This paper concerns on the use of epoxidized natural rubber (ENR) as toughening agent for polylactide
(PLA). ENR with epoxidation content of 20 mol% (ENR20) and 50 mol% (ENR50) were separately melt
blended with PLA using an internal mixer. DSC results suggested that PLA/ENR blends were amorphous
after melt blending while they were crystalline and revealed two melting peaks in the thermograms after
being annealed at 100 C. Mechanical tests showed that the introduction of ENR reduced the tensile modulus
and strength but enhanced the elongation and the impact strength of PLA. The impact strength of the
20 wt% ENR20/PLA and ENR50/PLA blends increased to 6-fold and 3-fold, respectively, compared to that
of pure PLA. This enhancement was due to a good interfacial adhesion between ENR and PLA. Both
ENR20/PLA and ENR50/PLA blends performed very strong shear thinning behavior, and the complex viscosity,
storage and loss modulus of the blends also increased after blending with ENR.