Lactide recovery from poly:lactic acid for economical recycling of waste

摘要

Recovery of lactide (I) from a polylactic acid (II) of high mol. wt. comprises (a) heating (II) at least to its m.pt. in the presence of a catalyst of gp. IA, IVA, IVB and/or gp. VA metal(s) or cpd(s). and (b) reducing the pressure to at most the vapour pressure of (I) at this temp. to distil and recover the (I) formed.