NIR transmission spectra of small polypropylene objects showing the overtones and combinations bands of C-H bonds.

       Raman spectra of polypropylene objects. In blue the C-C and C-H bending bonds and in red the C-H stretching fundamental vibrations.

          Low resolution infrared spectrum of a thin section of polypropylene ( molten plastic on a glass sheet). Spectrum deconvolution with Fityk program.