Investigation of structure and properties of biodegradable compositions of polylactide with ethyl cellulose and chitosan plasticized by poly(ethylene glycol)

Compositions of polylactide (PLA) with polysaccharides ethyl cellulose and chitosan are obtained at different initial ratios of components under conditions of shear deformation in a Brabender mixer. It has been shown that the addition of a given amount of low-molecular poly(ethylene glycol) (PEG) leads to an increase in the elongation of rigid polysaccharide-PLA compositions. The influence of molecular weight and amount of PEG on the thermal behavior of PLA is investigated by DSC method. The biodegradability of films prepared from the blends under investigation is estimated by weight loss after holding in soil and tests on the fungus resistance, and it is shown that the compositions have good biodegradability. The changes in the film morphology after holding in soil revealed by the SEM method additionally confirm that compositions are subjected to biodegradation.