Figure 3.

(A) ATR-FTIR spectra of polymer films obtained from Hx pomace (poly Hx pomace) at 150 °C in air at the indicated reaction time. (B) Solid-state NMR spectra of polymers obtained from Hx pomace (black) and Hx skin (orange). The regions ascribed to –COOH, –CH–OH, –CH–O–, –CH₂–OH, and –CH₂–O– of Hx monomers (blue) are also included. (C–E) Evolution of the water contact angle, glass transition temperature, and tensile parameters, respectively, with the reaction time of the synthesis of poly Hx pomace in air. Inset in C shows a typical drop on a surface of poly Hx pomace after 20 h of reaction. DSC (inset of D) and stress-strain (inset of E) curves correspond to polymers obtained after: (blue) 3 h, (green) 6 h, (orange) 10 h, and (red) 16 h reaction.