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Renewable resources are playing a key role on the synthesis of biodegradable polyols. Moreover, the incorporation of covalently linked additives is increasing in importance in the polyurethane (PU) market. In this work, previously epoxidized grape seed oil and methyl oleate were transformed into phosphorylated biopolyols through an acid-catalyzed ring-opening hydrolysis in the presence of HPO. The formation of phosphate polyesters was confirmed by FT-IR and P-NMR. However, the synthesis of a high-quality PU rigid foam was not possible using exclusively these polyols attending to their low hydroxyl value. In that way, different rigid PU foams were prepared from the phosphorylated biopolyols and the commercial polyol Alcupol R4520. It was observed that phosphorylated biopolyols can be incorporated up to a 57 wt.% in the PU synthesis without significant structural changes with respect to the commercial foam. Finally, thermogravimetric and EDAX analyses revealed an improvement of thermal stability by the formation of a protective phosphorocarbonaceous char layer.

Slurries with low viscosity and polystyrene (PS) nanoparticles concentration up to 52 wt.% have been synthesized in one-step process with no waste generation, by suspension polymerization and optimizing the concentration of dispersants (sodium dodecylsulfate, SDS, and the cosurfactant, CS). The CS was manufactured in situ from tetraethyl orthosilicate (TEOS) and vinyltriethoxysilane (VTES). The incorporation of the CS on the PS polymer was confirmed by FT-IR, EDS and TGA; observing the functionalization of PS nanoparticles with SiOH. Morphology and particle size of the dispersed solid, together with viscosity and stability of the polystyrene slurries (PSSs) were analyzed, finding an abrupt reduction of the viscosity for PSSs by combining SDS and CS. Addition of SDS and CS (3.0 and 1.5 wt.%, respectively) allowed to produce PSSs with improved stability (ζ = -48.5 mV after one year), low viscosity (20.5 mPa•s at 25 ºC) and Newtonian behavior, containing up to 40.0 wt.% of single-spherical PS nanoparticles (< 100 nm).

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