Phase separation of the quaternary system PLLA/PLA/dioxane/water was investigated.
Demixing temperatures of blends are close to PLLA in the same mixed solvent.
Calculated spinodals confirmed this peculiar phase behavior.
Above PLA cloud point, morphology of blend foams is similar to pure PLLA foams.
Below PLA cloud point, morphology of blend foams resulted highly inhomogeneous.