On pressure and temperature affected shear viscosity behaviour of Poly(Lactid) acid melt

Rheological properties of a poly(lactid) acid (PLA) as one of the most important bio-base sustainable polymer potentially applicable for medical applications had been studied. Shear flow behaviour of PLA melt was determined using capillary rheometer modified by backpressure device directly connected to the main rheological apparatus. The device employed increases pressure actuating on polymer melt stream in capillary reservoir through restricting valve resulting in an increase of melt viscosity. The temperature and pressure sensitivity coefficients were determined through the viscosity data fitting with the Carreau-Yasuda model. The study revealed that shear viscosity of tested PLA melt is strongly affected by temperature and pressure