A new polyester poly(glycerol butenedioate) (PGB) was
obtained
in the bulk polycondensation of glycerin and maleic anhydride. Glycerol
polyesters are new biomaterials commonly used in tissue engineering.
PGB, containing the α,β-unsaturated moiety, could be very
interesting due to potential modifications such as additions or oxidation.
Such modifications are not possible on the heretofore known glycerol
polyesters due to their structure without α,β-unsaturated
moieties. In this work, the developed process was optimized by applying
the design of experiments. The optimization criterium was the minimization
of the E/Z isomer ratio. Applying the two-stage process, the
E
/
Z
isomer ratio was reduced from 5.5 to
0.5 compared to the one-stage process. The degree of branching was
also reduced from 17 to 9%, as well as the degree of esterification
from 0.89 to 0.72. The obtained structure can be used in modifying
or cross-linking via Michael additions.