Effect of Low Loading Biodegradable Poly(Ethylene Carbonate) to Physicochemical and Mechanical Properties of Melt-Blended Poly(Lactic Acid)

Abstract

Poly(lactic acid)/poly(ethylene carbonate) (PLA/PEC) blends with a low ratio range of PEC contents were successfully prepared via the melt blending technique. The objectives of this study are to evaluate the effect of low content of PEC on the PLA and further characterize the blend using torque analysis, Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC) analysis, Fourier Transform Infra-Red (FTIR) analysis, and mechanical properties. The PLA/PEC samples with different ratios, which is PLA98/PEC2, PLA96/PEC4, PLA94/PEC6, PLA92/PEC8, and PLA90/PEC10, are selected in this research. The addition of PEC content in PLA reduced the torque value. The PLA90/PEC10 blends degraded first, and 5 wt% weight loss (Td5) of the PEC/PLA blends was decreased with PEC, which influences the thermal stability of the blends. The crystallinity of PLA has changed with the addition of 10% of PEC, resulting in the highest crystallinity up to 48.81%, thus influencing the toughness of the blends, giving the PLA a better modulus of toughness, and increasing the elongation at the break due to the plasticizing effect. Slight changes in the absorbance peaks of carbonyl and ether groups have confirmed the interaction between PLA and PEC even at a low loading of PEC. Due to the low loading of PEC content to PLA, the absorbance peak of PLA/PEC blends for the carbonyl group tends to shift towards a neat PLA peak. Thus, low PEC loading is strongly suggested as an alternative to PLA modification in various applications.