Polyester

Degradation (telecommunications)

Computer science

Engineering

Composite material

Chemical engineering

Polymer

Telecommunications

Thermodynamics

Melt flow index

Rheology

Copolymer

Fourier transform infrared spectroscopy

Materials science

Polymer degradation

Extrusion

Differential scanning calorimetry

Physics

Shearing (physics)

Polymers

This article presents the effect of twin-screw extrusion processing parameters, including temperature and rotational speed of screws, on the structure and properties of four grades of polylactide (PLA). To evaluate the critical processing parameters for PLA and the possibilities for oxidative and thermomechanical degradation, Fourier-transform infrared spectroscopy (FT-IR), oscillatory rheological analysis, and differential scanning calorimetry (DSC) measurements were used. The influence of degradation induced by processing temperature and high shearing conditions on the quality of the biodegradable polyesters with different melt flow indexes (MFIs)was investigated by color analysis within the CIELab scale. The presented results indicate that considering the high-temperature processing of PLA, the high mass flow index and low viscosity of the polymer reduce its time of residence in the plastifying unit and therefore limit discoloration and reduction of molecular weight due to the degradation process during me...

Correlation between Processing Parameters and Degradation of Different Polylactide Grades during Twin-Screw Extrusion