UV degradation of poly(lactic acid) materials through copolymerisation with a sugar-derived cyclic xanthate.

The copolymerisation of L-Lactide with a cyclic xanthate monomer derived from tri- O -acetyl-D-glucal has been used to incorporate thionocarbonate and thioester linkages into a polyester backbone. The poly(lactide- co -xanthate) copolymers show enhanced UV-degradability compared to PLA, with 40% mass loss within 6 hours of UV exposure (365 nm) for only 3% of sulfur-containing linkages.