Valorisation of Salvia Hispanica L. (Chia) Oil into Air-Drying Alkyd Resins: Towards Solvent-Free Nanodispersion Formulations and Their Oxidative Miniemulsion Polymerisation.

The current work was developed focusing on the synthesis of new polymeric latexes through the in reactor oxidative polymerisation of chia oil alkyd resins using the miniemulsion process. These latexes have potential applications, primarily in coating applications. Initially, an oil length mixture was obtained from chia oil through saponification and acidification reactions. The resulting mixture was characterized by ¹H-NMR and ¹³C-NMR, confirming the presence of unsaturation and the characteristic functional groups associated with this compound. Phthalic anhydride and glycerol (esterification reaction) were used in the synthesis of alkyd resin. Alkyd resins were obtained by varying the oil length content in its composition: 30% wt% oil length alkyd resin is called short alkyd resin, 43% wt% oil length is medium resin and 64% wt% is the long alkyd resin. The ¹H NMR spectra of alkyd resins showed peaks indicative of the presence of groups coming from phthalic anhydride and glycerol, as well as unsaturations that varied in intensity according to the size of the resin (short, medium or long). The miniemulsions were obtained from alkyd resins demonstrating colloidal stability over 90 days and with stable miniemulsions the oxidative polymerisation of the alkyd resins was carried out in a high-pressure reactor with temperature and pressure control and in the presence of the radicalinitiator benzoyl peroxide (BPO) and oxygen. Based on ¹H-NMR analysis, polymers are formed through the oxidative polymerisation of alkyd resins from chia oil using the miniemulsion process. These polymers can be used as a paint base with a low solvent fraction or no solvent, depending on the application, and without using heavy metals-based catalysts. [ABSTRACT FROM AUTHOR]