The enzymatic ring-opening polymerization of a 6-membered cyclic depsipepti
de, 3(S)-isopropylmorphsline-2,5-dione in the bulk, was investigated by usi
ng lipases as catalysts at 100 and 130 degrees C. Unchanged monomer was rec
overed in the absence of the enzyme or using an inactivated enzyme, indicat
ing that the present polymerization proceeds through enzymatic catalysis. P
oly(3-isopropylmorpholine-2,5-dione) has a carboxylic acid group at. one en
d and a hydroxy group at the other end.