Macrocyclic oligoesters and compositions comprising macrocyclic
oligoesters are prepared from intermediate molecular weight polyesters.
In one embodiment, a diol is contacted with a dicarboxylic acid or a
dicarboxylate in the presence of a catalyst to produce a composition
comprising a hydroxyalkyl-terminated polyester oligomer. The
hydroxyalkyl-terminated polyester oligomer is heated to produce a
composition comprising an intermediate molecular weight polyester which
preferably has a molecular weight between about 20,000 Daltons and about
70,000 Daltons. The intermediate molecular weight polyester is heated and
a solvent is added prior to or during the heating process to produce a
composition comprising a macrocyclic oligoester. An optional step is to
separate the macrocyclic oligoester from the composition comprising the
macrocyclic oligoester.