Imaging of Additives

Principles and Characteristics Classical spectroscopic techniques generate an average structure over the dimensions of the sample, and no information about the distribution of the 

Merging of spectroscopy with microscopy has generated an entirely new discipline, termed microspectroscopy, which allows measurement of the spatial distribution of chemical stractures in materials. Microspectrophotometry (MSP), primarily in the UVAHS and NIR ranges (220 to 2500 nm), has been practised in some way since the 1930s with emphasis on the microscope functionality [368, 369]. On the other hand, the recent convergence of infrared with microscopy accentuates the spectroscopic functionality. Microspectroscopy is a powerful tool for characterisation of micro samples, for examination of heterogeneous materials and for analysis of processes such as migration that involve spatial 

Key requirements for imaging experiments are an imaging method and a contrast mechanism. Various imaging modes may be distinguished (Table 5.38). Area excitation with area imaging detection is equivalent to the conventional microscope, telescope, and 

The second key requirement for an imaging techniques is a contrast mechanism, which is some property of the system that varies spatially in the same way as the sample properties to be mapped, e.g. a specific fragment in mass spectrometry, a specific vibrational group frequency, surface reflectivity, etc. In many cases, especially for polymers, samples do not have much inherent contrast under a visible light microscope. Additional contrast is desired. 

Area excitation with area imaging detection Conventional microscopy 

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This Chapter describes the use of both point mapping and global imaging techniques to study subtle spatial variations in polymer chemistry and morphology. Mapping and imaging of additives and crystallinity/molecular orientation in polymer articles will be illustrated [384]. Quantitative acoustic microscopy was reviewed [385] as well as scanning acoustic microscopy [386-388]. Laser ablation mi-croanalytical techniques are discussed in Chp. 3. 

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