Chapter 10. Infrared Spectra of Polymers: Introduction

Summary

Chapter 10 is concerned with functional groups that contain NO bonds or Si, P, S or the halogen atoms. With the exception of the XH stretches derived from these elements and the nitroso (NO) and nitrite groups (ONO), the large majority of the group frequencies associated with these elements fall below 1500 cm⁻¹ in the fingerprint region of the spectrum.

The more important of the silicon group frequencies are associated with SiH stretches, the SiCH₃ methyl deformations, a mixed SiCH₃ stretch and the SiOSi antisymmetric stretch.

Phosphorous compounds are examined in much the same fashion as the silicon systems. The P=O stretch is discussed in some detail. It can provide considerable information about the environment of the P=O group.

Sulfur derivatives behave in a manner similar to phosphorous compounds. A discussion of stretching modes considers SH, CS and SS, and S=O groups. The latter system (S=O stretch) is examined in detail because considerable information about the local environment of the S=O system can be extracted from the vibrational spectra. This chapter completes the discussions of hetero-atom group frequencies which started in Chapter 7.

Exercise Section II which follows Chapter 10 requires a review of Chapters 7–10.

Exercise Section II is focused on developing experience at interpreting the spectra of organic systems possessing hetero-atom functional groups. It consists of six exercises (Exercises 5–10) which are composed of six pairs of infrared and Raman spectra, two single infrared spectra plus a very old infrared prism reference spectrum.