Rheological properties and viscoelastic response of PLA/PCL blends

Poly(lactic acid) (PLA) and poly(έ -caprolactone) were melt blended using an internal mixer. The morphology of PLA/PCL blends was observed by scanning electron microscopy (SEM). The linear rheological behavior of PLA/PCL blends were investigated at strain 1%. The results show the clear phase separation for immiscible PLA/PCL blend where PCL disperses evenly in PLA matrix that size of PCL particle increase with addition of PCL content. Linear viscoelastic behavior shows that Newtonian behavior at low frequency and shear thinning behavior with addition frequency value. With addition PCL to PLA matrix shear thinning behavior observed nearly, storage modulus, loss modulus increase. In the other hand, complex viscosity of PLA/PCL increase because PCL has higher viscosity rather than PLA.

Keywords:

polymer blends , rheology , poly (lactic) acid , poly(έ-caprolactone)