FTIR-ATR

FTIR-ATR of modified fabrics shows bands centered at 3400 cm<sup>−</sup><sup>1</sup> corresponding to the hydroxyl groups from HEMA; this band was not observed in the pristine PET-fabric spectrum. A very strong band among 1713–1722 cm<sup>−</sup><sup>1</sup> corresponding to asymmetric vibrations of carbonyl groups and others around 1240 and 1095 cm<sup>−</sup><sup>1</sup> corresponding to C-O vibrations from ether groups were observed (Figure 1).

**Figure 1.** FTIR-ATR spectra of (**a**) unmodified PET, (**b**) UV PET95:5:0.5 67% hydrogel, and (**c**) γ60 PET90:10:50 400% hydrogel.

The bands due to the double bond from methacrylate groups were not observed, confirming the polymerization of the monomers included in the synthesis process.
