engleski

Kinetic analysis of poly(ε-caprolactone)/poly(lactic acid) blends with low-cost natural thermoplastic starch

Non-isothermal thermogravimetry in an inert atmosphere was used to investigate the thermal stability of poly(ε-caprolactone) (PCL), polylactide (PLA), thermoplastic starch (TPS) and their binary (PCL/PLA, PCL/TPS and PLA/TPS) and ternary (PCL/PLA/TPS) blends. All investigated blends were prepared by Brabender kneading chamber. A two-stage degradation pattern is seen in the case of PCL, while PLA exhibits only single stage degradation. On the other hand, the degradation of neat TPS proceeds through three degradation stages. It was found that addition of PLA affects the degradation of PCL/PLA blends indicating PLA’s destabilising effect on PCL. TPS addition thermally destabilizes both, PCL and PLA, but notably the PCL sample. Likewise, that addition of TPS thermally destabilized all investigated ternary blends. The obtained data were used for the kinetic analysis of the degradation process. By using the isoconversional Friedman method and the multivariate nonlinear regression method kinetic analysis was performed. Kinetic analysis revealed the complexity of the thermal degradation process for neat samples and all investigated blends. Kinetic parameters (activation energy, pre-exponential factor and kinetic model) for each degradation stage of neat samples and all investigated blends were calculated.

kinetic analysis ; poly(ε-caprolactone) ; polylactide ; thermogravimetric analysis ; thermoplastic starch

nije evidentirano