Degradation of nanoclay-filled polylactide composites

Nanoclay-filled polylactide (PLA 3051D) composite materials were tested in this study and their capacity for degradation was investigated. Activated and lyophilized smectite clay was used. The filler, its morphology, and grain size distribution were characterized by the use of transmission electron microscopy, scanning electron microscopy, and the dynamic light scattering technique. Samples of pure polylactide and polylactide filled with 3% wt., 5% wt., and 10% wt. of nanoclay in subsequent series were obtained by injection molding. The optimum amount of the filler in the nanocomposites was evalu-ated based on an assessment of mechanical properties as well as capacity to degrade. The 3% wt. mass fraction of nanofiller in the polylactide matrix was found to be the most effective in enhancement of both tensile strength (RM) and Young’s Modulus (E). It was also reported that polylactide nanocomposites filled with 3% wt. of smectite clay were characterized by the highest decrease in molecular mass of the matrix polymer after degradation tests (6 weeks incubation in water at 80°C). The observed decrease in degradation time and the overall changes distinguished in the nanocomposite structure suggest the poten-tial for application of the material in the packaging industry.