Tailoring the biodegradability of polylactic acid (PLA) based films and ramie- PLA green composites by using selective additives

This study explores the effect of plasticisers (lotader AX8900, polyethylene glycol and triethyl citrate) on biodegradability of polylactic acid (PLA) and its composites with halloysite nanotubes and ramie fabric by soil burial method. Changes in surface morphology and mechanical properties were evaluated to quantify the degradation behaviour of all samples. The results showed that the relative loss in tensile strength of ramie-PLA composites was more than that of neat PLA or plasticised PLA films. Also, ramie-PLA composite, where ramie fabric was treated with diammonium orthophosphate, had degraded entirely after 60 days of soil burial. It was also confirmed by Fourier transform infrared spectroscopy that the chemical structures of neat PLA and plasticised PLA films changed after the soil burial test. The use of these additives not only reduces the brittleness of PLA but also accelerates the biodegradation rate of PLA. Thus, PLA, along with additives, can help in reduction of carbon footprint and other environmental issues customarily associated with petro based polymers. Therefore, the finding supports the notion of PLA usage as a viable alternative to fossil fuel-based materials.