Accelerated solvent extraction, chemical modification, and free-radical polymerization of canola (Brassica napus), carinata (Brassica carinata), and crambe (Crambe abyssinica) oils

Abstract

This study compares the chemical modification and polymerization behavior of canola, carinata, and crambe oils to evaluate their suitability as renewable building blocks for polymer synthesis. The vegetable oils were characterized in terms of fatty-acid composition and oxidative stability, and the data showed distinct profiles: canola with 0% erucic acid, carinata around 42.08%, and crambe reaching 56.25%, differences that end up influencing how each one responds during the modification steps. Epoxidation and acrylation were confirmed by 1H NMR, 13C NMR, and FTIR-ATR, mainly through the disappearance of the olefinic peaks and the appearance of oxirane- and acrylate-related signals (some of them quite clear, others less pronounced). After acrylation, the oils were subjected to solution polymerization, forming bulk crosslinked materials, whose properties reflected their original fatty-acid profiles: the canola-based polymer reached the highest glass transition temperature (Tg), 47.73 ◦C, followed by the carinata-based polymer (Tg = 41.86 ◦C), while the crambe-derived polymer, with lower functionality due to its high erucic acid content, showed a much lower Tg of 20.26 ◦C. Altogether, these differences highlight how variations in fatty-acid composition subtly shape the efficiency of functionalization and the architecture of the resulting networks. The polymers obtained here point to potential uses in renewable coatings, thermoset resins, and other applications that depend on bio-based crosslinked materials.