In the last two decades,
the use of phthalates has been restricted
worldwide due to their well-known toxicity. Nonetheless, phthalates
are still widely used for their versatility, high plasticization effect,
low cost, and lack of valuable alternatives. This study presents the
fully bio-based and versatile glycerol trilevulinate plasticizer (GT)
that was obtained by the valorization of glycerol and levulinic acid.
The mild-conditions and solvent-free esterification used to synthesize
GT was optimized by investigating the product by Fourier transform
infrared and NMR spectroscopy. An increasing content of GT, from 10
to 40 parts by weight per hundred parts of resin (phr), was tested
with poly(vinyl chloride), poly(3-hydroxybutyrate), poly(3-hydroxybutyrate-co-3-hydroxyvalerate), poly(lactic acid), and poly(caprolactone),
which typically present complicated
processability and/or mechanical properties. GT produced a significant
plasticization effect on both amorphous and semicrystalline polymers,
reducing their glass-transition temperature and stiffness, as observed
by differential scanning calorimetry measurements and tensile tests.
Remarkably, GT also decreased both the melting temperature and crystallinity
degree of semicrystalline polymers. Furthermore, GT underwent enzyme-mediated
hydrolysis to its initial constituents, envisioning a promising prospective
for environmental safety and upcycling. Furthermore, 50% inhibitory
concentration (IC50) tests, using mouse embryo fibroblasts,
proved that GT is an unharmful alternative plasticizer, which makes
it potentially applicable in the biomedical field.