Determining Presence of Acrylic Additive in Concrete

Technique Used: Fourier Transform Infrared Spectroscopy (FTIR)

A concrete sample was submitted for testing to determine whether it contained a water soluble acylic (latex) additive. A portion of the sample was immersed in acidified water and then rinsed with deionized water. Some small pieces floated to the top of the water. This floating material was dried and then pressed into a thin film to be analyzed by FTIR. The resultant FTIR spectrum was compared to a library of FTIR reference spectra.

The figure below compares the sample spectrum to a reference spectrum of a water soluble acrylic polymer.

FTIR Spectrum of Concrete Sample

Reference Spectrum of Absoluble Acrylic

Figure 1: FTIR spectrum of sample (top) and reference spectrum of asoluble acrylic (bottom).