Abstract:
The research aimed to enhance the isothermal cold-crystallization kinetics and morphology of poly(lactic acid) (PLA) sheet by an incorporation of filler as nucleating agent and the chemical surface modification of filler by silane coupling agent. The effects of filler type, content and isothermal annealing temperature on morphology, thermal and mechanical properties of PLA sheet were investigated. Sheets of PLA composites were thermoformed using a thermoforming machine. The thermal analysis from differential scanning calorimetry (DSC) showed that cold crystallization temperature (Tcc) of the PLA composites was lower than that of neat PLA, suggesting that filler acted as nucleating agent accelerating the crystallization rate of PLA. Adding talc at 5 vol% provided the fastest isothermal crystallization rate of PLA at 100oC. It was also found that incorporation of talc and CaCO3 increased tensile strength and Young’s modulus of the PLA composites. Moreover, the PLA composites containing silane-treated talc at 5 vol% showed the improvement of filler dispersion, which increased the interfacial area and interaction between talc and PLA matrix.
In addition, the mechanical properties of treated filler/PLA composite film did not significantly change much upon film stretching.
