Results and discussion
Synthesis and characterization of the PLA-NR-PLA triblock
copolymers
The 1H NMR spectrum of the “PLA-NR-PLA” triblock copolymer
is shown in Fig. 3. The main characteristic peaks of the PLA endblock
were noticeable at 1.2 ppm (H14),1.5 ppm (H11), 4.4 ppm (H13)
and 5.2 ppm (H12). Their peak assignments were described in the
earlier section (3.2 Synthesis of PLA prepolymer). The chemical
shift at 4.4 ppm confirmed that the PLA prepolymer was the endblock.