Figure 2.

Fourier-transform infrared (FTIR) spectra (transmission mode) of neat PP, PP/HNTs, PP/carvacrol and PP/(HNTs-carvacrol) films, presenting the 1800–700 cm⁻¹ region. Spectra of pristine HNTs and carvacrol are also included for comparison. The spectra of the PP/carvacrol and PP/(HNTs-carvacrol) films suggest homogeneous distribution of the carvacrol within the PP matrix. Peaks at 973 cm⁻¹ and 841 cm⁻¹ were used for estimation of the crystallinity in the PP films. Note that the spectrum of carvacrol is presented on a smaller absorbance scale, for clarity.