Raman spectroscopy of polymer latexes

Abstract

The influence of elastic light scattering on the Raman signal of polymer latexes was investigated by varying the sample position relative to the confocal Raman probe. Measurements on polystyrene latexes revealed that the absolute Raman signal is very sensitive to the alignment of the sample. Furthermore, it was shown that for particle sizes below 140 nm and solid weight contents below 20%, changes in the absolute Raman signal can be described fairly well by turbidity laws. For larger particle sizes and higher solid weight contents deviations occur, but a correlation between these variables and the Raman signal still exists. In contrast, the normalized intensities are not influenced by varying the sample alignment in measurements on polymer latexes when using an excitation laser source at 532 nm. The important consequence of this is that the determination of chemical composition is not influenced by the elastic light scattering effects.

A Raman microprobe study of electrical treeing in polyethylene

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Whispering gallery modes in photoluminescence and Raman spectra of a spherical microcavity with CdTe quantum dots: anti-Stokes emission and interference effects

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A Critical Overview of Sensors for Monitoring Polymerizations

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