohong Gu, Tinh Nguyen

Abstract

Characterization of polymer coating surfaces is crucial to understanding and predicting the long-term performance of coatings in aggressive environments. The exposed polymer surface and near-surface regions can differ from the bulk polymer film both chemically and mechanically, which can effect the durability of the coating and its ability to protect the underlying substrate. In this study, atomic force microscopy (AFM) is used to investigate the heterogeneity of blended films of poly (methylmethacrylate) (PMMA) and polybutadiene (PB) on silicon substrates before and after annealing. The blended films with different ratios of PMMA to PB are prepared by spin casting onto silicon substrates from solution. The surface morphology and composition of these cast films are investigated using tapping mode and force mode AFM. Annealing the samples in air at 75 C + 5 C causes changes in the relative chemical and mechanical differences between PMMA and PB, so the phase image contrast is studied as a function of annealing time. The effect of tapping force level on phase image contrast is also explored. To identify the different components in polymer blends and to understand the influence of relative surface stiffness on the phase images, nanoscale indentation measurements

Citation

Langmuir

Volume

16

Issue

No. 24

Pub Type

Journals

Download Paper

Local Download

Keywords

blends, chemical properties, coatings, mechanical properties, microstructure, nanoindentation, phase contrast

Citation

Raghavan, R. , VanLandingham, M. , Gu, X. and Nguyen, T. (2000), Characterization of Heterogeneous Regions in Polymer Systems Using Tapping Mode and Force Mode Atomic Force Microscopy, Langmuir, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=860238 (Accessed March 22, 2025)