2.3.3. Microstructural Characterization

A field emission scanning electron microscope (FESEM) model Zeiss Ultra, from Oxford Instruments (Abingdon, UK) was used to obtain micrographs from the cryofractured surfaces of the rectangular samples. The acceleration voltage was set to 2 kV. Previously, the samples were coated with an ultrathin platinum layer in a vacuum using a coater, model MED020 (Leica, Leica Microsystems). Micrographs of PLA with GR have not been reported, since there is literature that shows the effect of gum rosin on the PLA matrix [48].
