Infrared spectroscopy plasticisers

Infrared spectroscopy is a major tool for polymer and rubber identification [11,12]. Infrared analysis usually suffices for identification of the plastic material provided absence of complications by interferences from heavy loadings of additives, such as pigments or fillers. As additives can impede the unambiguous assignment of a plastic, it is frequently necessary to separate the plastic from the additives. For example, heavily plasticised PVC may contain up to 60% of a plasticiser, which needs to be removed prior to attempted identification of the polymer. Also an ester plasticiser contained in a nitrile rubber may obscure identification of the polymer. Because typical rubber compounds only contain some 50% polymer direct FUR analysis rarely provides a definitive answer. It is usually necessary first... 

Surface modification of polyvinyl chloride films, both plasticised and unplasticised, using amino thiophenol in dimethyl formamide and water mixtures, was examined using attenuated total reflection fourier transform infrared spectroscopy, Raman spectroscopy and nuclear magnetic resonance spectroscopy. Reaction kinetics, and the amount of dioctyl phthalate plasticiser leached out during the reaction were determined. Surface selectivity and degree of modification was found to depend on reaction time. 19 refs. 

It was determined that the shear rate in PVC passing through a copper wire coating die was in excess of 4000000 Is. This resulted in volatilisation of the dioctyl phthalate plasticiser and changes in the polymer molecular structure, as determined by infrared spectroscopy. The flow was studied using capillary rheometry with a die of a 0.15 mm diameter. It was concluded that the change in... 

Varob yev and Vettegren [22] used infrared spectroscopy to determine temperature transitions in PC. Thermal transitions in PC were determined from the concentration variation of the residual solvent or plasticiser. 

Infrared spectroscopy (IR) is used extensively in the analysis of plastics. It is a very good, relatively quick technique for the determination of the polymer present in a plastic product. Unlike rabbers, where the majority of compounds contain additives such as carbon black and plasticisers that can interfere with the infrared data obtained, it is normally possible to record infrared spectra directly from the plastic sample using either a surface technique (e.g., attenuated total reflectance (ATR) spectroscopy) or in transmission through the sample from a film produced by pressing a specimen above its glass transition or melting point. 

Since infrared (IR) spectroscopy is one of the most widely used techniques for the identification of materials at the molecular level, it has been extensively used to characterise the rubbery materials. In this chapter the rubbery materials encompass PE, plasticised PVC, thermoplastic elastomers and ionomers. 

The Coblentz Society publish infrared spectra of numerous compounds, gases and vapours, halogenated hydrocarbons, plasticisers, and industrial chemicals. A large collection of spectra may be found in the Documentation of Molecular Spectroscopy (DMS) system which also covers Raman and micro-wave spectroscopy. The American Petroleum Institute (API) have published a large collection of spectra, mainly of hydrocarbons and compounds relevant to the petroleum industry. The Infrared Data Committee of Japan (1RDC) ° published a collection similar to that of DMS. Mecke and Langenbucher have published a small collection of infrared spectra of selected chemical compounds. 

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