Segmental Dynamics in Poly(ε-caprolactone)/Poly(L-lactide) Copolymer Networks

Poly(epsilon-caprolactone) (PCL) and poly(lactic acid) (PLA) networks were prepared from macromonomer diols runctionalized with methacrylic anhydride, which allows one to get self-crosslinkable polymers. Besides, both macromonomers were copolymerized to get copolymer networks with different compositions (namely, PCL/PLA: 0/100, 70/30, 50/50, 30/70, 100/0). Dielectric and calorimetric experiments allow one to conclude the microphase separation of the system: one phase made of pure PCL domains while the second one consists of caprolactone units, which somehow plasticize PLA and moves its main relaxation (glass transition) to lower temperatures. The effect of crosslinking PLA on the dynamics of the system was further investigated by comparing with the dynamics for linear PLA. (C) 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 183-193, 2009