Diallyl tartrate as a multifunctional monomer for bio-polymer synthesis

This paper introduces the use of a diallyl dicarboxylate compound, diallyl tartrate, as a monomer in the synthesis of a biodegradable polymer. Although the allyl functional group is generally known for not being able to polymerize to high conversions, it was found in this study that by using photoinitiation instead of thermal initiation, a highly cross-linked polymer could be obtained from the polymerization of diallyl tartrate in a relatively short time. The details of the polymerization reaction were investigated in detail using differential photocalorimetry (DPC). The final thermoset obtained was shown to be completely amorphous and rigid, with a glass transition temperature of approx. 90 degrees C and a storage modulus of approx. 1 GPa at room temperature, via thermal analysis. It was also found to biodegrade in vitro via hydrolysis of its ester groups at a moderate rate, taking nearly 12 weeks to lose 50% of its mass. Both the photo-polymerized material and its water-soluble degradation products were further shown to be non-cytotoxic to fibroblast cells over at least 24 h of exposure. These results aim to initiate the use of this class of monomers in the synthesis of new polymers with tailored properties for biomaterial applications.