A straightforward strategy for the efficient synthesis of acrylate and phosphine oxide-containing vegetable oils and their crosslinked materials

Phosphorus-containing triglycerides were prepared from a new route that involves the singlet oxygen photo-oxygenation of high oleic sunflower oil and further reduction of the resulting hydroperoxide derivatives to a mixture of secondary allylic alcohols. These allylic alcohols in presence of chlorodiphenylphosphine give allylic phosphinites capable to undergo a [2,3]-sigmatropic rearrangement leading to tertiary phosphine oxides directly linked to triglyceride in a one-pot two-step reaction. The obtained phosphorus-containing triglycerides with different hydroxyl content were activated to polymerization by acrylation and these acrylate triglycerides were radically crosslinked in presence of different amounts of pentaerythritol tetra-acrylate. The thermal, dynamic-mechanical, and flame retardancy properties of the final materials were evaluated. Thermal and thermo-oxidative degradation was studied by gas chromatography/mass spectrometry, 31 P HR-MAS NMR spectroscopy, and scanning electron microscopy.