Qualitative and Quantitative Analysis of Polymers and Rubbers by Vibrational Spectroscopy

Abstract

This article begins with a short introduction on the range of sample forms, types and properties. This is followed by concise descriptions of the various sampling techniques as they apply to polymer analyses by mid‐infrared and Raman spectroscopy. (The article does not cover near‐infrared spectroscopy). More specific applications sections then follow discussions of qualitative and quantitative analysis and peculiarities associated with polymer mid‐infrared and Raman spectra. These include measurement of molecular orientation, determining end group concentrations and branching, studies of hydrogen bonding and blend miscibility, copolymer composition, polymerisation and cure studies, degradation and oxidation, and determining optical properties and constants. Brief sections are included also on chromatography coupled with FT‐IR, EGA/FT‐IR and TGA/FT‐IR and pyrolysis‐infrared. Discussed also are 2D‐IR, process measurements and microspectroscopy applications. This article is essentially a prelude to the more specialised articles that follow on in this section (Analysis and Characterization of Polymers and Rubbers) in this Handbook.

Real-Time Infrared Determination of Photoinitiated Copolymerization Reactivity Ratios: Application of the Hilbert Transform and Critical Evaluation of Data Analysis Techniques

“…Description Peak Fitted Deconvolution. The univariate method is limited when different functional group specific bands overlap each other. Peak fitted deconvolution is another conventional data analysis technique which is very useful if there are no isolated bands available in the FTIR spectrum that can be used for the univariate method.…”

“…Employment of 2D correlation spectroscopy provides a good indication which component reacts predominantly first as well as the exact peak positions in a reacting mixture (in principle required for a correct deconvolution procedure). Other analytical data evaluation techniques are for instance the univariate method, peak fitted deconvolution, and multivariant techniques like SIMPLISMA (simple to use interactive self-modeling mixture analysis) and multivariate curve resolution (MCR). , An often unmentioned requirement is that all the different analytical techniques should yield the same result, as the reactivity ratios do not depend on the method of data treatment. Taking into account the sampling and specific sample problems, listed above, it has been considered worthwhile to start a critical evaluation of different advanced multivariate data analysis techniques for determination of the reactivity ratios of various photoinitiated copolymerizations.…”

Characterization of polymer properties and identification of additives in commercially available research plastics

“…As polyurethanes are extremely complex and made with many different formulations, this data highlights the potential to use EGA using TGA-FTIR for some product characterization. 76 Although EGA with TGA-FTIR may provide insight into the structure of this polymer, this technique alone cannot distinguish between a thermal degradation product or a small molecule additive. The FTIR spectra for EVA-3 exhibited a 77% library match for vinylbenzene and 3-methyl-1-phenyl-3-pentanol, indicating the presence of aromatic structures.…”