Abstract
Modern polymers are seldom used as pure materials. In most cases, a mixture of different polymers are combined to give the desired physical characteristics. For example, the rigidity of polystyrene is often combined with an elastic polymer to produce stiff yet shock resistant materials. There are many methods that can be used to generate these mixtures but one of the most common is to simply assemble the polymers into layers and create a polymer laminate. Raman and infrared spectroscopy are two complementary, nondestructive techniques that are finding increased application for polymer analysis. The most widely used structural spectroscopic method is Fourier Transform infrared (FT-IR). Raman spectroscopy is gaining favor, even though the equipment can require a higher initial investment, because it requires little to no sample preparation, is not as sensitive to aqueous solutions, and produces easily interpreted spectra for identification of the polymeric materials. Infrared spectroscopy is used for molecules with functional groups containing permanent dipole moments, while Raman works best for samples with functional groups that are polarizable with molecular vibration. Thus, Raman can give structural information on infrared inactive bonds and vice-versa. The application of infrared and Raman spectroscopy to the characterization of polymer-based systems continues to be an active area in the literature. General reviews of vibrational spectroscopy for the characterization of polymers are presented first, followed by a review of the analysis of polymer laminates using FT-IR and Raman spectroscopy. In conclusion we will describe the advantages of using the two techniques simultaneously.
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