PLA films with improved flexibility properties by using maleinized cottonseed oil

This work assesses the potential of maleinized cottonseed oil - MCSO as plasticizer in poly(lactic acid) - PLA films with improved ductile behaviour. The effects of MCSO are compared with commercially available maleinized oil, i.e. maleinized linseed oil MLO in terms of mechanical, thermal and barrier properties, as well as morphology changes. Plasticized PLA formulations were obtained with a maleinized oil content in the 0-10 wt% range. Addition of both maleinized vegetable oils leads to a slight decrease in the glass transition temperature (T-g) of neat PLA from 63 degrees C to 60-61 degrees C. Nevertheless, MCSO provides better overall properties. Addition of 7.5 wt% MCSO increases the elongation at break by 292%. Regarding the barrier properties, both maleinized vegetable oils increase the oxygen transmission rate - OTR. Nevertheless, this increase is less pronounced in the case of MCSO thus indicating its higher efficiency compared to MLO. On the other hand, addition of both maleinized vegetable oils do not compromise the overall disintegration of the obtained PLA formulations, thus positioning these additives as environmentally friendly solutions to increase ductile properties in PLA-based films.