Functional group absorptions

Functional Group Absorption (cm ) Intensity Functional Group Absorption cm 1) Intensity... 

Type of Compound Infrared Absorption due to Following Functional Groups Absorption Range (cm-1) Mass Spectra m/z Signal... 

Characterization of the donor bound polymers follows from their spectroscopic (ir and uv-vis KBr) properties in comparison with the starting donor monomers, and from elemental analyses. That the donors are covalently bound to the polymer and not present as unreacted monomers can be seen by the absence of the characteristic monomer functional group absorption (i.e. -OH, COzH) in the donor bound polymer. For example in Figure 1, the comparative ir spectra of p-hydroxyphenyl-TTF monomer and this donor covalently bound to linear and to cross-linked polysytrene are given. Except for the presence of the hydroxyl absorption in the monomer, all three spectra are essentially identical, indicating a rather clean polymer attachment reaction. 

Functional Group Absorption Range Example Example Compound V... 

Functional Group Absorption Ratige (cm 1) Example (cm-1) Example Compound... 

Functional Group Absorption Range (cm ) Example cm ) Example Compbund... 

Figure 2 shows the NIR spectra of soybeans and rice, including their main components such as water, protein, starch and oil. The more light absorbed, the higher the absorbance becomes. The absorption bands of each component depend on their specific functional groups. Absorption bands observed are due to their components in both rice and soybeans. 

The uses of IR spectra in identification, classification and mechanistic studies have been well documented. Tests for the identification of plastics utilized in Naval ordnance weaponry are discussed in Ref 21. Correlations between polymeric structure and ablative properties using IR spectroscopy have been obtained by monitoring changes in functional group absorption,properties.(Ref 12). The application of IR spectroscopy to the detection of more than 40 of the most common constituents of primers, tracers, igniters, incendiaries,... 

The remarkable versatility of NMR as an analytical method has diminished the importance of IR analysis in modern laboratories but it remains a very useful technique. The very small amount of sample required and the prominence of functional group absorption means that the progress of a reaction can be monitored very conveniently. For example, the reduction of an aldehyde to an alcohol will be accompanied by the disappearance of the prominent C=0 peak and the appearance of a C—OH absorption. Because both peaks are so readily identifiable in a small sample, the reaction is easy to follow and its completeness can be assayed. 

Functional Group Absorption Range (cm" ) Example (cm"b Example Compound... 

Fig. 28.6 Simplified correlation chart of functional group absorptions.

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